WateringTimesWatering plan, $19
Quercus turbinella, WUCOLS IV

How often to water shrub live oak in California

In July in the Central Valley, established shrub live oak in loam needs a deep watering about every 20 days: about 8.8 gallons each time for a plant 4 feet across, about 3.0 gallons a week. Shrub live oak is a stiff, evergreen oak from the desert mountains, with small, spiny, gray-green leaves and purplish red new growth. It grows as a dense shrub and can spread by root sprouts into a thicket. Once its roots are established it needs little summer water, and it wants soil that drains well around its base.

ShrubCalifornia nativeRated for 5 of 6 zones

How often to water shrub live oak, month by month

Your city
Plant width
4 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 shrub 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 the plant covers, 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 plant width

A shrub with its width marked from one side to the other and the circle under it shaded blue

Measure across the plant, from the tips of the leaves on one side to the tips on the other.

Water the whole area the plant covers, shown in blue. The gallons here cover that area.

A wider plant means more gallons each watering, not more waterings. While it is young, measure again each spring.

How to tell it needs water

  • Soil dry 3 to 4 inches down at the edge of a young shrub live oak's root ball means it is ready for a deep soak
  • Drooping or browning shoot tips on a first-year plant during summer heat, with dry soil below, point to a thirsty root zone
  • Purplish red color on fresh shoots is the normal look of this oak's new growth, not a stress sign
  • Leaves that wilt or turn dull and yellow while the soil stays wet point to root rot, which more water will not fix

How to water it

  • Water a young shrub live oak over its root ball and a ring of soil just beyond it, widening the ring as the shrub fills out
  • Soak slowly until water reaches about 12 inches down, then let the soil dry several inches before the next soak
  • Use drip or a slow hose at the root zone, and keep spray and standing water away from the base of the stems
  • Plant it in sun in soil that drains well, and avoid low spots where winter water collects
  • Keep lawn and thirsty beds out of its root zone so an established plant stays on dry-summer care

Through the seasons

Give a new shrub live oak deep soakings through its first summer or two, widening the wet area as the roots spread. After that it needs only occasional summer water. It keeps its leathery leaves through winter, so it never has a bare season. Irrigation matters most from late spring through early fall, when the soil dries fast. Winter rain covers the cool months on the north-central coast, on the south coast and in the Central Valley. In the high desert, check the soil during long dry winter spells. WUCOLS rates shrub live oak low water on the north-central coast, in the Central Valley, in South Inland and in the high desert. It rates very low water on the south coast. WUCOLS marks it as not suited to the low desert.

In pots

Shrub live oak belongs in a container only while it is young, before it goes in the ground. Use a deep nursery can with open drainage holes and a gritty mix. Check the mix 2 to 3 inches down every few days in summer, and daily during Central Valley or desert heat waves. Water until it runs from the holes, then empty the saucer. A dark can on hot paving heats the roots, so shade the pot itself. In winter, let rain do most of the work and check that the mix is not staying soggy.

1 Your climate zone six WUCOLS zones, each from its own reference city
1.07gal per sq ft in JulyLow water use in the Central Valley zone
A year
6.84 gal per sq ft
Reference
Sacramento climate table
Counts
Plant need, before sprinkler losses
0.300.610.921.20.16JAN0.26FEB0.43MAR0.61APR0.83MAY0.99JUN1.07JUL0.95AUG0.72SEP0.47OCT0.22NOV0.14DEC0.300.610.921.20.16JFM0.61AMJ1.07JAS0.47OND
Gallons per square foot per month, Central Valley. Peak 1.07 in Jul, 6.84 a year.

Monthly water need by climate zone

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

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.150.160.080.310.3–
Feb0.210.260.080.350.37–
Mar0.350.430.110.520.58–
Apr0.470.610.140.640.76–
May0.580.830.160.780.95–
Jun0.640.990.170.921.14–
Jul0.641.070.211.22–
Aug0.60.950.190.931.12–
Sep0.50.720.150.740.86–
Oct0.350.470.110.530.58–
Nov0.190.220.080.360.37–
Dec0.120.140.070.270.26–
Year4.86.841.557.378.51–

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 shrub live oak. Plants that drink alike can share one valve and one schedule.

LavenderLavandula spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyRosemaryRosmarinus officinalislow water, Central Valley1.07 gal/sq ft in JulyBougainvilleaBougainvillea & spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyOlive TreesOlea europaea 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 JulyLantanaLantana camara ssp. & cvs.low water, Central Valley1.07 gal/sq ft in JulySalviaSalvia greggii ssp., cvs. & hybridslow water, Central Valley1.07 gal/sq ft in JulyAloeAloe spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulySucculentsEcheveria spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyJunipersJuniperus spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyRussian SagePerovskia spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulySagebrushArtemisia spp. (shrubby)low water, Central Valley1.07 gal/sq ft in JulyWild PrivetLigustrum vulgarelow water, Central Valley1.07 gal/sq ft in JulyCoralberrySymphoricarpos orbiculatus (SHADE)low water, Central Valley1.07 gal/sq ft in JulySydney Golden WattleAcacia longifolialow water, Central Valley1.07 gal/sq ft in JulyBlue Leaf WattleAcacia salignalow 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 shrub 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 shrub live oak in summer?

In July, established shrub live oak in loam needs a deep watering about every 20 days in the Central Valley, about once a month or less on the south coast and about every 22 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 shrub live oak need per day?

In July in the Central Valley, established shrub live oak needs about 0.4 gallons a day for a plant 4 feet across and about 1.7 gallons a day for a plant 8 feet across. Give it in deep waterings spread days apart rather than a little every day, so the whole root zone gets wet.

Does watering for shrub live oak change across California?

Yes. WUCOLS rates shrub live oak separately for each of the six California climate zones: low water in the North-Central Coastal zone, low water in the Central Valley zone, very low water in the South Coastal zone, low water in the South Inland zone, low water in the High and Intermediate Desert zone, not suited to this region in the Low Desert zone. The monthly table above shows how the same rating translates into different gallon amounts as reference evapotranspiration changes.

Is shrub live oak evergreen?

Yes. Each leathery leaf stays on the plant for more than one year, so it looks green and gray through winter. Fresh shoots open purplish red before turning the usual gray-green.

How big does shrub live oak get?

It usually grows 6 to 15 feet tall and about as wide. Plants in moist spots grow larger, so steady extra water tends to mean a bigger shrub. Give it room where it will not need constant cutting back.

Does shrub live oak spread?

Yes. It sends up sprouts from its roots and can form a thicket over time. Plant it where a dense mass is welcome, such as a dry bank or a hedge line.

Can shrub live oak grow in the low desert?

No. Of the six WUCOLS zones, the low desert is the one where this oak is not suited. In California it grows wild in desert mountains, mostly between about 3,900 and 6,600 feet. Choose a plant rated for low desert heat instead.

Are shrub live oak acorns a problem?

The acorns can be a nuisance where they drop on paths and patios. Rake them up, and keep them from piling over drip emitters. They do not change how the shrub should be watered.

More plant watering guides

Olive TreesFig TreesCrape MyrtleWisteriaLantanaSalviaIrisesAloe

Sources