How often to water necklace tree in California
In July in the Central Valley, established necklace tree in loam needs a deep watering about every 20 days: about 55 gallons each time under a 10 foot canopy, about 19 gallons a week. Necklace tree, also sold as Eve's necklace or Texas sophora, is a deciduous small tree or large shrub in the bean family from the south central United States. Fragrant rosy pink flowers hang in wisteria-like clusters in spring. Black pods pinched like strings of beads follow and stay on through winter. It is very heat and drought tolerant once established, but its soil must drain well.
How often to water necklace tree, month by month
Type your city above and the days between waterings and the gallons appear here, worked out from your city's climate table. Or read the figures by climate zone further down.
How this is worked out: established roots fill the top 1.5 feet of soil, and you water again when that soil has dried halfway. Loam soil holds about 1.5 inches of water per foot. Water the whole area under the branches, and skip a watering after a good soaking rain.
How to tell it needs water
- Soil dry 4 inches down around a young necklace tree in summer heat means its roots need a deep soak
- Leaflets drooping on a young tree late on a hot day, and still limp the next morning, point to a dry root zone
- Pale, yellowing leaves on a tree in heavy, slow draining soil signal chlorosis from poor drainage, not thirst
- Ground that stays soggy for days after a soak is a warning to cut back, since wet roots turn the leaves yellow
- Leaves dropping in fall while the bead-like pods hang on is the normal deciduous cycle, not a water problem
How to water it
- Water a young tree slowly over its root ball and just past it, widening the soaked ring as the branches spread
- Soak deeply, then let the soil dry several inches down before the next watering
- Plant in clay, loam or sand that drains well, and avoid low spots where winter rain stands
- Lay a ring of wood chip mulch over the root zone, pulled back from the thin bark, which is easily damaged
- On a multi-trunked tree, set emitters around the outer edge of the canopy rather than against the trunks
Through the seasons
Give a new necklace tree deep soakings through its first two summers, then stretch the gaps as the roots spread. An established tree is very heat and drought tolerant. Flowers open in early to mid spring and last about two weeks. Black pods form from midsummer into fall and stay on the bare branches through winter, when the tree needs little water. WUCOLS rates it low water in the Central Valley, where winter rain covers the cool months. WUCOLS has not evaluated it for the north-central coast, the south coast, South Inland, the high desert or the low desert.
In pots
Necklace tree can be grown in a container, though in the ground it reaches 15 to 35 feet, and most stay much shorter. Check the mix 2 to 3 inches down every few days in summer, and daily in Central Valley heat. Water until it drains from the holes, then empty the saucer, since soggy mix yellows the leaves. Repot when growth slows, a sign the roots have filled the pot. In winter the bare tree needs only occasional water, so let the mix dry well between soaks.
- A year
- 6.84 gal per sq ft
- Reference
- Sacramento climate table
- Counts
- Plant need, before sprinkler losses
Monthly water need by climate zone
Necklace Tree: gallons per square foot per month, by WUCOLS climate zone
| Month | N. Coast | C. Valley | S. Coast | S. Inland | Hi Desert | Lo Desert |
|---|---|---|---|---|---|---|
| Jan | – | 0.16 | – | – | – | – |
| Feb | – | 0.26 | – | – | – | – |
| Mar | – | 0.43 | – | – | – | – |
| Apr | – | 0.61 | – | – | – | – |
| May | – | 0.83 | – | – | – | – |
| Jun | – | 0.99 | – | – | – | – |
| Jul | – | 1.07 | – | – | – | – |
| Aug | – | 0.95 | – | – | – | – |
| Sep | – | 0.72 | – | – | – | – |
| Oct | – | 0.47 | – | – | – | – |
| Nov | – | 0.22 | – | – | – | – |
| Dec | – | 0.14 | – | – | – | – |
| Year | – | 6.84 | – | – | – | – |
How this is worked out: the WUCOLS water rating for each zone times that zone’s climate for the month. A dash means WUCOLS does not rate the plant there. The figures are what the plant uses, before sprinkler losses.
Plants with the same water needs 16
Rated low water in the Central Valley, like necklace tree. Plants that drink alike can share one valve and one schedule.
Olive TreesOlea europaea ssp. & cvs.low water, Central Valley1.07 gal/sq ft in July
Fig TreesFicus carica ssp. & cvs.low water, Central Valley1.07 gal/sq ft in July
Crape MyrtleLagerstroemia spp., hybrids & cvs.low water, Central Valley1.07 gal/sq ft in July
AloeAloe spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
Pomegranate TreesPunica granatumlow water, Central Valley1.07 gal/sq ft in July
EucalyptusEucalyptus polyanthemoslow water, Central Valley1.07 gal/sq ft in July
Pine TreesPinus canariensislow water, Central Valley1.07 gal/sq ft in July
JunipersJuniperus spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
Texas Red OakQuercus buckleyilow water, Central Valley1.07 gal/sq ft in July
Portuguese OakQuercus faginealow water, Central Valley1.07 gal/sq ft in July
Soapbark TreeQuillaja saponarialow water, Central Valley1.07 gal/sq ft in July
Bailey AcaciaAcacia baileyanalow water, Central Valley1.07 gal/sq ft in July
Silver WattleAcacia dealbatalow water, Central Valley1.07 gal/sq ft in July
Green WattleAcacia decurrenslow water, Central Valley1.07 gal/sq ft in July
Sydney Golden WattleAcacia longifolialow water, Central Valley1.07 gal/sq ft in July
Blackwood AcaciaAcacia melanoxylonlow water, Central Valley1.07 gal/sq ft in JulyTurn this into minutes on your water days
Every city page has a calculator that takes necklace tree, your sprinkler type and the month, and gives the minutes per water day for that supplier's schedule. Or put it in a zone of the personal watering plan and get all twelve months printed.
Questions people ask
How much water does necklace tree need per day?
In July in the Central Valley, established necklace tree needs about 2.7 gallons a day under a 10 foot canopy and about 11 gallons a day under a 20 foot canopy. Give it in deep waterings spread days apart rather than a little every day, so the whole root zone gets wet.
Does watering for necklace tree change across California?
Yes. WUCOLS rates necklace tree separately for each of the six California climate zones: not evaluated in the North-Central Coastal zone, low water in the Central Valley zone, not evaluated in the South Coastal zone, not evaluated in the South Inland zone, not evaluated in the High and Intermediate Desert zone, not evaluated in the Low Desert zone. The monthly table above shows how the same rating translates into different gallon amounts as reference evapotranspiration changes.
Are necklace tree seeds poisonous?
Yes. The seeds are poisonous, and the flowers are listed as poisonous too. Swallowed seeds can cause vomiting, diarrhea, excitement, delirium and coma. Keep the bead-like pods away from children and pets.
Why is it called necklace tree?
The black seed pods are pinched between the seeds, so they hang like strings of beads. They appear from midsummer into fall. They stay on the tree after the leaves drop.
Why are my necklace tree leaves turning yellow?
Poor drainage is a likely cause, since the leaves turn chlorotic in soil that holds water. Check whether the ground stays wet long after a soak. Water less often and improve drainage before trying other fixes.
Does necklace tree need full sun?
It grows in full sun or part shade and can serve as an understory tree. Flowering is heavier in full sun. Trees in sun also tend to stay shorter than those in shade.
Do I need to prune a necklace tree?
Its branches sit low on the trunk, so prune them where people or cars pass beneath. It is often grown with several trunks. Work carefully, since the thin bark is easily damaged.
More plant watering guides
Sources
- WUCOLS IV plant water use classification for Sophora affinis, the University of California survey California agencies use for landscape plan reviewRead August 23, 2026 on wucols.ucdavis.edu
- Model Water Efficient Landscape Ordinance, adopted text and appendices, effective 2025-01-02 · monthly reference evapotranspiration per city, Appendix CRead August 23, 2026 on water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/Water-Use-And-Efficiency/MWELO-Rulemaking/Final-MWELO-Text-and-Appendices_20250103.pdf
- UC Statewide IPM Program, irrigation scheduling using evapotranspirationRead September 30, 2026 on ipm.ucanr.edu/PMG/GARDEN/ENVIRON/evap.html
- Shaw and Pittenger, Landscape Irrigation System Evaluation and Management, UC Cooperative Extension, 2009Read September 30, 2026 on ucanr.edu/sites/default/files/2013-02/160836.pdf
- Pittenger, Water Management in Gardens and Landscapes, UC Riverside, 2017Read September 30, 2026 on ucanr.edu/sites/default/files/2017-03/258022.pdf