Rose Acacia, Bristly Locust, Moss Locust

Robinia hispida

Family: Papilionaceae (pa-pil-ee-uh-NAY-see-ee) (Info)
Genus: Robinia (roh-BIN-ee-uh) (Info)
Species: hispida (HISS-pih-duh) (Info)



Foliage Color:

Unknown - Tell us

Bloom Characteristics:

This plant is attractive to bees, butterflies and/or birds

Flowers are fragrant

Water Requirements:

Average Water Needs; Water regularly; do not overwater

Where to Grow:

Grow outdoors year-round


24-36 in. (60-90 cm)

36-48 in. (90-120 cm)

4-6 ft. (1.2-1.8 m)

6-8 ft. (1.8-2.4 m)

8-10 ft. (2.4-3 m)


20-30 ft. (6-9 m)


USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Sun Exposure:

Full Sun


Seed is poisonous if ingested

Parts of plant are poisonous if ingested

Bloom Color:


Magenta (Pink-Purple)

Bloom Time:

Late Spring/Early Summer


Grown for foliage



Other details:

May be a noxious weed or invasive

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

Patent Information:


Propagation Methods:

From hardwood cuttings

From seed; direct sow outdoors in fall

Seed Collecting:

Allow pods to dry on plant; break open to collect seeds

Seed does not store well; sow as soon as possible


This plant has been said to grow in the following regions:

Daleville, Alabama

Opelika, Alabama

Oakland, Arkansas

Winslow, Indiana

Mc Dowell, Kentucky

Taylorsville, Kentucky

West Monroe, Louisiana

Gladwin, Michigan

Lake, Michigan

Piedmont, Missouri

Oak Island, North Carolina

Dayton, Ohio

Kellyville, Oklahoma

Beaverton, Oregon

Spartanburg, South Carolina

Breckenridge, Texas

show all

Gardeners' Notes:


On Mar 27, 2016, coriaceous from ROSLINDALE, MA wrote:

This plant isn't much to look at except in bloom. The flowers are lovely but their season is short, and they are not fragrant. The leaves are armed with sharp spines.

Spreads aggressively by rhizomes when grown on its own roots---plants in nurseries are often grafted on R. pseudoacacia to reduce suckering. Rarely produces seed in cultivation. Good for stabilizing dry infertile slopes. The brittle stems are subject to wind damage.

At tallest, this species doesn't get much over 10'. Any 30' trees with similar pink/purple flowers are likely a hybrid with R. pseudoacacia.


On Jun 9, 2004, Fran99 from Spartanburg, SC wrote:

This Robinia is a pest in my yard. Yes, the pink flowers are lovely but that's the only thing about it that is. It's coming up in the shrubs, the flower beds, the yard. And the thorns will hurt you. Very aggessive here in the southeast US. I try not to use chemicals in the yard but might have to with this one.


On Jun 6, 2004, mylesm from Bowen Island,
Canada wrote:

I have seen this plant/tree in a couple of locations around Vancouver, BC. They are trees about 30' high and 20' spread. Gorgeous when in bloom. A few years ago I walked by a house being renovated and saw the yard was starting to get dug up. In one area where the excavator had ripped up some of the soil, was what looked to be a small Rose Acacia, with a few blooms. Rather than see it plowed under, I grabbed it and tore it and a few of the smaller root attachments out and took it home to replant.
The next day, the excavator flattened every plant on the lot!
The interesting thing about these ones, is that the stems appear to be bristling with millions of vicious looking thorns. However, when touching them, they are actually quite soft. My Rose Acacias (only 2 stems sur... read more


On Apr 25, 2004, Toxicodendron from Piedmont, MO (Zone 6a) wrote:

This plant is originally a native from Georgia, Kentucky, Virginia, and Alabama. It has been cultivated and escaped from cultivation so that now it is found practically over the whole eastern half of the United States. I got this plant from my Mother in Law many years ago. It grows into a small tree and spreads by runners. Not particularly attractive except when in bloom. If possible, locate on a hill where a path runs below it, that way you can really appreciate the blooms. It is slightly difficult to transplant because the young plants do not form their own root system while small, instead they rely on the runner from the mother plant. Best method is to sever the runner, then allow the small plant to form it's own roots...then move the plant the next year.