Silk Floss Tree: Identification Chart, How To Grow, ID Silk Floss Flowers (Pink)

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

Forestry, Trees and Tree Planting | March 28, 2024

Woman looks at silk floss tree (ceiba tree) and wonders how to grow silk tree (trees with thorns), and identify pink silk floss tree leaves, flowers, seeds, growing zones and planting tips.

With its large canopy, showy blossoms, and peculiar tufts of silk after pollination, the silk floss tree is a striking centerpiece for any landscape.

This tree, in fact, makes a great and lovely addition to many areas, and knowing how to properly care for it, plant it and grow one, can be a rewarding experience.

This guide provides information about the Silk Floss tree, including how to identify it, how to grow it, and how to ensure your pink Silk Floss flowers look their best each year.

Growing a Silk Floss Tree From a Seed, Cutting, or Seedling

If you want to grow a tree, take into consideration its location first. These trees have large root systems, with many of the roots forming large clusters near the soil surface.

The tree is also large, with sprawling and heavy branches. You will have to plant the tree at least 15 feet away from dwellings and roadways.2

Consider planting tips for silk floss trees, such as using soil amendments of an 80/20 mixture of potting soil with equal parts worm castings and perlite. Avoid planting the tree too deep within the soil.

The top of the root ball should be level with the grade of your soil. Growing a floss tree from a seedling is easy to do in a container with plenty of drainage holes.

Fill the pot with a mixture of amended soil and sand. Transfer the seedling to the container, planting the seedling deep enough only to cover the roots.

Place the container in a warm area, where it will be exposed to plenty of sunlight. Check the moisture level in the container, you want to keep the soil moist but not soaked.

After a few months, when the tree has begun to form stronger roots, but before it has become root-bound, transfer the tree to its final location. While growing a silk floss tree from a cutting is possible, it takes a bit more effort.

Clip off a young branch from the tree and remove its bottom leaves and stems. Dip the cut end into a rooting hormone and place the cutting either in water or in a mixture of amended potting soil and sand.

Some prefer water so they can monitor root growth. If you use water, top off the water weekly; if you use soil, keep the soil moist but not wet.

After a few months, you can transplant the cutting directly to its final location. Be careful when watering a tree, to avoid drowning the roots.

Trees can suffer from root rot the same as standard houseplants.

Best Growing Conditions for Silk Floss Tree (Silk Floss Tree Growth Rate)

Ideally, these trees need to be grown in warmer climates. They do not do well in colder climates and will suffer damage if exposed to temperatures below 27 degrees for a long time.

Graphics with texts and images that shows the best growing conditions for silk floss tree.

Consider how much sunlight does silk floss tree needs each day when selecting your location. They require at least six to eight hours of direct sunlight.

They will still grow in partial shade but bloom best when they receive direct sunlight. They need to be planted in well-draining, but moist soil.

Watering needs for silk floss trees are more frequent in the first year, several gallons three times a week to help establish the root system, but afterward, you can let the soil dry out between watering. Mulching around the tree conserves moisture.

The Ceiba Speciosa are drought-tolerant trees but will benefit from deep monthly watering during the summer season.

Pink Silk Floss Tree

(Ceiba Speciosa)

Photo of Silk Floss Tree in an oval frame on green background.
  • Characteristics: Large, blooming tree with a broad canopy and a green/grayish trunk covered with conical spikes. Fertilized seed pods release a cotton-like fiber.
  • Family: Malvaceae
  • Genus: Ceiba (previously called Chorisia)
  • Leaf: Palmate leaves with five to seven leaflets.
  • Bark: Thin bark green on young trees but gray as it matures.
  • Seed: Seeds are encased in large, heavy pods and wrapped in a moist silk-like fiber.
  • Blossom: Blossoms are pink with a yellow or cream center
  • Fruit: Large, heavy pods that contain small, oval black seeds
  • Native Habitat: South America: Argentina, Bolivia, Paraguay and Uruguay
  • Height: 40 - 60 feet
  • Canopy: Dense, averaging 30 feet in diameter
  • Type: Deciduous
  • Native Growing Zone: 9b - 11

IUCN Red List of Threatened Species Ranking

Least Concern

NE
DD
LC
NT
VU
EN
CR
EW
EX

Image Credit: David J. Stang8

What Is a Ceiba Tree or Silk Tree?

The Ceiba Tree is native to South America.8 It is large, reaching 60 feet tall, with a branch reach of roughly 20 to 30 feet around.

Its most defining characteristics are it being a spiky tree and its pink blooms, that later drop off to leave seeds. These seeds contain a silk-like material that erupts after fertilization, leaving puffy tufts that stand out brilliantly against its bare branches.

It is most widely used in decorative landscaping in warmer regions across the world.

Why Is the Pink Silk Floss Tree Also Called Ceiba Speciosa or Palo Borracho?

Its scientific name is Ceiba speciosa and according to the National Arboretum Canberra, the name comes from a combination of terms: Ceiba, the indigenous term for “large tree”, and Speciosa: Latin for “beautiful”.7

It was previously called Chorisia Speciosa because it had once belonged to the Chorisia genus, named after Ludwig Choris.1

Graphics with texts and images that shows how to identify silk floss tree through leaves, flower, seeds, and fruits.

(Leaves Image: Photo by David J. Stang9)

After reclassification, the tree was called Ceiba because that particular genus had been identified for a longer period. It is also called Pallo Borracho, which is Spanish for ‘drunken stick’.

Natives in Argentina used the water-resistant bark of the tree to carve bowls for fermenting alcohol.

Identifying Silk Floss Trees (How To Identify Silk Floss Tree)

There’s no mistaking the silk tree. It has a round, swollen trunk, studded with inch-long conical thorns, called prickles. It is one of the trees with thorns.

Branches grow horizontally from the trunk and are also covered in prickles.

Identifying Silk Floss Leaves

The leaves of this species are palmate, meaning that all of the leaf parts have a center rib that originates from the same spot on the stem.9 They are usually five to six inches wide and have five or seven lobes or leaflets.

Being dark green in color and dense, the leaves make the tree an ideal candidate for shade gardens.

Identifying Silk Floss Flowers

Ceiba Speciosa is a member of the hibiscus family, and therefore the fragrant flowers resemble that of a hibiscus bloom. The palm-sized blooms are pink at the edges of the petals and fade to a white or creamy center.

They have one central stamen. The tree sheds its leaves in the fall, after which the flowers bloom in clusters during the winter months, covering the bare branches in a showy display.

The flowers are also how tree pollination occurs. Hummingbirds or bees are attracted to the nectar in the bloom.

They pick up pollen from the anthers, or the male part of the flower, and deposit it onto the stamen, or female part. The blooms will fall off, leaving behind a fertilized seed pod, which then opens, exposing the kapok fibers inside.

The kapok is then shaken loose via gusts of winds or small animals, where it will fall to a nearby location.

Identifying Silk Floss Seeds

Silk floss seeds are held within heavy, wooden-like pods, usually around eight inches in length. The green pods eventually dry out, turning brown.

Inside they are filled with a white silk-like material, often called kapok, that envelops the black oblong seeds. The tufted material falls away from the tree via wind gusts or animal interaction and carries the seeds to a nearby location.

Companion Plants for Growing Silk Floss Tree

When considering companion plants for your tree, you want to look at varieties that can tolerate dry soil and the semi-shade cast from the wide canopy. Species like dwarf oleander and muhly grass are great options.3

If you want to have multiple trees, you need to consider how far apart to plant the trees, they need ample room to accommodate their massive girth and height. Plant each tree roughly 20 to 30 feet apart.

Silk Floss Tree Growing Zone and Rate

The growing zones for silk floss tree, where to grow them with optimal results, are in warmer regions of the country. In South America, they grow in zones 9b to 11, but in the United States, they will grow best in zones nine and 10.4

Worm's eye view of a Ceiba Tree or Kapok Tree showing its trunk and branches.

(Image: LoggaWiggler10)

You’re looking for planting zones that are generally warm and dry all year, with minimal cold temperatures as these trees will shed their leaves and experience stunted growth if exposed to prolonged cooler temps. The southern parts of California and Florida are excellent locations to cultivate these trees.

How long it takes to grow silk floss tree is short. They grow exceptionally fast during their first years, averaging 3 feet tall the first year.

After three years, the tree can reach almost 15 feet. Since the trees shed their leaves during the fall, young trees have a green tint to their bark that aids in photosynthesis.

As they mature, and the tree becomes more stable, the bark turns gray. They typically will flower after eight or 10 years.

Pruning is an important process to make sure the tree grows tall and sturdy. Make sure there is only one center stalk growing upward from the trunk and prune all side branches to maintain a diameter at least half of the size of the trunk to avoid splitting.

Generally, low-hanging branches can be pruned away for safety and will not regrow.

Silk Floss Tree Disease Prevention

The most common pests of the silk floss tree or floss silk tree are scale insects. These crawling insects latch onto the softer tissues of the leaves and stem and suck the sap from the tree.

They also secrete a substance that dries into black tar on the leaves, which prevents photosynthesis from occurring. An option for natural pest control for the silk floss tree is to utilize natural predators like parasitic wasps, that lay eggs on the scale.

Although, there aren’t many major concerns, knowing how to stop silk floss tree disease is helpful. The easiest method, especially for larger trees, is to prune away infected areas.

You may consider using chemicals like insecticidal soaps on smaller specimens.

A truly remarkable specimen, the Silk Floss tree is both exotic and beautiful, adding to your landscape just a touch of the intrigue and mystery synonymous with South America.

Frequently Asked Questions About Silk Floss Tree

What Are the Prickles, or Thorns, For?

The spikes of the tree were originally developed to deter climbing animals, such as monkeys and other small animals, that would eat the tree’s flowers and fruits, but now are more of a nuisance to cultivators, who have to be mindful of where they choose to plant them.

How Long Does It Take for a Tree To Grow?

These trees are fast-growing, gaining an estimated three feet per year.5 Some trees have been reported to be about 90 years old and measure 80 or 90 feet tall.

Does the Silk Tree Have Any Uses?

The kapok from the seed pods is water-resistant and was used as a filler material for life jackets.6 Seeds are compressed to secrete an oil similar to vegetable oil for cooking, additionally, the native inhabitants of South America have used the thin bark for braiding rope and the wood to carve boats and wood pulp, which then is used for paper making.

When To Plant Silk Floss Tree for the Best Yield?

Spring is the best time to plant your tree. This allows the tree ample time to acclimate to its new environment and build a strong root system.

Are There Any Other Considerations To Maintaining a Tree Like This?

The tree tends to drop its leaves in the fall, then the flowers in the winter, and finally the kapok fibers in spring. It is a continual cleanup process and if there are nearby gutters or drains, it makes for a time-consuming maintenance plan.

Read More About Silk Floss Tree

References

1San Marcos Growers. (2023). Ceiba speciosa. San Marcos Growers. Retrieved December 14, 2023, from <https://www.smgrowers.com/products/plants/plantdisplay.asp?plant_id=401>

2Fast Growing Trees. (2023). Pink Silk Floss Tree. Fast Growing Trees. Retrieved December 14, 2023, from <https://www.fast-growing-trees.com/products/pink-silk-floss-tree?variant=30245833113652>

3South Florida Plant Guide. (2023). Floss Silk Tree. South-Florida-Plant-Guide.com. Retrieved December 14, 2023, from <https://www.south-florida-plant-guide.com/floss-silk-tree.html>

4Gilman, E. F., Watson, D. G., Klein, R. W., Koeser, A. K., Hilbert, D. R., & McLean, D. C. (2019, April 11). CHORISIA SPECIOSA: SILK-FLOSS TREE. University of Florida. Retrieved December 14, 2023, from <https://edis.ifas.ufl.edu/publication/ST164>

5San Diego Zoo Wildlife Alliance. (2023). Floss Silk Tree. San Diego Zoo. Retrieved December 14, 2023, from <https://animals.sandiegozoo.org/plants/floss-silk-tree>

6Lee, B. (2017). SILK FLOSS TREE. University of Redlands. Retrieved December 14, 2023, from <https://sites.redlands.edu/trees/species-accounts/silk-floss-tree/>

7United States Department of Agriculture. (2023). Chorisia speciosa A. St.-Hil. United States Department of Agriculture. Retrieved December 14, 2023, from <https://plants.usda.gov/home/plantProfile?symbol=CHSP13>

8Ceiba speciosa 9zz Photo by David J. Stang / CC BY-SA 4.0 DEED | Attribution-ShareAlike 4.0 International. Cropped and added text, shape, and background elements. Wikimedia Commons. Retrieved December 14, 2023, from <https://commons.wikimedia.org/wiki/File:Ceiba_speciosa_9zz.jpg>

9Ceiba speciosa 8zz Photo by David J. Stang / CC BY-SA 4.0 DEED | Attribution-ShareAlike 4.0 International. Cropped and Added text, shape, background, and other image elements. Wikimedia Commons. Retrieved December 14, 2023, from <https://commons.wikimedia.org/wiki/File:Ceiba_speciosa_8zz.jpg>

10Photo by LoggaWiggler. Pixabay. Retrieved January 12, 2024, from <https://pixabay.com/photos/kapok-tree-ceiba-pentandra-pochote-323530/>