WateringTimesWatering plan, $19
Sequoiadendron giganteum, WUCOLS IV

How often to water giant sequoia in California

In July in the Central Valley, established giant sequoia 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. Giant sequoia is a massive, long-lived conifer native to a narrow band of Sierra Nevada groves, where thick, fire-resistant bark lets some trunks stand for thousands of years. In gardens, it needs supplemental irrigation when rainfall does not keep the root area moist. Its fine, pale feeder roots sit close to the surface and bruise easily, and dry roots most often kill a young specimen.

TreeCalifornia nativeRated for 3 of 6 zones

How often to water giant sequoia, 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 giant sequoia 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

  • A young giant sequoia with dry soil in the top foot of its root area is overdue for a deep soak
  • Browning sequoia branch tips call for a soil check and an inspection for dieback or blight
  • Persistently muddy soil around a giant sequoia means drainage needs attention before more irrigation
  • Patchy dieback scattered through an otherwise healthy crown after a dry season is worth a soil check before you blame pests

How to water it

  • Spread water across the sequoia's root area to moisten its delicate surface feeder roots
  • Give the root area a long, slow soak reaching a foot down, then hold off until the upper soil has dried
  • Keep foot traffic, digging and tilling away from the base, since the fragile surface roots tear easily
  • Build up a generous mulch layer over the root area to buffer temperature swings and hold soil moisture longer
  • Push the irrigated circle farther out each year to track the tree's expanding canopy and root reach

Through the seasons

Watch a young giant sequoia closely through its first summers, because its shallow feeder roots must not dry out completely. Established trees also need moisture checks through California's dry season. The foliage stays green year round, but winter is a resting period. Coastal and Central Valley rain can reduce irrigation; check the soil during dry winter spells. WUCOLS rates giant sequoia moderate water on the north-central coast, in the Central Valley and in South Inland. WUCOLS marks it as not suited to the south coast, the high desert or the low desert.

In pots

Keep a nursery-grown sequoia in its container until the planting site is ready, preserving the root ball. Handle repotting gently, since the delicate feeder roots tear if disturbed too much. Press into the surface of the mix daily in hot weather, since a small volume of soil holds far less reserve water than open ground does. Run water slowly until it exits the drainage holes, then tip out the saucer. Ease back on watering as cooler weather slows growth, without letting the mix dry out completely.

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

Giant Sequoia: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.370.4–0.78––
Feb0.530.65–0.87––
Mar0.871.09–1.3––
Apr1.181.52–1.61––
May1.462.08–1.95––
Jun1.612.48–2.29––
Jul1.612.67–2.51––
Aug1.492.39–2.33––
Sep1.241.8–1.86––
Oct0.871.18–1.33––
Nov0.470.56–0.9––
Dec0.310.34–0.68––
Year1217.11–18.41––

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 giant sequoia. 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 giant sequoia 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 giant sequoia, 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 giant sequoia in summer?

In July, established giant sequoia in loam needs a deep watering about every 8 days in the Central Valley 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 giant sequoia need per day?

In July in the Central Valley, established giant sequoia 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 giant sequoia change across California?

Yes. WUCOLS rates giant sequoia separately for each of the six California climate zones: moderate water in the North-Central Coastal zone, moderate water in the Central Valley zone, not suited to this region in the South Coastal zone, moderate water in the South Inland zone, not suited to this region 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 giant sequoia different from coast redwood?

Giant sequoia and coast redwood belong to different genera and occur naturally in different parts of California. Giant sequoia retains a broader trunk higher up. Their WUCOLS water ratings also differ.

Why did my young giant sequoia die after a dry summer?

Young giant sequoias can die when their delicate feeder roots dry out. Check both the original root ball and the nearby soil during establishment. Older garden trees still need reliable soil moisture.

Can I grow giant sequoia away from the Sierra Nevada?

It grows in gardens outside the Sierra Nevada when climate and soil moisture suit it. Provide supplemental water when the soil needs it, following the WUCOLS rating for the region. Allow generous space for this large conifer.

Is giant sequoia resistant to fire and does that affect watering?

Thick bark helps protect mature giant sequoias from fire. Seedlings and saplings remain vulnerable, and fire resistance does not replace the need for moist soil.

Why shouldn't I dig or till near my giant sequoia?

Its fine feeder roots run near the surface and snap off easily, which can set back a young tree's ability to take up water. Keep cultivation and heavy foot traffic away from the root zone. Add mulch by hand instead of working it into the soil.

Can giant sequoia handle the desert heat in my yard?

WUCOLS marks giant sequoia as not suited to the high desert and the low desert. Extreme heat and aridity there go beyond what consistent watering alone can offset. Choose a tree rated for desert conditions instead.

More plant watering guides

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Sources