WateringTimesWatering plan, $19
Quercus virginiana, WUCOLS IV

How often to water southern live oak in California

In July in the Central Valley, established southern live oak in loam needs a deep watering about every 8 days: about 55 gallons each time under a 10 foot canopy, about 47 gallons a week. Southern live oak is a long-lived oak from the Atlantic and Gulf coasts. Its gnarled limbs spread far wider than the tree is tall. It holds its leathery leaves until the new ones push out in spring. It handles clay or sand, salt spray and wind, and it grows best with deep soaks rather than frequent sprinkling.

TreeRated for 6 of 6 zones

How often to water southern live oak, month by month

Your city
Canopy width
10 ft
Your soil

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.

Every month, on your water days. The personal plan prints this for southern live oak and the rest of your yard, on the days your water supplier allows.Get the plan for $19

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.

Which soil do you have?

Dig down a few inches, take a handful of moist soil and squeeze it.

  • Sandy: gritty, falls apart when you open your hand, will not form a ball.
  • Loam: forms a soft ball that crumbles when you poke it.
  • Clay: forms a firm, sticky ball and squeezes out into a ribbon between thumb and finger.

Still not sure? Pick loam. Most garden beds sit between sand and clay.

How to measure canopy width

A tree with its canopy width marked across the widest branches and the circle under it shaded blue

Measure across the branches, from the tips of the outer leaves on one side to the tips on the other. A tape works, or pace it out.

Water the whole circle under the branches, shown in blue. The gallons here cover that circle.

A wider canopy means more gallons each watering, not more waterings. While the tree is young, measure again each spring.

How to tell it needs water

  • Soil dry 2 feet down under the outer canopy in summer signals that a young live oak needs a deep soak
  • Leaves curling and turning dull gray green during a hot spell can indicate a dry root zone
  • Heavy leaf drop in summer, outside the normal spring change, can follow drought stress
  • Yellowing leaves and a thinning crown over soil that stays wet point to root rot
  • Leaves falling in spring as new ones emerge are normal for this oak and are not a sign of thirst

How to water it

  • Water beyond the drip line with soakers or emitters, keeping the trunk base dry
  • Soak the soil 18 inches to 2 feet deep, then let the upper soil dry before the next soak
  • Plant in well-drained clay or sandy soil with room for a canopy far wider than its height
  • Mulch broadly under the canopy and keep lawn sprinklers off the trunk
  • Move emitters outward each year as the spreading limbs widen the root zone

Through the seasons

Water a young southern live oak deeply through its first few summers while roots spread wide. Established trees need deep soaks in long dry spells but resent constant wet soil at the trunk. It drops last year's leaves in spring as new ones emerge, so spring leaf fall is normal. The tree tolerates periodic flooding and salt spray. Winter rain covers the cool months on the coast and in the Central Valley; check desert trees in dry winters. WUCOLS rates southern live oak moderate water on the north-central coast, in the Central Valley, on the south coast, in South Inland, the high desert and the low desert.

In pots

Southern live oak belongs in the ground, since it becomes a huge, spreading tree. A young one can spend a year in a large, deep container before planting out. Check the mix 2 inches down and water when it is dry, which can be every few days in summer heat. Water until it drains through, then empty the saucer so roots are not left sitting wet. In winter, water less and let rain help, but do not let the root ball dry out.

1 Your climate zone six WUCOLS zones, each from its own reference city
2.67gal per sq ft in JulyModerate water use in the Central Valley zone
A year
17.11 gal per sq ft
Reference
Sacramento climate table
Counts
Plant need, before sprinkler losses
0.761.52.33.00.4JAN0.65FEB1.09MAR1.52APR2.08MAY2.48JUN2.67JUL2.39AUG1.8SEP1.18OCT0.56NOV0.34DEC0.761.52.33.00.4JFM1.52AMJ2.67JAS1.18OND
Gallons per square foot per month, Central Valley. Peak 2.67 in Jul, 17.11 a year.

Monthly water need by climate zone

Southern Live Oak: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.370.40.780.780.740.78
Feb0.530.650.810.870.930.93
Mar0.871.091.151.31.461.52
Apr1.181.521.41.611.891.95
May1.462.081.611.952.392.45
Jun1.612.481.742.292.852.79
Jul1.612.671.982.513.042.85
Aug1.492.391.862.332.792.6
Sep1.241.81.491.862.142.08
Oct0.871.181.151.331.461.49
Nov0.470.560.840.90.930.96
Dec0.310.340.650.680.650.68
Year1217.1115.518.4121.2721.08

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 moderate water in the Central Valley, like southern live oak. Plants that drink alike can share one valve and one schedule.

Citrus TreesCitrus spp.moderate water, Central Valley2.67 gal/sq ft in JulyJapanese MapleAcer palmatummoderate water, Central Valley2.67 gal/sq ft in JulyAvocado TreesPersea americanamoderate water, Central Valley2.67 gal/sq ft in JulyMagnolia TreesMagnolia grandiflora ssp. & cvs.moderate water, Central Valley2.67 gal/sq ft in JulyPalm TreesSyagrus romanzoffiana (Arecastrum romanzoffianum)moderate water, Central Valley2.67 gal/sq ft in JulyApple TreesMalus spp. (edible) e.g, 'Anna' (low chill variety for low desert)moderate water, Central Valley2.67 gal/sq ft in JulyPeach TreesPrunus spp. ediblemoderate water, Central Valley2.67 gal/sq ft in JulyPersimmon TreesDiospyros kakimoderate water, Central Valley2.67 gal/sq ft in JulyAmur MapleAcer ginnalamoderate water, Central Valley2.67 gal/sq ft in JulyFernleaf MapleAcer japonicummoderate water, Central Valley2.67 gal/sq ft in JulyBox ElderAcer negundomoderate water, Central Valley2.67 gal/sq ft in JulyNorway MapleAcer platanoidesmoderate water, Central Valley2.67 gal/sq ft in JulyRed MapleAcer rubrummoderate water, Central Valley2.67 gal/sq ft in JulyChinese MapleAcer truncatummoderate water, Central Valley2.67 gal/sq ft in JulyRed BuckeyeAesculus paviamoderate water, Central Valley2.67 gal/sq ft in JulyRed HorsechestnutAesculus x carneamoderate water, Central Valley2.67 gal/sq ft in July

Similar plants that need less water 16

Rated lower than southern live oak in the Central Valley. Worth a look for a new bed or a lawn replacement.

Olive TreesOlea europaea ssp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyFig TreesFicus carica ssp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyCrape MyrtleLagerstroemia spp., hybrids & cvs.low water, Central Valley1.07 gal/sq ft in JulyAloeAloe spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyPomegranate TreesPunica granatumlow water, Central Valley1.07 gal/sq ft in JulyEucalyptusEucalyptus polyanthemoslow water, Central Valley1.07 gal/sq ft in JulyPine TreesPinus canariensislow water, Central Valley1.07 gal/sq ft in JulyJunipersJuniperus spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyTexas Red OakQuercus buckleyilow water, Central Valley1.07 gal/sq ft in JulyPortuguese OakQuercus faginealow water, Central Valley1.07 gal/sq ft in JulySoapbark TreeQuillaja saponarialow water, Central Valley1.07 gal/sq ft in JulyNecklace TreeSophora affinislow water, Central Valley1.07 gal/sq ft in JulyBailey AcaciaAcacia baileyanalow water, Central Valley1.07 gal/sq ft in JulySilver WattleAcacia dealbatalow water, Central Valley1.07 gal/sq ft in JulyGreen WattleAcacia decurrenslow water, Central Valley1.07 gal/sq ft in JulySydney Golden WattleAcacia longifolialow water, Central Valley1.07 gal/sq ft in July
Minutes for your sprinklers

Turn this into minutes on your water days

Every city page has a calculator that takes southern live 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 often should I water southern live oak in summer?

In July, established southern live oak in loam needs a deep watering about every 8 days in the Central Valley, about every 11 days on the south coast and about every 9 days in the South Inland zone. Sandy soil holds less water, so waterings come closer together. Clay stretches them. Check the soil before each watering and skip one after a soaking rain.

How much water does southern live oak need per day?

In July in the Central Valley, established southern live oak needs about 6.8 gallons a day under a 10 foot canopy and about 27 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 southern live oak change across California?

Yes. WUCOLS rates southern live oak separately for each of the six California climate zones: moderate water in the North-Central Coastal zone, moderate water in the Central Valley zone, moderate water in the South Coastal zone, moderate water in the South Inland zone, moderate water in the High and Intermediate Desert zone, moderate water in the Low Desert zone. The monthly table above shows how the same rating translates into different gallon amounts as reference evapotranspiration changes.

Why is my live oak dropping leaves in spring?

Southern live oak keeps its old leaves until new ones begin to leaf out. A flush of falling leaves in spring is normal. Water only if the soil is dry deep down.

How big does southern live oak get?

It can reach 40 to 80 feet tall, and its limbs can spread 40 to 100 feet wide. Most trees stay under 50 feet tall. Plant it only where that canopy has room.

Can southern live oak grow in a lawn?

It can, but frequent lawn watering keeps the trunk base wet and favors root rot. Keep sprinklers off the trunk and mulch a wide ring instead of turf. Give the tree its own deep soaks.

Is southern live oak good near the coast?

Yes, it tolerates salt spray and is quite wind resistant. It grows in both clay and sandy soil. Young trees still need regular checks until established.

What are the round growths on my live oak leaves?

They are likely insect galls, which mar the leaves but do not harm the tree's health. No change in watering is needed. Rake fallen galled leaves if you want a tidier look.

Is southern live oak a fire risk?

It has a high flammability rating. Do not plant it within the defensible space next to your home. Keep dead leaves raked away from structures.

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Sources