Tree Pollination Process: All Tree Types Pollination Charts (Fruit, Conifer, More)

Georgette Kilgore headshot, wearing 8 Billion Trees shirt with forest in the background.Written by Georgette Kilgore

Gardening | February 14, 2024

Man holding two seedlings wonders about tree pollination and if there is pollination charts for fruit trees, deciduous trees, conifers, and what types of pollinators for trees are needed.

Tree pollination is an essential natural process that enables trees to produce seeds, grow fruit, and propagate future generations.

While the specifics of tree pollination vary across species, fundamentally, pollination is the transfer of pollen from the male reproductive part of a tree to the female reproductive part of the tree. When pollination is successful, it leads to fertilization of the plant and the development of seeds.

In fruit-bearing trees, successful pollination results in the tree being able to bear fruit. Other trees produce cones or nut shells depending on the species.

This guide provides you with a comprehensive overview of the tree pollination processes for all major types of trees including fruit, nut, and conifer trees, and provides pollination charts for a number of seed bearing trees, and how they propitiate.

Not only does it explain the pollination method for different types of trees, including those that self pollinate, it also explains how nature used pollinators like insects, animals and climate to aid the act. Moreover, it explains how specific tree species pollinate and how to ensure that you have adequate pollination for your plants to thrive.

Whether you are a home grower with a couple of backyard trees or managing a full-scale orchard operation, successful pollination is the foundation for productive trees.

4 Ways How Trees Distribute Pollen for Pollination

Trees have evolved with different strategies to spread their pollen far and wide to maximize cross-pollination opportunities depending on habitat and structure.

Graphic showing the three ways how trees distribute pollen which include Wind pollination (Anemophily), Animal pollination (Zoophily), and Water pollination (Hydrophily).

Here are the different ways how trees distribute pollen.

Wind Pollination (Anemophily)

Many trees like oak, pine, cypress, and birch rely on the wind to blow their dry, powdery pollen through the air from catkin to catkin (wind pollination).2 Wind-pollinated trees produce huge amounts of lightweight pollen grains to ensure enough to reach female flowers.

To better expose their pollen to wind currents, wind-pollinated species have catkins that dangle openly from branches. Trees adapted to wind pollination often grow together in dense stands which increases the chances of pollen transfer.

Animal Pollination (Zoophily)

Most flowering trees depend on animal pollinators like birds, bats, bees, and other insects to carry their sticky pollen from flower to flower (animal pollination).2

They attract pollinators using showy flower colors, alluring scents, and nourishing nectar.

Close-up of a honeybee feeding on some white flowers.

(Image: Ralphs_Fotos29)

Specialized flower shapes precisely match pollinators’ size and form to ensure effective pollen transfer. For example, hummingbird flowers have a tapered tubular shape perfectly suited to hummingbird beaks and heads.

By rewarding specific pollinators, trees avoid directly competing with generalist pollinators. This mutualistic relationship benefits both the trees and their pollinators.

Water Pollination (Hydrophily)

Although uncommon among trees, water pollination occurs in some aquatic plants.15

The pollen floats on the water’s surface to reach female flowers. White mangroves exclude salt from their flowers to float their pollen along coastal waters.

Multiple Methods

Some trees make use of multiple pollination strategies to increase the chances of successful fertilization. For example, alders produce both insect-pollinated flowers and wind-pollinated catkins on the same plant.

Additionally, wild cherries have showy insect-pollinated flowers but shed excess pollen into the wind.

Sometimes, the natural pollination mechanisms above may be insufficient or undesirable. In such cases, you can choose to hand pollinate your trees to guarantee success and improve production in fruit trees.

Close-up of a pawpaw flower being pollinated using a brush via hand pollination.

(Image: LincolnSmith30)

Hand pollination, also known as mechanical pollination, is a technique that requires you to use a medium such as a soft brush to physically transfer pollen from the male part of a flower to the female part.

Dragon fruit plant is a good example of a plant that benefits from hand pollination to increase the success of pollination and production of larger-sized fruits.

What Is Pollination?

Pollination is the transfer of pollen from the male reproductive part of a tree to the female reproductive part of the same tree or a different tree of the same species.23

Once successful, this process enables fertilization and the subsequent production of seeds to propagate the next generation. For pollination to succeed, viable pollen must move between compatible trees of the same species.

The specifics of pollination vary across different types of trees and species.

In amentiferae or catkin-bearing trees like willow, walnut, and oak, pollen is produced by the male catkins or cones.

Catkins or aments are tiny flowers grouped together in a cone-like structure. The small grains produced by the catkins contain the male plant’s sperm cells.

Close up of a Willow-Catkin Tree Flowers.

(Image: 0-0-0-027)

When a pollen grain reaches the female cone or flower stigma, it germinates, sending a pollen tube down to the ovule. The sperm cells travel down this tube to fertilize the egg cells in the ovary.

A fertilized ovule develops into a seed containing an embryo that will grow into a new plant. In others like pine cones, the seeds simply mature inside the cones.

In flowering trees, pollination involves the transfer of pollen grains from the male anther of a flower to the female stigma of the same flower, on a different flower on the same tree, or on different flowers of the same species. In fruit trees like apples, once fertilization is successful, the ovary swells into a fruit enveloping the seeds.

Understanding basic flower anatomy helps you understand the pollination process better:

Flower Anatomy: Parts of a Flower Involved in Pollination

First of all, it is important to note that not all flowers and trees are built the same.

  • Dioecious

Translates to “two houses”. This is a category of plants that have separate male and female cultivars of plants.

  • Monoecious

Translates to “one house”. This is a category of plants that have male and female flowers on the same tree.

Consequently, you cannot expect pollination to happen the same way across these different types of trees. Some trees have just one type of reproductive part (male or female), others have both and some can even change.

Kinds of Fruit Flowers

There are two kinds of reproductive parts in fruit flowers, male and female. However, there are fruit-bearing trees and plants that have male-only, female-only, or perfect flowers (a flower that has both male and female reproductive parts).

Here is a breakdown of the kinds of fruit flowers.

Type of FlowerExample of Fruit Trees
Perfect flowers only (flowers that have both male and female reproductive parts)Apples, cherries, citrus, figs, mangoes, peaches, pears, plums
Separate female flowers and male flowers but are found on the same treeAvocados, pomegranates
Female flowers only on one treePapayas, kiwis, mulberries, grapes
Male flowers only on one treePapayas, kiwis

Most plants have perfect flowers. However, on occasions where your tree has only one type of flower, you will need both female and male plants in order to get fruit.

So, with that out of the way, perfect flowers contain both male and female reproductive parts.

The stamen is the male structure, consisting of the anther at the tip which produces pollen grains, and the filament which holds up the anther. The carpel is the female structure, containing the stigma, style, and ovary.

The sticky stigma is where pollen grains land and germinate.

The style is a tube that leads down to the ovary which contains the ovules that can be fertilized by pollen to become seeds. Once pollinated, the ovary swells into the fruit while the seeds develop inside.

Petals, sepals, and bracts (modified leaves) form the structure protecting the reproductive parts of the flower. Their bright colors, shapes, scents, and nectar attract pollinators to the flowers.

The layout of a flower’s reproductive parts promotes cross-pollination from other flowers.

Flower PartDescription
SepalsGreen, leaf-like structures comprising the calyx that encase and protect the flower bud.
PetalsOften brightly colored modified leaves forming the corolla to attract pollinators. Petals often have markings guiding pollinators to the nectar.
StamensCollective term for the male flower organ consisting of a pollen-producing anther atop a slender filament stem.
CarpelsCollective term for the female organ composed of; an ovary at the base containing ovules and which becomes the fruit/cone after fertilization; a style shaft which is a tube that allows pollen tubes to grow down to the ovules; and a pollen-receptive stigma tip which is a sticky surface that catches and traps pollen grains.
NectariesSpecialized glands that secrete sugary nectar to attract and reward insect pollinator visits.
BractsModified leaves subtending flowers that are sometimes colorful like petals.

Flowers also produce distinct scents to lure their preferred pollinators. Their shapes, colors, aromas, and bloom times all evolved to optimally attract and interact with specific animal pollen transporters.

Understanding how a fruit tree flower is constructed will help you recognize the pollination process in action. Proper pollen transfer relies on flower parts functioning appropriately and pollinators effectively delivering viable, compatible pollen when stigmas are receptive.

Two Types of Pollination

Another important thing to note is that pollination heavily depends on effective pollen dispersal. There are two main types of pollination:

1. Self-Pollination

Self-pollination occurs when pollen from a flower fertilizes the same flower (autogamy) or another flower on the same individual plant (geitonogamy).12 Some trees and fruit varieties are self-compatible, meaning their own pollen can successfully fertilize their flowers.

Although this process is fast and simple, it leads to a reduction in genetic diversity since the sperm and egg cells have the same genetic information.

Examples of fruit trees that self-pollinate include; peach, nectarine, sour cherry, apricot, and most citrus trees. These trees, among others, do not need another tree of the same species nearby to produce fruit.

However, even though they are “self-sufficient”, most self-pollinating trees benefit from cross-pollinating with another variety in order to increase fruit yield and quality.

2. Cross-Pollination

Also called outcrossing, cross-pollination happens when pollen is transferred from one tree to the stigma of a different individual tree or plant of the same species.12 It is important to note that not all plants of the same species are compatible for cross-pollination.

As such, the pollen must be compatible for fertilization to take place. Cross-pollination promotes genetic diversity, and adaptability and often increases fruit production compared to self-pollination.

Examples of fruit trees that require cross-pollination are apple, plum, sweet cherry, pear, and most nut trees. These trees need another compatible tree of the same or a related species nearby to produce fruit.

The success of fertilization depends on factors such as flowering time, pollen compatibility, and chromosome number.

Most tree species cannot self-pollinate effectively. Their flowers are self-incompatible, meaning pollen from the same flower or tree cannot fertilize the ovule.

As such, these trees rely on cross-pollination brought by external pollinator agents like insects, wind, or animals.

How Does Cross Pollination Help Fruit Set in Fruit Trees?

Cross-pollination between two genetically different trees of the same species improves fruit production in many fruit trees. This introduces greater genetic diversity, improving pollination success and fruit set.

In cross-pollination, pollen from one tree fertilizes flowers on a different tree. This contrasts with self-pollination where the same flower or tree pollinates itself.

Self-pollination can cause inbreeding depression where offspring are less vigorous. In contrast, cross-pollination mixes up genes between trees, producing healthier seeds and more bountiful fruit crops.

For a reliable fruit set, apple, pear, sweet cherry, plum, and other trees require compatible cross-pollination partners. Even self-fertile varieties produce better with a pollinizer variety interplanted every few trees.

Bees play a critical role in carrying diverse pollen between flowers of fruit trees. Other orchard pollinators include flies, beetles, butterflies, and birds like hummingbirds.

What Fruit Trees Are Self-Pollinating? (Self-Pollinating Fruit Trees or Self-Fertile Fruit Trees)

While cross-pollination improves fruiting in most tree species, some fruit varieties are self-fertile or self-pollinating.5 This means that their flowers can successfully pollinate themselves without pollen from another tree.

The following fruit trees tend to be self-pollinating and do not require a pollinator variety:

  • Peaches: Most common varieties are self-pollinating except J.H. Hale which needs a pollinator.
  • Apricots: Moongold, Sungold, Tilton, and other popular varieties are self-pollinating.
  • Sweet cherries: Lapins, Stella, and a few others are self-fruitful.
  • Tart cherries: All sour cherry varieties are self-pollinating.
  • Plums: Methley, Satsuma, and Santa Rosa plus some European types are self-fertile.
  • Nectarines: Self-fruitful except for Mericrest which needs a pollinator variety.
  • Figs: Produce seeded fruit from self-pollination by fig wasps.
  • Persimmons: Many Oriental persimmon cultivars are self-fertile.
  • Pomegranates: Pollinated by bees but usually self-pollinating.
  • Gooseberries: Invicta, Hinnonmaki, and most other varieties are self-fertile.

That said, it is important to note that even self-pollinating trees produce better with a pollinizer variety. However, they can still set adequate fruit without one.

If you are a home gardener with limited space, choosing self-fruitful trees might be more appropriate.

The Step-By-Step Pollination Process in Trees

Understanding the sequence of pollination helps you support this crucial activity.17 Here is a step-by-step look at how various trees accomplish pollen transfer from anthers to stigmas and subsequent fertilization:

Fruit Trees (Apples, Peaches, Cherries)

  1. At their blooming time, flower buds open to release fragrance, colors, and nectar that attract pollinating insects.
  2. Bees, beetles, flies, and other pollinators visit the open flowers to feed on nectar.
  3. As they move between flowers, pollen grains from the anthers stick to their bodies.
  4. This pollen is then deposited onto the sticky stigma of the next flower they visit.
  5. Once on the stigma, the pollen grain germinates and grows a tube down the style towards the ovules in the ovary.
  6. Sperm cells travel through the pollen tube to fertilize the ovule, forming a seed.
  7. Hormones from the developing seed trigger the growth of the surrounding ovary into a fleshy, nutritious fruit enveloping and protecting the seed.

Conifers (Pines, Firs, Cedars)

  1. Male cones shed clouds of lightweight, winged pollen grains into the wind.
  2. Wind currents and gravity carry grains that land directly on exposed female cone scales.
  3. Pollen enters the female cone through a small pore and accumulates in a pollen chamber around each ovule.
  4. The grain germinates, forming a pollen tube that reaches down to fertilize the ovule.
  5. Fertilized ovules mature into winged seeds held within the female cones.
  6. Mature cones open to release seeds or drop entire cones for seed dispersal.

Deciduous Trees (Oaks, Maples, Birches)

  1. Lengthening daylight signals catkins to swell and release pollen into the air.
  2. Male catkins may elongate and dangle freely to better catch wind currents.
  3. Light, dry, powdery pollen grains are whisked far and wide by gusts of wind.
  4. Some land on and stick to female flowers’ stigmas, which protrude to snag pollen.
  5. The pollen grain then forms a tube to send sperm to ovules, fertilizing them into seeds.
  6. Seeds mature protected by pods, husks, nuts, or samaras depending on species.
  7. Seeds drop or are spread by animals once mature to propagate new trees.

Observing the chain of events in tree pollination enables you to pinpoint potential issues and improve fruit yield and quality through timely orchard management practices.

Why Is Effective Pollination Important for Trees?

Successful pollination enables trees to produce seeds and propagate future generations of trees.22 Without pollen transfer between male and female flowers or cones, trees can’t reproduce sexually.

Inadequate pollination leads to low seed production and reduced forest regeneration. When trees fail to reproduce, whole populations are at risk of declining over time.

Pollination also improves the genetic fitness of tree species.

Pine Tree flowers releasing pollen into the wind.

(Image: W.carter28)

Cross-pollination between different individual trees increases genetic diversity and adaptability. It allows beneficial traits to spread through the gene pool.

For orchard trees and other fruit producers like apples, proper pollination is crucial for bountiful fruit harvests. With inadequate pollination, trees produce misshapen or underdeveloped fruit.

Supporting effective pollination results in healthier, more productive trees and diverse, resilient forests!

Timing of Pollination

Pollination can only occur during the period when a tree’s flowers or cones are receptive.13 Flowering or blooming time varies widely by tree species and variety.

Some tree flowers open earlier to take advantage of pollinating insects emerging in spring. Others bloom later to match populations of key pollinators, or when favorable weather brings the pollinators out.

Flower parts like stamens and carpels also mature and become receptive in stages. By carefully timing and observing flower anatomy, you can promote cross-pollination between different flowers more effectively.

Environmental Factors

Successful pollination also depends on having a suitable environment. Inclement weather when flowers are blooming can limit pollinator activity.

Pesticides can also reduce pollinator populations. Insufficient sunlight, water stress, air pollution, and poor soil nutrition also affect pollination success.

Orchard design, cultivation practices, and pollinator habitat management can help overcome environmental limitations to improve pollination rates.

Pollination Requirements of Common Tree Types

From mighty oaks to dainty Japanese maples, all the diverse trees require pollination. Here’s a look at how some of the most popular types disperse their pollen.

Deciduous Trees

Oaks, maples, ashes, birches, poplars, willows, hickories, elms, mulberries, and many other deciduous trees are wind-pollinated.

However, research shows that bees and other insects frequently gather their pollen, incidentally aiding pollen transfer.10

Some trees like tulip poplars and black locusts produce such heavy, sticky pollen that bees deliberately collect it. That said, insect pollination is still secondary to wind dispersal.

Oak Trees

Oak Tree flowers are unisexual with male and female flowers on the same plant.

Male oak flowers form yellow-green catkins that dangle downwards from twigs and branches. These catkins release massive amounts of powdery yellow pollen to float far and wide on the wind.

Close-up of young oak leaves and female flowers in the setting sun with the leaves dusted with pollen from the male flowers

(Image: W.carter31)

Meanwhile, female oak flowers cluster in small spikes with bright red stigmas to catch airborne pollen. Oaks depend entirely on wind for pollination.

Close-up of tiny, sphere-shaped Maple Tree flowers attached to their stem during spring.

(Image: pdcob1032)

Maple Trees

Depending on the species, Maple Trees have a male, female, or both sexes of small flowers clustered together on slim, drooping stems.

Red maples and silver maples have different male and female flower clusters on the same tree.

However, box elders bear only male or female flowers on separate trees.

Maples release copious amounts of dusty pollen that travel with the wind to pollinate. Varieties with red or yellow flower clusters also attract early spring pollinating insects.

Birch Trees

Slim male catkins and small female flower clusters both form on the same birch tree. The males release clouds of yellow pollen that the wind carries to fertilize female flowers.

In spring, you will notice that falling pollen often coats cars and other surfaces underneath birches.

Close-up female catkins from a silver birch tree showing two elongated cylindrical clusters of tiny flowers in an upright position.

(Image: Peter O’Connor33)

Some birch species also have colorful, scented flowers that attract pollinating insects. River birches produce starch-rich pollen that feeds beetles, flies, and other early-season pollinators.

Close-up of tiny white Cherry Tree flowers and buds attached to a stem during spring.

(Image: MolnarSzabolcsErdely34)

Cherry Trees

Wild cherry species like black cherry and pin cherry have fragrant white flowers pollinated primarily by insects. Honeybees, hoverflies, butterflies, and more feast on cherry blossom nectar and pick up pollen in the process.

That said, cherry trees also shed excess pollen to the wind.

Ornamental flowering cherries brighten parks and gardens every spring when they bloom. However, most of these trees don’t pollinate nearby fruiting cherry trees.

Walnut Trees

Walnut Tree flowers bloom before the leaves emerge.

Males have drooping catkins that release massive amounts of wind-borne pollen. Females have tiny flowers with bright red stigmas for catching pollen.

Close-up of a female flower from a walnut tree surrounded by green leaves.

(Image: Georg Slickers35)

Some walnut varieties only produce male or female flowers (dioecious), so planting both sexes ensures nut production. Squirrels help spread walnuts once pollinated flowers form nuts.

Coniferous Evergreens

Pines, spruces, firs, hemlocks, redwoods, cypress, and other conifers disperse dry, lightweight pollen on the wind to pollinate.19 Their male and female cones grow separately on the same tree.

Some conifer species rely partly on birds and insects to supplement wind pollination.

Pine Tree male flowers and needle-like leaves on a sunny day.

(Image: Eirena36)

Pine Trees

Pine cones contain both male and female flowers.

Male cones are small and shed tons of yellow pollen in spring. Female cones have sticky scales to snag airborne grains.

Each pollen grain fertilizes an ovule that matures into a winged pine seed.

Interestingly, pine pollen is sometimes too large for wind dispersal.

Instead, it drops directly onto female cones below or gets flicked onto them by rain, animals, or gravity. Strong wind can also knock free pollen from branches to fertilize nearby trees.

Fir Trees

Firs are monoecious with separate male and female flowers on each tree.

Female cones stand upright while males hang downwards on branches. The male catkins shed masses of pollen grains that are dispersed by wind currents.

Close-up of a young female cone from a Rocky Mountain Douglas-fir at the time of tree pollination.

(Image: Ivar Leidus37)

Fertilized female cones remain on the tree for a year before opening to release winged fir seeds. Douglas fir cones have fringed scales that catch pollen particles floating through the air.

Image of an Eastern Red Cedar Tree showing the cones shedding pollen into the wind as part of its pollination process.

(Image: Famartin38)

Cedar Trees

Female cedar cones are egg-shaped while males are small and shed yellow pollen. Cedars like junipers release tons of lightweight pollen for wind dispersal.

In early spring, people sniffle due to high cedar pollen counts.

The female cedar cones take over a year to mature after pollination.

When ready, their scales spread to release the tiny winged seeds. Deer and birds then distribute the seeds.

Cypress Trees

Male cypress cones are quite small, just 0.4 inches (1 cm) long. They produce massive amounts of pollen dispersed on the wind.

Females sport much larger cones up to 2 inches (5 cm) that protrude from branches. The cones consist of hard scales with a warty surface that catches airborne pollen grains.

Several clusters of Cypress Tree flowers attached to twigs and surrounded by leaves.

(Image: usiebertz39)

After pollination, female cones stay on the tree for nearly two years before shedding mature seeds.

Close-up of sphere-shaped European yew flowers of male plants that produce yellow pollen in spring, surrounded by long, thin leaves.

(Image: Didier Descouens40)

Yew Trees

European yews have separate male and female cones on the same tree.

The female cones mature in the fall about 6 months after pollination. However, the small, rounded male cones shed pollen the following spring.

Interestingly, yews stagger pollen and seed release. This likely discourages self-pollination between male and female cones on the same yew tree.

As such, the wind carries the pollen between neighboring yew trees.

Pollination of Popular Fruit Trees and Bushes

Successful fruit production hinges on effective pollination. While methods vary, most fruit trees and bushes require pollen transfer by insects or other external pollinators.

Understanding their specific pollination needs will help you maximize your fruit harvest.

Apple Tree Pollination

Apples depend on insect pollinators like honeybees to fertilize their pretty, lightly scented blossoms.7

Each flower contains both male and female parts (perfect flowers). However, most apple varieties are self-incompatible.

As such, pollen from a different compatible variety is required for fruiting.

What’s more, even self-fertile apple varieties like ‘Jonagold’ produce larger, higher quality harvests with cross-pollination. Crabapples frequently pollinate nearby apples thanks to their prolonged blooms.

Planting different apple varieties together ensures that you achieve adequate pollination. Hives of managed honeybees are essential for commercial orchards.

Apple Pollination Chart

Apple VarietyPollination GroupPollination TypeCompatible Pollinators
HoneycrispMid-seasonRequires cross-pollinationCortland, Empire, Gala, Granny Smith, Jonathan, Red Delicious
GalaEarly seasonRequires cross-pollinationFuji, Granny Smith, Honeycrisp, Jonathan, Red Delicious
Granny SmithLate seasonSelf-pollinatingNone needed
FujiLate seasonRequires cross-pollinationGala, Granny Smith, Honeycrisp, Jonathan, Red Delicious
Red DeliciousMid-seasonRequires cross-pollinationGala, Granny Smith, Honeycrisp, Jonathan, Rome
CortlandEarly seasonRequires cross-pollinationHoneycrisp, Empire, McIntosh, Red Delicious
JonathanMid-seasonRequires cross-pollinationGala, Granny Smith, Honeycrisp, Red Delicious
EmpireMid-seasonRequires cross-pollinationCortland, Honeycrisp, McIntosh, Red Delicious
McIntoshMid-seasonRequires cross-pollinationCortland, Empire, Honeycrisp, Red Delicious
Pink LadyLate seasonRequires cross-pollinationFuji, Granny Smith, Honeycrisp, Jonathan, Red Delicious
BraeburnLate seasonRequires cross-pollinationFuji, Granny Smith, Honeycrisp, Jonathan, Red Delicious
RomeLate seasonRequires cross-pollinationRed Delicious, Winesap
WinesapMid-seasonRequires cross-pollinationRome, Stayman, York
Golden DeliciousMid-seasonRequires cross-pollinationGranny Smith, Honeycrisp, Jonathan, Red Delicious
StaymanLate seasonRequires cross-pollinationWinesap, York
YorkLate seasonRequires cross-pollinationWinesap, Stayman
Pink PearlEarly seasonRequires cross-pollinationBraeburn, Granny Smith, Honeycrisp, Jonathan, Red Delicious
Arkansas BlackLate seasonRequires cross-pollinationFuji, Granny Smith, Honeycrisp, Jonathan, Red Delicious
LibertyMid-seasonRequires cross-pollinationRed Delicious, Rome
GravensteinEarly seasonRequires cross-pollinationHoneycrisp, Jonathan, McIntosh, Red Delicious
Northern SpyLate seasonRequires cross-pollinationFuji, Granny Smith, Honeycrisp, Jonathan, Red Delicious
Ashmead’s KernelMid-seasonRequires cross-pollinationHoneycrisp, Red Delicious, Roxbury Russet
Esopus SpitzenburgLate seasonRequires cross-pollinationHoneycrisp, Jonathan, Red Delicious
Roxbury RussetMid-seasonRequires cross-pollinationAshmead’s Kernel, Red Delicious, Rhode Island Greening
Rhode Island GreeningLate seasonRequires cross-pollinationRoxbury Russet, Stayman

Pear Tree Pollination

European and Asian pear varieties require cross-pollination from compatible partners. Like apples, most individual pear trees cannot self-pollinate.

Additionally, since pear flowers offer minimal nectar rewards, extra bee hives are needed to ensure pollination.

Compatible European and Asian pears will cross-pollinate but only when flowering simultaneously.9 Therefore, avoid planting unmatched varieties like ‘Seckel’ and ‘Bartlett’ together.

Pear Pollination Chart

Check pollination compatibility before selecting pear trees.

European Pears

Pear Fruiting VarietyCompatible Pollinizer
AnjouBartlett, Bosc, Comice, Anjou*, Seckel
BartlettAnjou, Bosc, Comice
BoscAnjou, Bartlett, Comice, Seckel
ComiceAnjou, Bartlett, Bosc, Seckel
SeckelBosc, Comice, Bartlett

Asian Pears

Asian Pear Fruiting VarietyCompatible Pollinizer
ChojuroShinseike, Bartlett
Nijisseiki (20th Century)Chojuro, Shinseike, Bartlett
HosuiPartially self-fruitful; any other pear in same bloom time OK.

Cherry Tree Pollination

Cherries may be self-fertile or self-sterile depending on variety. Note that sweet cherries and sour cherries will not cross-pollinate.24

For self-incompatible sweet cherries like ‘Bing’, make sure you plant compatible pollinator varieties like ‘Stella’ together.

Sour pie cherries are generally self-fertile and so pollinator trees are optional. Flowering ornamentals rarely pollinate nearby fruiting cherries. Also, make sure you protect cherries from rain to avoid cracked fruit.

Cherry Tree Pollination Chart

Pollen Compatibility Table

Fruiting varietyCompatible Pollinizers
BingSam, Van, Montmorency*, Rainier, Stella, Compact Stella, Garden Bing
LambertSam, Van, Montmorency, Rainier, Stella, Compact Stella, Garden Bing
RainierBing, Compact Stella, Garden Bing, Lambert, Montmorency, Royal Ann, Sam, Stella, Van
Royal AnnCompact Stella, Garden Bing, Montmorency, Rainier, Sam, Stella, Van
Stella, Compact Stella, Garden BingSelf-fruitful
VanCompact Stella, Bing, Garden Bing, Lambert, Montmorency, Rainier, Royal Ann, Sam, Stella
Montmorency (*tart/sour)Self-fruitful

Peach Tree Pollination Chart

With their pretty pink blossoms, peaches mostly pollinate themselves or other peach varieties. Exceptions like ‘J.H. Hale’ are self-sterile and hence require compatible peach pollinator trees.

Peaches bloom early before bees are very active so avoid applying pesticides during flowering. Minimal thinning is also needed for peaches.

Fruiting VarietyCompatible Pollinators
ElbertaJ.H. Hale, Hal-Berta
Hale HavenElberta, Redhaven
J.H. HaleElberta, Hal-Berta, Redhaven Redhaven Elberta, Hale Haven

Plum Tree Pollination

European, Japanese, and American plum varieties are largely self-incompatible and require a pollen source of another compatible plum variety.5

Avoid planting unrelated varieties like European with Japanese plums. ‘Methley’ and ‘Superior’ are the best options for resisting rain-induced cracking.

Plant at least two compatible Asian or European types together for cross-pollination. Alternatively, add ‘South Dakota’ or ‘Toka’ as universal pollinizers for other varieties.

Some ornamental and wild plum trees may also pollinate fruiting types.

Plum Pollination Chart

Belle de LouvainYes
Blue TitYes
Cambridge GagePartially
Coe’s Golden Drop *No
Denniston’s SuperbYes
Farleigh DamsonYes
Jefferson *No
King DamsonYes
Langley BullaceYes
Marjorie’s SeedlingPartially
Mirabelle Golden SpherePartially
Mirabelle RubyPartially
Old GreengageNo
Oullins Golden GagePartially
Reine Claude de BavayYes
Rivers Early ProlificPartially
Sanctus HubertusNo
Shropshire PruneYes
Warwickshire DrooperYes
Yellow PershoreYes

*Not suitable with Jefferson and vice versa

Blueberry Tree Pollination

With small, bell-shaped flowers, blueberries depend on bees for pollination and are self-fertile16 However, for bountiful blueberry harvests, plant more than one variety for cross-pollination.

Blueberry bushes flower very early in spring before most pollinators are active. Low chill types like ‘Sunshine Blue’ and ‘Misty’ and late flowering southern highbush varieties are more self-fruitful.

Northern highbush types produce larger yields with a compatible pollinator variety like ‘Bluejay’. Plant bushes within 6 to 8 feet (2 meters) of each other for easy pollination.

Blueberry flowers have small openings requiring sonicating bees that buzz-pollinate them.

Citrus Tree Pollination

Many seedless citrus fruits like navel oranges develop parthenocarpically without pollination.26 However, others require self- or cross-pollination for optimal fruit set.

Grapefruits, mandarins, and Clementines are often self-fruitful. Lemons, limes, and tangerines need cross-pollen transfer.

Citrus trees typically bloom in spring so flowering periods must align for cross-pollination.

Honeybees effectively pollinate citrus blossoms. However, if you need to gain the benefits of cross-pollination, plant compatible varieties within 60 feet (20 meters) of each other.

Grape Pollination

Grapes have small greenish flowers that bloom in clusters. Traditional table and wine grape varieties are self-pollinating and so pollinator plants are optional.6

Muscadine grapes, a common variety in the country with about 152 cultivars, need cross-pollination from a compatible muscadine variety planted within 50 feet (15 meters).

Wild grapes are dioecious with separate male and female vines.25 As such, make sure you cultivate both sexes near each other to produce fruit.

Grape flowers have a strong, sweet fragrance that attracts pollinators. However, wind and self-pollination are usually sufficient.

Stone Fruit Pollination

Apricots, peaches, nectarines, cherries, and plums are all stone fruits.4 Apricots are self-fruitful while peaches and nectarines mostly pollinate themselves.

Sweet cherries need cross-pollination but sour cherries do not. European and Japanese plums require compatible pollinators.

Make sure you space stone fruits appropriately for easy pollination and flower protection.

Fig Tree Pollination

All figs produce both male and female flowers on their unique internal fig fruit structure called syconium.14 However, fig wasps specifically adapted to fig flowers are the true fig pollinators.

The mutualistic wasp moves between “syconium” fruits transferring pollen.

In warm climates, fig trees grow well as solitary specimens since no external pollinator or partner tree is needed. However, in marginal climates, you need to plant two trees to boost fig wasp populations and pollination success.

There are also a few parthenocarpic fig varieties that develop seedless fruit without pollination at all.

Tropical Trees

The ornate, fragrant flowers of tropical trees are pollinated by diverse animals.

Bees service mango, lychee, longan, tamarind, and banana flowers.

Moths pollinate figs, and bats carry pollen between baobabs, kapok, and agave blossoms.

Hummingbirds favor hibiscus, poinciana, and African tulip tree flowers.

The flowering and pollination requirements for tropical and subtropical fruit trees also need careful consideration to support fruit production.

  • Mangos: Mangos (mangifera indica) contain both male and female flowers on each tree for self-pollination but also benefit from cross-pollination.20 Local insects typically provide sufficient pollination.
  • Papayas: Papaya trees are either male, female, or hermaphrodite.8 Female papayas need male trees interplanted for pollination.
  • Avocados: Separate male and female flower types mean avocados require cross-pollination.1 Mexican varieties typically pollinate West Indian types.
  • Passion Fruit: Mostly self-fruitful but fruit production improves with cross-pollination between two vines.3
  • Bananas: Banana flowers contain both male and female parts for self-pollination. Heavy pollen and hanging clusters aid wind dispersal.
  • Dragon Fruit: Night-blooming flowers pollinated by nocturnal creatures like moths and bats. They can self-pollinate but having two plants is recommended.
    You can also hand-pollinate to increase yield.
  • Lychee: They have separate male and female flowers on the same plant. Cross-pollination with other lychee trees, though supplemental, improves yields.
  • Longan: Self-pollinating flowers, but having a second longan tree boosts fruit set. Rain can reduce pollination.
  • Jackfruit: Monoecious species with male and female flower types on the same tree. Primarily wind and gravity pollinated.
  • Soursop: Self-pollinating but hand assistance improves fruiting. Time your flower visits based on changing sexes.
  • Sapodilla: Perfect flowers with male and female parts. Bees and other insects provide pollination.
  • Cacao: Cross-pollination is needed. Tiny midges and mosquitoes are their natural pollinators.
  • Fig: Unusual mutualistic relationship with tiny fig wasps. However, they will set small breba crops without pollination.
  • Persimmon: Dioecious species, needs both male and female trees present for pollination.
  • Pomegranate: Self-fruitful for pollination but benefits from cross-pollination.
  • Guava: Mainly self-pollinating but cross-pollination raises productivity.
  • Loquat: Flowers lack petals but contain reproductive parts. Sets fruit without pollination.
  • Breadfruit: Monoecious with male and female flower types. Insect pollinated.

Nut Trees

Most nut trees also rely on effective cross-pollination for good nut production.18

Common nut trees like pecans, walnuts, hickories, and chestnuts are primarily wind-pollinated. However, insect activity can supplement pollen transfer.

  • Pistachios

Pistachios have perfect flowers containing both male and female parts. But production improves with cross-pollination between clones..Hazelnuts perform best with two compatible varieties for pollen exchange.

  • Almonds

Most almond varieties are self-incompatible, requiring cross-pollination with a different variety for proper pollen transfer and fertilization. New self-fertile almond varieties have been developed that eliminate the need for a separate pollinizer tree.

Traditionally, commercial almond orchards relied on rented honey bee hives for pollination. However, other insects like mason bees also pollinate almonds effectively.

It’s important to match the bloom period of your selected varieties for overlap so pollination can occur.

  • Walnuts

Walnuts are wind-pollinated, not relying on insects for pollen transfer. The male catkins release large volumes of lightweight, dry pollen grains that are carried on the wind to female flowers on a different tree.

To ensure cross-pollination, it’s recommended to plant two compatible walnut varieties within a distance that enables wind pollination.

  • Chestnuts

Like walnuts, chestnuts also use wind pollination between male and female catkin flowers to pollinate. The male catkins emerge before the leaves fully develop to allow the pollen to disperse over greater distances without obstruction.

Planting two compatible chestnut varieties close enough for wind pollination enables cross-pollination for improved nut production.

  • Pecans

Pecans similarly rely on wind to carry pollen from catkins to tiny female flowers. The male and female flowers occur on separate catkin spikes.

For consistent cross-pollination, two compatible pecan varieties should be planted within the wind pollination range to exchange pollen.

  • Hazelnuts

Hazel catkin flowers also release pollen to be dispersed by wind. The pollen is carried between different hazelnut trees for cross-pollination.

To ensure adequate pollination, it’s advised to plant two compatible hazelnut varieties within typical wind pollination distance.

  • Pine Nuts

Conifers like pines use separate male and female pollen-bearing cones for reproduction.

As gymnosperms, conifers rely solely on wind for pollination, not needing insect pollinators. So, for pine, fir, spruce, and other conifers, cross-pollination occurs via wind without any required insect pollinators.

  • Coconut Palms

Coconut palms require cross-pollination between different trees for successful reproduction. Wind and insects like bees and beetles transport pollen between compatible varieties.

To ensure pollination, different coconut varieties should be interplanted, for example, combining ‘Malayan Tall’ and ‘Malayan Yellow Dwarf’ varieties to enable cross-pollination.

Common Tree Pollinators

Trees have coevolved with specific animal partners that fertilize their flowers in exchange for food rewards. Their coevolved relationships demonstrate the interconnectedness of nature.

Supporting pollinator-friendly habitats helps sustain productive and healthy trees.21 These important pollinators include insects, bats, birds, and more.


Bees are the most essential pollinators for the majority of flowering trees. Different bees have adaptations to pollinate diverse blossoms.

Bumblebees buzz-pollinate tomato and blueberry flowers by vibrating them to release pollen through small openings. Sweat bees, mason bees, mining bees, and many others contribute.

That said, the workhorse of agriculture is the European honeybee. Their furry bodies easily pick up and distribute pollen.

Honeybees pollinate fruit blossoms and provide beeswax, honey, and other products. However, native bees also deserve more recognition for their enormous ecological role as pollinators.

Butterflies and Moths

Butterflies favor flowers with clustered nectaries including dogwoods and buckeyes. Long-tongued moths like the yucca moth pollinate night-blooming flowers.

Declining butterfly and moth diversity directly threaten the plants that depend on them. Habitat loss and pesticides are also taking a toll on global pollinator populations.


While less nimble than bees, beetle pollinators are ancient. They feasted on early primitive flowers long before sophisticated bees evolved.

Beetles provide essential pollination for trees like Sweetbay magnolias. Their chewing mouthparts are ideal for consuming and transporting thick, protein-rich pollen.


Often overlooked, flies like hoverflies and bee flies are competent supplemental pollinators.

Mushroom-like carrion flowers trick blowflies into pollinating them. Flies have short rapid flights ideal for moving between flowers on the same plant.


Specialized tubular blooms lure hummingbirds with red or orange hues and ample dilute nectar. In reciprocation, hummingbirds transfer pollen between the flowers.

Favorite hummingbird trees include trumpet vines, red buckeyes, mimosas, and coral trees. Hummingbird numbers are declining so planting their preferred flowers provides essential food.


Bats follow scent trails to night-blooming flowers with musky or fermented odors, and brush pollen onto the next blossom they visit.

From southern magnolias to saguaro cacti, bats pollinate many trees that open after dark. It is important to protect bats and cave habitats since logging and development shrink their roosting and nesting areas.

Other Species

Some additional pollinators include birds, non-native honeybees, ants, wasps, squirrels, possums, lizards, and more.

Around 20,000 species globally spread pollen for over 87% of flowering plants. Preserving biodiversity and inter-connectivity sustains healthy, resilient ecosystems.

How To Attract Pollinators to Your Trees

Below are some simple steps you can take to recruit more pollinators to maximize fruit set and yield in your orchard while also supporting essential species in nature.

Plant Pollinator-Friendly Flowers

Provide nectar and pollen to nourish pollinators through the seasons.

Feature early blooms like willows and wild plums to feed emerging bees. Include night-scented flowers for moths like evening primroses and four o’ clocks.

For winter, provide late blooms like asters and goldenrods so insects can stock provisions in their nests.

Avoid Pesticides

Insecticides and fungicides harm bees, butterflies, beetles, and other beneficial species.

Use organic approaches to control pests only when absolutely needed. Always follow label precautions and avoid applying chemicals during blossom time.

Offer Clean Water

Give insects and hummingbirds fresh water for drinking and bathing. Make sure to change water frequently to keep it clean.

Add rocks, sticks, gravel, or marbles for safe perching and wading access.

Install a mister for butterflies on hot days. You can also consider adding a small backyard pond.

Provide Shelter

Insects need protection from weather and predators as well as nesting sites. Leave dead snags and leaf litter, and pile up branches and rocks to give pollinators a place to stay.

Image of a pollinator garden filled with purple prairie clover, purple coneflower, yellow coneflower and more that help attract pollinators to your trees.

(Image: USFWS Midwest Region41)

Hang old reeds and bamboo bundles for solitary native bees. You can also build houses for bats and birds.

Let Areas Go Wild

Embrace a more naturalistic look with sections of untended flowering plants, grasses, vines, and shrubs. Allow leaf litter to remain under trees.

These areas will provide food, shelter, and egg-laying sites.

Choose Native Plants

Native plants like milkweeds, asters, and sunflowers nourish local pollinators. They are adapted to regional conditions and suited to native pollinator needs.

Additionally, make sure to avoid invasive exotics that can overtake native species.

Link Habitats

Connect wooded areas, meadows, and water sources with hedgerows, bramble corridors, and stone walls. These links allow pollinators to safely travel from one habitat patch to the next.

Support Conservation Groups

Get involved in organizations like Pollinator Partnership, Xerces Society, National Wildlife Federation, and master gardener groups and programs.11 You can also advocate for local parks and public lands to adopt pollinator-friendly land management.

Tree Pollination Problems and Solutions

Despite their adaptations, trees still face challenges that hamper pollination.

Issues range from climate change to habitat loss. However, solutions exist to support tree propagation and evolution through effective pollination.

Climate Change

Warming weather alters flowering times which means trees flower before or after pollinating partners emerge. Migrating seasons also displace native pollinators.

Supporting interconnected habitats will aid the migration of pollinators to new areas. Additionally, providing supplemental food and shelter will boost their resilience.

Habitat Loss

Development divides and shrinks natural habitats needed for mating, nesting, feeding, and migrating.

Fragmented forests also reduce gene flow between tree populations. As such, it is important to protect existing natural areas and recreate habitat connections.


Chemical use eliminates pollinating insects and the plants they rely on. Broad systemic insecticides are especially harmful.

To deal with this, it is important to adopt pest prevention first, then use least toxic methods like horticultural oils or insecticidal soaps. Also, avoid spraying pollinators.

Invasive Species

Introduced weeds and exotic insects compete with and displace native pollinators, plants, and habitats.

You can take part in combatting this by regularly removing invasive plants. However, don’t move firewood which spreads tree pests.

Additionally, report invasive insect sightings to agricultural authorities.

Pollinator Declines

Dwindling bee populations threaten agriculture, ecosystems, food supplies, and economies. The specific causes are complex but include diseases, parasites, habitat loss, climate impacts, and pesticide overuse.

To address this, it is important to plant pollinator gardens on unused land in cities, suburbs, along roadsides, and farms. Also, avoid extracting honey from struggling wild hives.

Light Pollution

Artificial night lighting distracts nocturnal pollinators from their natural rhythm. It also disrupts flowering cycles keyed to moon phases and seasons.

To avoid light pollution, use motion-based, shielded, and wavelength-specific lighting. Also, turn off unnecessary lights.

Genetic Bottlenecks

Limited pollination causes inbreeding which reduces genetic resilience.

Additionally, fragmented habitats isolate plant populations. As such, it is important to promote connectivity through conservation corridors that enable gene flow between isolated groups.

Additionally, favor diverse wild species over clones.

Insufficient Pollination

With sparse pollinators, too few pollen grains reach plant stigmas. You can support pollinator health and habitat as a solution.

Hand-pollinate limited flowers by transferring viable pollen with small brushes. You can also mist flowers to dislodge pollen, introduce managed beehives temporarily, or plant alternate varieties that bloom at different times.

Hand Pollinating Trees

For treasured specimen trees, pollinators may be scarce.

To make sure that pollination still happens, you can pollinate fruit trees and ornamental plants yourself with a soft brush. Here’s how:

  1. Collect fresh pollen from dehiscing anthers on a male flower or catkin using a small paintbrush, cotton swab, or your fingertip.
  2. Transfer the pollen by dabbing and swirling it onto the stigma of a female flower. Repeat across multiple flowers to ensure adequate pollen.
  3. Visit flowers daily during peak bloom since stigmas are only receptive briefly. Label pollinated flowers with ribbon or tape.
  4. For dioecious trees, collect pollen from a male specimen and transfer it to a nearby female.

While this might be labor intensive for large orchards, hand pollination may be worthwhile for a prized tree variety or low-pollen heirloom variety grafted onto your property. By doing this, you become the tree’s reproductive matchmaker!

Successful pollination enables trees to produce the fruits, nuts, and seeds that sustain natural ecosystems and human communities. While techniques vary by species, pollen must transfer from male to female parts either within flowers or across different flowers.

Bees, wind, gravity, animals, or water can transport pollen. Many fruit trees need compatible partners for cross-pollination and good fruit production.

Use pollination charts to select productive combinations.

Unfortunately, many pollinator species now face an uncertain future.

Habitat loss, pesticides, invasive species, and climate change threaten these essential partners. Supporting pollinators through gardening, policy advocacy, and donations provides hope.

By understanding the pollination needs of key trees and making space for pollinators, you can play a vital role in sustaining future generations of people and trees. Your actions in orchards, woodlands, and backyards, however minor, make a big difference on the grand scale.

With care and compassion for pollinators, tree pollination can be enhanced, and you’ll reap the benefits of enhanced vegetation.

Frequently Asked Questions About Tree Pollination

Which Fruit Trees Are Self-Pollinating?

Many fruit varieties can self-pollinate (are self-fertile) including peaches, apricots, sour cherries, brambles, currants, gooseberries, grapes, and some plums, especially European types. But even self-fertile fruits generally yield more with a compatible pollinator variety.

How Do Pine Trees Pollinate?

Pines are primarily pollinated by wind with male pine cones shedding massive amounts of lightweight yellow pollen designed to float on air currents. The pollen then sifts down directly onto female cones (each pollen grain fertilizes one ovule nestled inside) or may travel slightly farther if propelled by animals, rain, or wind gusts.

How Do I Attract Pollinators To Improve Apple Tree Pollination?

You can draw more pollinators to your orchard by planting pollinator-friendly companion flowers nearby. Provide food plants from early spring through fall.

Can I Hand-Pollinate My Fruit Trees?

Yes, you can hand pollinate fruit trees by manually transferring pollen between flowers using a small brush, cotton swab, or even your fingertip. Collect fresh pollen from dehiscing anthers, deposit it onto receptive stigmas of open blossoms, and repeat across multiple flowers to maximize chances of pollen contacting stigmas during their brief fertile period.

How Close Should I Plant Pollinator Trees?

For reliable cross-pollination, pollenizer trees should be within these maximum distances: Apple – 50 feet, Blueberry – 6 feet, Cherry – 20 feet, Citrus – 60 feet, Peach/Plum – 100 feet, and Pear – 100 feet. Consider airflow patterns so the scent can travel between trees. For potted indoor trees, place compatible plants right next to each other or hand pollinate.


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27Photo by 0-0-0-0. Pixabay. Retrieved from <>

28Pine releasing pollen into the wind in Tuntorp Photo by W.carter / Attribution-ShareAlike 4.0 International (CC BY-SA 4.0). Cropped, Resized and Changed Format. From Wikimedia Commons <>

29Photo by Ralphs_Fotos. Pixabay. Retrieved from <>

30Pawpaw brush pollination Photo by LincolnSmith / Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0). Cropped, Resized and Changed Format. From Wikimedia Commons <>

31New oak leaves with female flowers Photo by W.carter / CC0 1.0 Universal (CC0 1.0) Public Domain Dedication. Cropped, Resized and Changed Format. From Wikimedia Commons <>

32Photo by pdcob10. Pixabay. Retrieved from <>

33Silver birch (Betula pendula) female catkin Photo by Peter O’Connor / Attribution-ShareAlike 2.0 Generic (CC BY-SA 2.0). Cropped, Resized and Changed Format. From Wikimedia Commons <>

34Photo by MolnarSzabolcsErdely. Pixabay. Retrieved from <>

35Juglans flower female Photo by Georg Slickers / Attribution-ShareAlike 2.0 Generic (CC BY-SA 2.0). Cropped, Resized and Changed Format. From Wikimedia Commons <>

36Photo by Eirena. Pixabay. Retrieved from <>

37Young female cone (length 3 cm) of the Rocky Mountain Douglas-fir at the time of pollination Photo by Ivar Leidus / Attribution-ShareAlike 4.0 International (CC BY-SA 4.0). Cropped, Resized and Changed Format. From Wikimedia Commons <>

38Eastern Red Cedar pollen cones shedding pollen Photo by Famartin / Attribution-ShareAlike 4.0 International (CC BY-SA 4.0). Cropped, Resized and Changed Format. From Wikimedia Commons <,_Mercer_County,_New_Jersey.jpg>

39Photo by usiebertz. Pixabay. Retrieved from <>

40European yew flowers of male plants Photo by Didier Descouens / Attribution-ShareAlike 4.0 International (CC BY-SA 4.0). Cropped, Resized and Changed Format. From Wikimedia Commons <>

41Pollinator Garden Photo by USFWS Midwest Region / Public Domain. Cropped, Resized and Changed Format. From Flickr <>