WateringTimesWatering plan, $19
Quercus berberidifolia, WUCOLS IV

How often to water California scrub oak in California

In July in the Central Valley, established California scrub oak in loam needs a deep soak only about once a month or less: about 8.8 gallons each time for a plant 4 feet across. California scrub oak is a slow-growing, long-lived evergreen native of dry, rocky slopes in coastal mountains and foothills. It usually forms a dense mound 8 to 10 feet tall and a bit wider, with small, leathery, holly-like leaves edged with spiny teeth. Small, fat acorns follow its late winter flowers. Once established, it needs little or no summer water.

ShrubCalifornia nativeRated for 5 of 6 zones

How often to water California scrub 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 California scrub 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

  • Leathery leaves on California scrub oak staying firm and dark through a dry summer show it needs no water
  • A young plant drooping new shoots while the soil is dry several inches down needs a deep soak
  • Leaves yellowing and dropping on soil kept wet in summer point to overwatering
  • An open, scraggly young plant is normal and fills in with age

How to water it

  • Water young plants deeply but only now and then during their first summers
  • Taper off to little or no summer water once it is established
  • Plant in full sun to part shade in well-drained soil
  • Keep it away from lawn sprinklers and drip lines that run all summer
  • Leave fallen leaves under the canopy as mulch

Through the seasons

Water a young plant now and then through its first few summers. After that it needs little or no irrigation, and summer drought is its normal state. It is evergreen and flowers from late winter to early spring. Winter rain covers its needs on the coast and in the Central Valley. WUCOLS rates California scrub oak very low water on the north-central coast, in the Central Valley and on the south coast. South Inland and the high desert carry the same low water rating. WUCOLS marks it as not suited to the low desert.

In pots

California scrub oak is best in the ground, but a seedling can grow in a deep pot for a year or two while it builds roots. Use a well-drained mix with some grit. Water when the mix is dry several inches down, then let it drain. In summer, check every few days. Never leave water in the saucer. Plant it out at the start of the rainy season so winter rain can settle it.

1 Your climate zone six WUCOLS zones, each from its own reference city
0.27gal per sq ft in JulyVery low water use in the Central Valley zone
A year
1.71 gal per sq ft
Reference
Sacramento climate table
Counts
Plant need, before sprinkler losses
0.300.610.921.20.04JAN0.07FEB0.11MAR0.15APR0.21MAY0.25JUN0.27JUL0.24AUG0.18SEP0.12OCT0.06NOV0.03DEC0.300.610.921.20.04JFM0.15AMJ0.27JAS0.12OND
Gallons per square foot per month, Central Valley. Peak 0.27 in Jul, 1.71 a year.

Monthly water need by climate zone

California Scrub Oak: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.040.040.080.310.3–
Feb0.050.070.080.350.37–
Mar0.090.110.110.520.58–
Apr0.120.150.140.640.76–
May0.150.210.160.780.95–
Jun0.160.250.170.921.14–
Jul0.160.270.211.22–
Aug0.150.240.190.931.12–
Sep0.120.180.150.740.86–
Oct0.090.120.110.530.58–
Nov0.050.060.080.360.37–
Dec0.030.030.070.270.26–
Year1.21.711.557.378.51–

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 very low water in the Central Valley, like California scrub oak. Plants that drink alike can share one valve and one schedule.

OleanderNerium oleander ssp. & cvs.very low water, Central Valley0.27 gal/sq ft in JulyAgaveAgave americana (and thick-leaved relatives)very low water, Central Valley0.27 gal/sq ft in JulyCactusOpuntia spp. & cvs. (CA natives and non-natives)very low water, Central Valley0.27 gal/sq ft in JulySpanish BroomSpartium junceumvery low water, Central Valley0.27 gal/sq ft in JulyPearl AcaciaAcacia podalyriifoliavery low water, Central Valley0.27 gal/sq ft in JulyBig SagebrushArtemisia tridentatavery low water, Central Valley0.27 gal/sq ft in JulyNuttall's Scrub OakQuercus dumosavery low water, Central Valley0.27 gal/sq ft in JulyCreosote BushLarrea tridentata ssp. & cvs.very low water, Central Valley0.27 gal/sq ft in JulyPurple SageSalvia leucophylla ssp. & cvs.very low water, Central Valley0.27 gal/sq ft in JulyBlack SageSalvia mellifera ssp. & cvs.very low water, Central Valley0.27 gal/sq ft in JulyBeaked YuccaYucca rostrata ssp. & cvs.very low water, Central Valley0.27 gal/sq ft in JulyToyonHeteromeles arbutifolia ssp. & cvs.very low water, Central Valley0.27 gal/sq ft in JulyFox Tail AgaveAgave attenuata (and thin-leaved relatives)very low water, Central Valley0.27 gal/sq ft in JulySaltbushAtriplex (CA native species) & ssp. & cvs.very low water, Central Valley0.27 gal/sq ft in JulyOak TreesQuercus agrifoliavery low water, Central Valley0.27 gal/sq ft in JulySalt CedarTamarix aphyllavery low water, Central Valley0.27 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 California scrub 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 California scrub oak in summer?

In July, established California scrub oak in loam needs a deep watering about once a month or less 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 California scrub oak need per day?

In July in the Central Valley, established California scrub oak needs about 0.1 gallons a day for a plant 4 feet across and about 0.4 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 California scrub oak change across California?

Yes. WUCOLS rates California scrub oak separately for each of the six California climate zones: very low water in the North-Central Coastal zone, very 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.

How is California scrub oak different from Nuttall's scrub oak?

Its leaves have only a few hairs underneath. Its acorns are small and fat, not narrow. Both were once lumped under Quercus dumosa.

Can California scrub oak be a hedge?

Yes, it can be trimmed into a formal hedge or left as an informal screen. It can also be raised into a small shade tree. Growth is slow, so trimming is light.

Is California scrub oak deer resistant?

It is deer tolerant. It is also long-lived and tough. It suits wild edges near native habitat.

How big does California scrub oak get?

It usually grows 4 to 10 feet tall and wide. Some plants become 15 to 20 foot trees. Growth is slow.

Why does my young scrub oak look scraggly?

Young plants are often open and thin. They fill in with age into a dense mound. Give it time rather than extra water.

More plant watering guides

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Sources