WateringTimesWatering plan, $19
Liquidambar formosana, WUCOLS IV

How often to water Chinese sweet gum in California

In July in the Central Valley, established Chinese sweet gum 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. Chinese sweet gum, also called Formosa sweet gum, is a deciduous shade tree from southern China and Taiwan. It grows pyramidal when young, then rounds out at 40 to 60 feet. Glossy, three-lobed leaves open with a lavender tint in spring. It prefers deep, fertile soil that stays moist but drains, and it struggles in alkaline ground.

TreeRated for 4 of 6 zones

How often to water Chinese sweet gum, 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 Chinese sweet gum 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 sweet gum needs a deep soak when soil at the rim of its root ball is dry 4 to 6 inches deep
  • In summer heat, glossy leaves that droop or curl above dry ground show the roots need water
  • Yellowing leaves on a tree in alkaline soil often mean iron chlorosis, which more water will not fix
  • Wilting, yellowing leaves that fail to recover while the ground stays wet are a sign of root rot from waterlogged soil
  • Dark, sunken bark patches or oozing sap can mean canker, a disease that watering will not cure

How to water it

  • Wet a young sweet gum's root ball plus a ring of ground just outside it, moving the ring outward as the canopy grows
  • Run water slowly so it sinks to roughly 18 inches, and soak again once just the upper few inches have dried
  • Place drip emitters or a trickling hose beneath the outer branches, never letting spray hit the trunk or water pool against it
  • Plant in deep, fertile, well-drained soil that is not alkaline, in full sun
  • Give it a lawn or open area more than 6 feet wide, away from sidewalks its roots can lift

Through the seasons

Through its first summers, a young Chinese sweet gum needs deep soakings, with the wetted circle moving outward as roots extend. Even mature trees prefer deep soil that stays moist, so this is no dry-garden tree. In spring the new leaves unfold with a lavender tint, and small yellow-green flowers appear in April and May. Fall color ranges from red and yellow to a dull green. The spiny gum balls stay on through winter, dropping from about December to April. WUCOLS rates it moderate water across the north-central coast, the Central Valley, the south coast and South Inland. Along the coast and in the Central Valley, winter rain takes care of the cool months. WUCOLS has not evaluated it for the high desert or the low desert.

In pots

Chinese sweet gum becomes a large tree, so a container only works for a young plant awaiting planting, or for bonsai. Shallow bonsai pots lose moisture fast under California sun, so look at them daily through summer. For a young tree in a deep nursery can, feel 2 to 3 inches into the mix every few days. Water until it streams from the drainage holes, then tip out the saucer. Choose a potting mix that is not alkaline. With bare branches in winter, the tree drinks little, so allow a bit more drying between waterings, but never let the mix go fully dry.

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

Chinese Sweet Gum: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.370.40.780.78––
Feb0.530.650.810.87––
Mar0.871.091.151.3––
Apr1.181.521.41.61––
May1.462.081.611.95––
Jun1.612.481.742.29––
Jul1.612.671.982.51––
Aug1.492.391.862.33––
Sep1.241.81.491.86––
Oct0.871.181.151.33––
Nov0.470.560.840.9––
Dec0.310.340.650.68––
Year1217.1115.518.41––

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 Chinese sweet gum. 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 Chinese sweet gum 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 Chinese sweet gum, 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 Chinese sweet gum in summer?

In July, established Chinese sweet gum in loam needs a deep watering about every 8 days in the Central Valley, about every 11 days on the south coast 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 Chinese sweet gum need per day?

In July in the Central Valley, established Chinese sweet gum 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 Chinese sweet gum change across California?

Yes. WUCOLS rates Chinese sweet gum separately for each of the six California climate zones: moderate water in the North-Central Coastal zone, moderate water in the Central Valley zone, moderate water in the South Coastal zone, moderate water 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.

Are Chinese sweet gum balls a problem?

They hang on the tree through winter and fall from about December to April, so plan to rake paths. They are softer and less woody than the balls of the American sweet gum. That makes them less of an ankle hazard underfoot.

Why are my Chinese sweet gum leaves turning yellow in summer?

Alkaline soil is a common cause, since this tree develops iron chlorosis there. Extra water will not green it up. Check the soil and water drainage before adding more irrigation.

Will Chinese sweet gum roots lift a sidewalk?

They can, which limits its use as a street tree. Plant it in a large area with room to grow, such as a lawn or park. A planting strip should be more than 6 feet wide.

Does Chinese sweet gum have fall color?

Some trees turn showy red or yellow, while others stay a dull green. The color varies from tree to tree. Named selections such as 'Afterglow' are chosen for rosy red and orange fall leaves.

When should I prune a Chinese sweet gum?

Prune in late winter or early spring. Train a young tree to a strong central leader. Remove dead or damaged branches and thin crowded ones to improve air flow.

Can Chinese sweet gum grow in shade?

No. It is intolerant of shade and needs full sun. Choose a spot with 6 or more hours of direct sun a day.

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Sources