How often to water Texas red oak in California
In July in the Central Valley, established Texas red oak 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. Texas red oak is a deciduous oak native to limestone ridges and slopes from south-central Texas to north-central Oklahoma. Its glossy, deeply lobed leaves end in bristle-tipped teeth and turn red in fall. It is more drought tolerant than Shumard oak, but a young tree needs deep soakings while its taproot grows.
How often to water Texas red oak, 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
- Probe beside a young tree's root ball, and if the soil 6 inches down is dry, it is time for a slow, deep soak
- Young leaves that wilt and crisp at the edges during a hot spell, over dry ground, show the root ball ran dry
- Clusters of light brown mushrooms at the trunk base, or white fans of fungus under the bark, point to Armillaria root rot
- Leaves dusted white have powdery mildew, a fungal problem rather than a watering one
- Leaves turning red or brown and falling in fall are normal for this deciduous oak, not a sign of drought
How to water it
- Water a young tree over its root ball and a ring beyond it, widening the ring as the roots spread
- Soak slowly until water reaches 18 inches or more, then let the soil dry partway down, but never let it dry out completely
- Keep lawn and its sprinklers out of a mulched, turf-free zone reaching the drip line
- Plant in full sun in soil that drains, whether loam, clay or limestone-based, avoiding spots where water stands
- Shift drip emitters toward the canopy edge as the tree grows, keeping water off the trunk
Through the seasons
Soak a new tree deeply through its first few summers, widening the wet zone as roots spread. Once established it needs less frequent deep water, but the soil should never dry out completely. Leaves emerge in spring, turn red in fall and drop, and acorns ripen in their second year. Winter rain covers the dormant months on the north-central coast and in the Central Valley. WUCOLS rates Texas red oak moderate water on the north-central coast and low water in the Central Valley. WUCOLS marks it as not suited to the south coast. It has not been evaluated for South Inland, the high desert or the low desert.
In pots
A Texas red oak belongs in a pot only as a seedling, because its taproot heads straight down. Sow fresh acorns in a tall container with open drainage holes. Through summer, push a finger 2 inches into the mix every few days, and water once it feels dry there. Check more often in Central Valley heat. Let water run out the bottom, then pour off the saucer. Plant it out while young, before roots circle the pot. Over winter the leafless seedling needs only an occasional drink.
- A year
- 6.84 gal per sq ft
- Reference
- Sacramento climate table
- Counts
- Plant need, before sprinkler losses
Monthly water need by climate zone
Texas Red Oak: gallons per square foot per month, by WUCOLS climate zone
| Month | N. Coast | C. Valley | S. Coast | S. Inland | Hi Desert | Lo Desert |
|---|---|---|---|---|---|---|
| Jan | 0.37 | 0.16 | – | – | – | – |
| Feb | 0.53 | 0.26 | – | – | – | – |
| Mar | 0.87 | 0.43 | – | – | – | – |
| Apr | 1.18 | 0.61 | – | – | – | – |
| May | 1.46 | 0.83 | – | – | – | – |
| Jun | 1.61 | 0.99 | – | – | – | – |
| Jul | 1.61 | 1.07 | – | – | – | – |
| Aug | 1.49 | 0.95 | – | – | – | – |
| Sep | 1.24 | 0.72 | – | – | – | – |
| Oct | 0.87 | 0.47 | – | – | – | – |
| Nov | 0.47 | 0.22 | – | – | – | – |
| Dec | 0.31 | 0.14 | – | – | – | – |
| Year | 12 | 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 Texas red oak. 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
Portuguese OakQuercus faginealow water, Central Valley1.07 gal/sq ft in July
Soapbark TreeQuillaja saponarialow water, Central Valley1.07 gal/sq ft in July
Necklace TreeSophora affinislow 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 Texas red oak, 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 Texas red oak need per day?
In July in the Central Valley, established Texas red oak 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 Texas red oak change across California?
Yes. WUCOLS rates Texas red oak separately for each of the six California climate zones: moderate water in the North-Central Coastal zone, low water in the Central Valley zone, not suited to this region 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.
Is Texas red oak drought tolerant?
Fairly. It copes with drought better than Shumard oak, along with heat and alkaline soil. WUCOLS rates it low water in the Central Valley, but moderate water on the north-central coast. Even an established tree should not be left to dry out completely.
Why are mushrooms growing at the base of my Texas red oak?
Clusters of light brown honey mushrooms at the trunk base can mean Armillaria root rot, which can attack this oak. Waterlogged soil from too much summer irrigation raises the risk. Cut back watering, fix drainage and have an arborist inspect the tree.
Can Texas red oak grow in a lawn?
Frequent lawn watering can keep the soil under it too wet, a common problem for drought-adapted trees. Keep turf out of a mulched ring that reaches the drip line. Let the soil under the tree dry partway between waterings.
Are Texas red oak acorns poisonous?
The leaves and acorns can be toxic to animals that eat them. Keep livestock and pets away from fallen acorns. The large acorn crops still feed wildlife.
How big does Texas red oak get?
It is a small to medium-sized tree, usually listed at up to about 50 feet tall. Plant it where it has room to spread, such as a large yard or park. Place emitters out toward the canopy edge as it grows.
Does Texas red oak need acidic soil?
No. It grows wild on limestone and tolerates alkaline, neutral and slightly acidic soils. Clay suits it too, as long as water does not stand.
More plant watering guides
Sources
- WUCOLS IV plant water use classification for Quercus buckleyi, 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