# Tough Bully (Sideroxylon tenax) > A thorny small tree of dunes and scrub with leaves silky gold to copper beneath, fragrant flowers that swarm with pollinators, and fruit for birds. Also called tough buckthorn, tough bumelia, Bumelia tenax. Category: Uncommon Yard Trees. Grown from seed by Blue Whale Trees. Web version: https://bluewhaletrees.com/plants/tough-bully/ ![Tough bully (Sideroxylon tenax) glossy oval leaves and clusters of green unripe fruit on a branch](https://bluewhaletrees.com/img/plants/tough-bully-h1610-800.jpg) *Photo: Karen Guin, CC BY 4.0 ยท [Wikimedia Commons](https://commons.wikimedia.org/wiki/File%3ASideroxylon_tenax_420510953.jpg)* ## Facts - Type: Small tree - Mature height: 12 to 30 ft - USDA hardiness zones: 8 to 10 - Grows wild in: Sandy barrens, the coast and dry uplands - Native range: Florida, Georgia, North Carolina and South Carolina - Sun: Full, Part - Soil moisture: Dry, Average - Growth rate: Medium - Traits: Drought tolerant, Salt tolerant, Wildlife value, Showy flowers, Rare - Sold as: Saplings, Seed Heights and zones are typical ranges for the species in cultivation; local conditions and seed source shift them. ## Availability Not yet priced online. Ask at captain@bluewhaletrees.com or leave an email on the web page to be told when it is listed. ## Notes Tough bully is a thorny small tree of the sapodilla family and a cousin of our gum bumelia. Its name, from the Latin for tough, fits a tree that thrives on dunes and in scrub, in drought, salty wind and poor sand. The undersides of its leaves are covered in silky hairs of gold to coppery brown, and its twigs bleed a milky sap when broken. North Carolina, at the north end of its range, lists it as threatened. Grow it where its silky leaf undersides can be seen, as a specimen or a thorny hedge on dry, sandy ground. ## Size, growth and what to expect Sources disagree on its pace: some call it fast in a garden, others slow, and wild plants in scrub grow slowly. Our growth estimator treats it as a medium grower, about a foot and a half a year. It makes a small tree of 12 to 30 feet with a crown 10 to 20 feet wide, or a bushy, thorny shrub on poor sand. It keeps its leaves in the south of its range and drops them farther north. Clusters of up to 40 tiny, fragrant white flowers open in May and June, and bees, wasps, flies and butterflies swarm to them. A native bee of the Florida scrub, described in 2011, seems to visit no other flower. The fruit ripens purplish black in late summer and fall, a third to half an inch long and sweet. Birds and mammals eat it. It grows wild on the coastal plain from southern North Carolina to Florida, on coastal dunes, in maritime forest and pinelands, and in inland scrub on deep sand. NatureServe ranks it vulnerable. ## How to grow Tough Bully Tough bully grows in full sun or part shade, in deep sand that drains fast. It takes long droughts and poor soil, and it stands salty wind, though not direct salt spray or flooding by salt water. Plant it 15 feet from a wall and at least 15 feet from overhead wires, and set trees 10 feet apart for a hedge. Saplings ship bare-root or potted. Plant them from late fall to early spring, in a hole wider than the roots and no deeper. Set the root flare at the soil line, put the native soil back in, and keep the mulch clear of the trunk. It can be grown from seed cleaned of its pulp. Chill the seed damp in the refrigerator for 60 days, as gum bumelia seed is treated. Sow it in spring under a light cover of soil. Water weekly through the first summer, then only in long droughts. Prune it young to one trunk for a small tree, or let it branch into a bushy shrub. Wear gloves, since the branches carry thorns. Each flower carries both male and female parts, and most buckthorns can pollinate themselves, so a single tree can set fruit. The larvae of the bumelia borer, a longhorn beetle, can tunnel into the base of buckthorn trunks. It has no other significant pests or diseases. ## Sources - [Florida Department of Agriculture and Consumer Services, Division of Plant Industry: The Buckthorns (Genus Sideroxylon), Circular FDACS-P-01915 (Corogin, October 2018)](https://www.fdacs.gov/content/download/82393/file/CIRCULAR_Buckthorns_SIderoxylon.pdf) - [NC State Extension Gardener Plant Toolbox: Sideroxylon tenax](https://plants.ces.ncsu.edu/plants/sideroxylon-tenax/) - [Florida Native Plant Society: Sideroxylon tenax, tough buckthorn, tough bully](https://www.fnps.org/plant/sideroxylon-tenax) - [Flora of North America, vol. 8: Sideroxylon tenax, tough bully](http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250092176) - [NatureServe Explorer: Sideroxylon tenax, Tough Bumelia](https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.156913/Sideroxylon_tenax) - [North Carolina Natural Heritage Program: 2024 Rare Plant List, revised 11/03/2025](https://www.ncnhp.org/media/833/open) - [USDA Forest Service, Woody Plant Seed Manual (2008), Sideroxylon chapter, gum bumelia (Bonner and Schmidtling)](https://rngr.net/publications/wpsm/genera/s/at_download/file) - [Atlas of Florida Plants, Institute for Systematic Botany: Sideroxylon tenax](https://florida.plantatlas.usf.edu/plant/species/3285) - [USDA NRCS PLANTS Database: Sideroxylon tenax](https://plants.usda.gov/plant-profile/SITE2) - [The Institute for Regional Conservation, Natives for Your Neighborhood: Sideroxylon tenax](https://www.regionalconservation.org/beta/nfyn/plantdetail.asp?tx=Sidetena) ## Read before planting - [Ten planting mistakes that quietly kill trees](https://bluewhaletrees.com/articles/ten-planting-mistakes/index.html.md) - [Transplanting young trees: timing, water and protection](https://bluewhaletrees.com/articles/transplanting-young-trees/index.html.md) - [Protecting young trees from voles, rabbits, deer and squirrels](https://bluewhaletrees.com/articles/protecting-trees-from-animals/index.html.md) - [Multistem or single stem? Sometimes the trunk is hiding the answer](https://bluewhaletrees.com/articles/multistem-or-single-stem/index.html.md) - [Leaf litter, not wood chips, under the canopy](https://bluewhaletrees.com/articles/leaf-litter-not-wood-chips/index.html.md) - [Native trees and shrubs for birds: caterpillars, fruit, mast, nests and winter cover, month by month](https://bluewhaletrees.com/articles/native-trees-for-birds/index.html.md) ## Related - [Planting-site check](https://bluewhaletrees.com/tools/site-check/index.html.md): for a thrive, struggle or fail verdict on Tough Bully, add ?species=tough-bully with zone (2 to 10), sun (full, part, shade) and moisture (dry, average, wet) to that address, for example ?species=tough-bully&zone=8&sun=part&moisture=average. - [Companion species for Tough Bully](https://bluewhaletrees.com/tools/companions/index.html.md?species=tough-bully): the natives that share its ground and the plants that pair with it in a yard. - [Growth estimator](https://bluewhaletrees.com/tools/growth/index.html.md): how the height and trunk projections are made; the estimate itself runs in the browser at https://bluewhaletrees.com/tools/growth/#species=tough-bully - [Seed sowing planner](https://bluewhaletrees.com/tools/sowing/index.html.md): how Tough Bully is sown, in the chart for every species (treatment, cold days, depth, timing); the dated plan runs in the browser at https://bluewhaletrees.com/tools/sowing/#species=tough-bully - [Pollination planner](https://bluewhaletrees.com/tools/pollination/index.html.md): what Tough Bully needs for a crop and how many to plant, in the table for every species; the planner runs in the browser at https://bluewhaletrees.com/tools/pollination/#plants=tough-bully:1 - [Bloom and fruit calendar](https://bluewhaletrees.com/tools/calendar/index.html.md): the months Tough Bully flowers and fruits, in the grid for every species.