WateringTimesWatering plan, $19
Hesperocyparis macnabiana (Cupressus macnabiana), WUCOLS IV

How often to water MacNab cypress in California

In July in the Central Valley, established MacNab cypress 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. MacNab cypress is a California native of chaparral and foothill woodland in the inner north Coast Ranges and the northern Sierra foothills. It grows as a large evergreen shrub or small tree, often wider than tall, with flat sprays of gray, spicy-scented foliage. In the wild it grows on dry slopes and flats. Once rooted it needs little summer water.

TreeCalifornia nativeRated for 3 of 6 zones

How often to water MacNab cypress, 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 MacNab cypress 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 4 to 6 inches down around a first-year plant means its root ball is ready for a deep soak
  • Limp, drooping new shoots on a young plant in summer heat, over dry soil, point to a dried-out root ball
  • Short, needle-like leaves on a first-year seedling are normal juvenile growth, not a sign of thirst
  • Soil still damp a hand's depth down days after a soak means an established plant is getting more than it needs
  • An established plant that stays gray and fresh through a dry summer needs no extra water

How to water it

  • Build a shallow basin around a new cypress and soak the root ball and the soil just beyond it
  • Let water sink about 18 inches deep, then allow the top several inches to dry before the next soak
  • Shift water toward the outer edge of the root zone as the crown widens, keeping the trunk base dry
  • Plant in sand or clay on a slope or flat that sheds water, away from low spots that stay soggy
  • Keep lawn sprinklers and thirsty bedding plants off the root zone once the plant is established

Through the seasons

Give a new MacNab cypress deep soakings through its first summer, while roots grow out of the nursery root ball. One year of watering can be enough to establish it. After that it needs little summer water. It stays evergreen, so its gray foliage is present all year. Winter rain covers the cool months on the north-central coast, in the Central Valley and on the south coast. WUCOLS rates MacNab cypress very low water on the north-central coast. It rates low water in the Central Valley and low water on the south coast. WUCOLS marks it as not suited to South Inland. WUCOLS has not evaluated it for the high desert or the low desert.

In pots

MacNab cypress grows into a large shrub or tree, so a container suits only a young plant waiting for its place in the ground. Check the nursery can 2 inches down every few days in summer, and daily during a Central Valley heat wave. Water until it drains from the holes, then empty the saucer. A black can on hot paving heats quickly, so set it where the pot sides stay shaded. In winter, let the mix dry further between soakings, and skip watering after a good rain.

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
0.270.540.801.10.16JAN0.26FEB0.43MAR0.61APR0.83MAY0.99JUN1.07JUL0.95AUG0.72SEP0.47OCT0.22NOV0.14DEC0.270.540.801.10.16JFM0.61AMJ1.07JAS0.47OND
Gallons per square foot per month, Central Valley. Peak 1.07 in Jul, 6.84 a year.

Monthly water need by climate zone

MacNab Cypress: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.040.160.31–––
Feb0.050.260.32–––
Mar0.090.430.46–––
Apr0.120.610.56–––
May0.150.830.64–––
Jun0.160.990.69–––
Jul0.161.070.79–––
Aug0.150.950.74–––
Sep0.120.720.6–––
Oct0.090.470.46–––
Nov0.050.220.33–––
Dec0.030.140.26–––
Year1.26.846.2–––

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 MacNab cypress. 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 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 MacNab cypress, 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 MacNab cypress in summer?

In July, established MacNab cypress in loam needs a deep watering about every 20 days in the Central Valley and about every 27 days on the south coast. 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 MacNab cypress need per day?

In July in the Central Valley, established MacNab cypress 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 MacNab cypress change across California?

Yes. WUCOLS rates MacNab cypress separately for each of the six California climate zones: very low water in the North-Central Coastal zone, low water in the Central Valley zone, low water in the South Coastal zone, not suited to this region 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 MacNab cypress the same as Cupressus macnabiana?

Yes. The species has moved between genera and is sold as Hesperocyparis, Cupressus or Callitropsis macnabiana. It is also called Shasta cypress. All of these names refer to the same native cypress.

How big does MacNab cypress get?

Most plants reach 10 to 40 feet tall, with a spreading crown often wider than tall. It can grow fast to about 12 feet, then slows down. Plant it where it has room on all sides.

Does MacNab cypress grow in clay soil?

Yes. It tolerates sand and clay, often over rocky ground, and handles fast to slow drainage. Clay holds water longer, so check deeper and soak less often than in sand.

How cold hardy is MacNab cypress?

It handles cold well. One native plant nursery reports no damage at 0 degrees F. Cold winters are not a reason to water it more.

Why does MacNab cypress smell so strong?

Its foliage has a strong, spicy, resinous scent. Each tiny scalelike leaf carries a white resin gland on its center. The scent is normal and not a sign of stress.

Can MacNab cypress grow in partial shade?

Yes. It grows in full sun or partial shade. Soil in shade dries more slowly, so a first-year plant there needs fewer soakings.

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Sources