WateringTimesWatering plan, $19
Quercus arizonica, WUCOLS IV

How often to water Arizona white oak in California

In July in the Central Valley, established Arizona white 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. Arizona white oak comes from the Southwest and Mexico, not California. In low canyons it becomes a tree 30 to 60 feet tall with stout, spreading branches and a rounded crown, while at high elevations it stays shrubby. Its leathery leaves are blue-green above and duller below, and it keeps most of them through winter.

TreeRated for 2 of 6 zones

How often to water Arizona white 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 Arizona white 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

  • When a newly planted Arizona white oak has dry soil well below the mulch in summer, give it a long, slow soak
  • Leaves wilting or browning on a young tree in a heat wave can signal thirst
  • Leaf edges crisping in hot wind on a young tree suggest dry soil
  • Yellowing leaves and dieback over soggy ground point to poor drainage

How to water it

  • Give a young tree long, slow soaks with dry spells between
  • Once it is settled, water only when a dry stretch drags on
  • Plant in full sun in well-drained soil
  • Leave room for its broad, spreading crown
  • Leave fallen leaves under the canopy as mulch

Through the seasons

Through its first few summers, a young tree needs regular deep watering. Established trees need only occasional deep soaks, more in the hot interior than near the coast. It holds most of its leaves all year, and acorns mature in a single season. WUCOLS rates Arizona white oak low water on the north-central coast. The Central Valley carries a moderate water rating. WUCOLS has not evaluated it for the south coast, South Inland, the high desert or the low desert.

In pots

Arizona white oak becomes a broad tree, so a pot only suits a seedling for a short time. Pick a deep container and a gritty, fast-draining mix. When the upper few inches feel dry, water until it streams from the holes. In summer heat, a small pot can dry in a few days, so look at it often. Pour off any saucer water. In winter, rain usually covers it. Move it into the ground while it is small.

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
0.671.32.02.70.4JAN0.65FEB1.09MAR1.52APR2.08MAY2.48JUN2.67JUL2.39AUG1.8SEP1.18OCT0.56NOV0.34DEC0.671.32.02.70.4JFM1.52AMJ2.67JAS1.18OND
Gallons per square foot per month, Central Valley. Peak 2.67 in Jul, 17.11 a year.

Monthly water need by climate zone

Arizona White Oak: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.150.4––––
Feb0.210.65––––
Mar0.351.09––––
Apr0.471.52––––
May0.582.08––––
Jun0.642.48––––
Jul0.642.67––––
Aug0.62.39––––
Sep0.51.8––––
Oct0.351.18––––
Nov0.190.56––––
Dec0.120.34––––
Year4.817.11––––

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 Arizona white oak. Plants that drink alike can share one valve and one schedule.

Similar plants that need less water 16

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

Minutes for your sprinklers

Turn this into minutes on your water days

Every city page has a calculator that takes Arizona white 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 Arizona white oak need per day?

In July in the Central Valley, established Arizona white 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 Arizona white oak change across California?

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

Is Arizona white oak evergreen?

It is evergreen or nearly so. It holds its leathery leaves through winter. They are blue-green above and duller below.

How big does Arizona white oak get?

In low canyons it can reach 30 to 60 feet. At high elevations it may stay a shrub. Its branches spread wide.

Where is Arizona white oak native?

It is native to Arizona, east to New Mexico and southwestern Texas, and south into Mexico. It is not a California native. It grows in sun in its home range.

How long do Arizona white oak acorns take to ripen?

The acorns mature in one year. They sit in deep, hairy cups. They are solitary or paired.

Does Arizona white oak need full sun?

Yes, it is grown in sun. Plant it in an open spot. Give its spreading crown room.

More plant watering guides

Sources