# Eve's Necklace (Styphnolobium affine)

> A small tree of limestone country with fragrant, rose-pink flowers like wisteria in spring and black pods like strings of beads, for dry, well-drained ground.

Also called Texas sophora, pink sophora, necklace tree, Eve's necklacepod, Sophora affinis. Category: Uncommon Yard Trees. Grown from seed by Blue Whale Trees. Web version: https://bluewhaletrees.com/plants/eve-necklace/

![Eve's necklace (Styphnolobium affine) small tree in bloom with hanging clusters of pale pink flowers](https://bluewhaletrees.com/img/plants/eve-necklace-h1610-800.jpg)
*Photo: sonnia hill, CC BY 2.0, cropped · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File%3AStyphnolobium_afine.jpg)*

## Facts

- Type: Small tree
- Mature height: 15 to 30 ft
- USDA hardiness zones: 7 to 9
- Grows wild in: Rocky ground, dry uplands, stream banks, the forest understory, old fields and edges
- Native range: [Arkansas](https://bluewhaletrees.com/tools/native/index.html.md?state=AR), [Louisiana](https://bluewhaletrees.com/tools/native/index.html.md?state=LA), [Oklahoma](https://bluewhaletrees.com/tools/native/index.html.md?state=OK) and [Texas](https://bluewhaletrees.com/tools/native/index.html.md?state=TX)
- Sun: Full, Part, Shade
- Soil moisture: Dry, Average
- Growth rate: Medium
- Flowers: March to May
- Fruit: Pods, August to November
- First crop: Under 10 years
- Mature spread: 20 ft
- Traits: Showy flowers, Winter interest, Drought tolerant, Wildlife value, Street tree
- Sold as: Saplings, Seed

Heights and zones are typical ranges for the species in cultivation; local conditions and seed source shift them.

## Availability

Saplings ship [bare-root](https://bluewhaletrees.com/articles/planting-bare-root-trees-on-arrival/index.html.md) or [in a pot](https://bluewhaletrees.com/articles/a-sapling-in-a-pot/index.html.md), [usually 12 to 18 inches tall](https://bluewhaletrees.com/articles/small-sapling-or-big-transplant/index.html.md), in the dormant season, and their height and age are stated with the price, once available. Live plants ship February to May and October to November. Not priced yet: leave an email on the web page for one email when it is priced, with a code for 10% off the plants in that order, not shipping or tax, or write to captain@bluewhaletrees.com.

## Notes

Eve's necklace is a small tree of limestone hills and stream banks from Oklahoma, Arkansas and Louisiana to central Texas. Its name comes from the black, beadlike pods that follow its sweet-scented pink spring flowers, which bees visit. It stands heat and drought and wants dry, well-drained ground in sun or part shade. Its pods give it winter interest, and it can serve as a small street tree where its low branches are pruned up. Use it as an accent tree, alone in a sunny lawn or bed, where it stays full instead of spindly.

## Size, growth and what to expect

Eve's necklace grows at a medium pace, about a foot and a half a year in our growth estimator. Expect 15 to 30 feet with an upright, oval crown 10 to 20 feet wide, often on several trunks. It is a short-lived tree.

Fragrant, rose-pink flowers hang in clusters like wisteria from March to May. The black pods, pinched between the seeds like a string of beads, ripen in late summer and fall and hang on into winter. Birds nest in its branches.

It grows wild from Oklahoma, Arkansas and Louisiana to north central and central Texas, mostly on limestone. It is found on rocky uplands, wooded slopes, stream banks, floodplains and roadsides. NatureServe ranks it imperiled to vulnerable in Arkansas and vulnerable in Oklahoma.

## How to grow Eve's Necklace

Eve's necklace grows in full sun, part shade or the shade of taller trees, but it flowers most in full sun. In dense shade it grows thin and almost vine-like. It takes clay, loam, sand and limestone soils, acid or alkaline. It stands heat and drought, but its soil must drain well, or its leaves turn yellow. Plant it 15 feet from a wall and at least 15 feet from overhead wires, and set trees 10 feet apart.

Saplings ship bare-root or potted. Plant them dormant, from leaf fall until bud swell, 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. Each seed has a hard coat, so nick it with a knife or file through the coat, then soak it in warm water until it swells. Sow it half an inch deep once the soil has warmed in spring. Seed that is only soaked, without nicking, comes up unevenly over two years.

Water weekly through the first summer, then only in long droughts. Keep mowers and string trimmers off the trunk, since the thin bark is easily damaged. Guard young trees with a tube or cage where deer are many, though deer browse it only moderately. Prune the low branches where people or cars must pass, or let it grow with several trunks.

Each flower carries both male and female parts, so there are no male and female plants to pair. Bees visit the flowers, which last about two weeks. It has no serious pests or diseases, but its roots send up suckers. The flowers and seeds are poisonous if eaten, and the seeds can cause vomiting and diarrhea, so keep them from children.

## Sources

- [NC State Extension Gardener Plant Toolbox: Styphnolobium affine](https://plants.ces.ncsu.edu/plants/styphnolobium-affine/)
- [Lady Bird Johnson Wildflower Center: Styphnolobium affine](https://www.wildflower.org/plants/result.php?id_plant=STAF4)
- [Flora of North America, vol. 11: Styphnolobium affine](http://floranorthamerica.org/Styphnolobium_affine)
- [Texas A&M Forest Service, Trees of Texas: Texas sophora](https://texastreeid.tfs.tamu.edu/content/TreeDetails/?id=119)
- [Texas A&M AgriLife Extension, Texas Native Plants Database: Eve's Necklace](https://aggie-horticulture.tamu.edu/ornamentals/natives/sophoraaffinis.htm)
- [UC Davis Arboretum and Public Garden, Texas tree trial database: Eve's Necklace](https://arboretum.ucdavis.edu/tree-database/eves-necklace-styphnolobium-affine)
- [USDA Forest Service, Woody Plant Seed Manual (2008), Sophora chapter](https://www.fs.usda.gov/nsl/Wpsm/Sophora.pdf)
- [NatureServe Explorer: Sophora affinis](https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.141601/Sophora_affinis)
- [USDA NRCS PLANTS Database: Styphnolobium affine](https://plants.usda.gov/plant-profile/STAF4)
- [NC State Extension Gardener Plant Toolbox: Styphnolobium japonicum, Japanese pagoda tree](https://plants.ces.ncsu.edu/plants/styphnolobium-japonicum/)

## 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)
- [How fast every tree and shrub we grow gets tall: growth rate, A to Z](https://bluewhaletrees.com/articles/growth-rates/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)

## Related

- Trees to plant it under: [Common Hackberry](https://bluewhaletrees.com/plants/common-hackberry/index.html.md), [Cedar Elm](https://bluewhaletrees.com/plants/cedar-elm/index.html.md) and [Rock Elm](https://bluewhaletrees.com/plants/rock-elm/index.html.md)
- [Planting-site check](https://bluewhaletrees.com/tools/site-check/index.html.md): for a thrive, struggle or fail verdict on Eve's Necklace, add ?species=eve-necklace with zone (2 to 10), sun (full, part, shade) and moisture (dry, average, wet) to that address; for example, the verdict for zone 7, part sun and average soil as Markdown is at https://bluewhaletrees.com/tools/site-check/index.html.md?species=eve-necklace&zone=7&sun=part&moisture=average
- [Companion species for Eve's Necklace](https://bluewhaletrees.com/tools/companions/index.html.md?species=eve-necklace): the natives that share its ground and the plants that pair with it in a yard.
- [Transplant planner](https://bluewhaletrees.com/tools/transplant/index.html.md?species=eve-necklace): whether Eve's Necklace can be moved and what the move takes, the root ball, its weight, who can lift it and the months, as Markdown at that address (add caliper= or height=, month= 1 to 12 and soil= sandy, loam or clay)
- [Growth estimator](https://bluewhaletrees.com/tools/growth/index.html.md): how the height and trunk projections are made; the estimate for Eve's Necklace as Markdown is at https://bluewhaletrees.com/tools/growth/index.html.md?species=eve-necklace (add height=, years= and site= poor, average or good)
- [Seed sowing planner](https://bluewhaletrees.com/tools/sowing/index.html.md): how Eve's Necklace is sown, in the chart for every species (treatment, cold days, depth, timing); the dated plan for it as Markdown is at https://bluewhaletrees.com/tools/sowing/index.html.md?species=eve-necklace (add state= and zone= for your own frost dates, method=fridge for the refrigerator route)
- [Pollination planner](https://bluewhaletrees.com/tools/pollination/index.html.md): what Eve's Necklace needs for a crop and how many to plant, in the table for every species; the verdict for 1 of them as Markdown is at https://bluewhaletrees.com/tools/pollination/index.html.md?plants=eve-necklace:1
- [Planting-window tool](https://bluewhaletrees.com/tools/planting-window/index.html.md): when to plant Eve's Necklace where you live, as a fall and a spring window from the local frost dates; the windows as Markdown are at https://bluewhaletrees.com/tools/planting-window/index.html.md?species=eve-necklace&state=MO&zone=6 with your own state and zone in place of those
- [Planting-distance tool](https://bluewhaletrees.com/tools/distance/index.html.md): how far Eve's Necklace goes from a house, a septic field, a walk, wires, a property line and the next tree; the distances as Markdown are at https://bluewhaletrees.com/tools/distance/index.html.md?species=eve-necklace&near=house,septic,pavement,wires,boundary,tree
- [Bloom and fruit calendar](https://bluewhaletrees.com/tools/calendar/index.html.md): the months Eve's Necklace flowers and fruits, in the grid for every species; its own row and the gaps of a planting with it as Markdown at https://bluewhaletrees.com/tools/calendar/index.html.md?plants=eve-necklace