WateringTimesWatering plan, $19
Nandina domestica and cvs., WUCOLS IV

How often to water heavenly bamboo in California

In July in the Central Valley, established heavenly bamboo in loam needs a deep watering about every 20 days: about 8.8 gallons each time for a plant 4 feet across, about 3.0 gallons a week. Heavenly bamboo is an upright evergreen shrub from China and Japan with cane-like stems and lacy, divided leaves that open reddish. Sprays of tiny white flowers in late spring turn into bright red berries that last through winter. It is adaptable to sun or part shade and many soils, but it spreads by rhizomes and seed, and all parts are toxic.

ShrubRated for 6 of 6 zones

How often to water heavenly bamboo, 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 heavenly bamboo 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

  • Soil dry 3 inches down at the base of the canes in summer signals heavenly bamboo needs water
  • Leaflets dropping and canes looking sparse after a dry spell can indicate thirst
  • Leaves dulling and curling in a hot spell can follow a dry root zone
  • Yellow leaves with soggy soil at the base suggest poor drainage

How to water it

  • Water the root zone around the cane clump with drip or a soaker
  • Soak about 8 inches down, then let the top few inches dry
  • Plant in sun to part shade in well-drained soil
  • Prune to shape, keeping in mind that flowers and fruit come on new growth
  • Choose fruitless forms or remove berries to protect birds and stop seedlings

Through the seasons

Water a new plant regularly through its first summer as it settles. Established clumps are adaptable and take some dryness, with deeper soaks in hot weather. It spreads slowly from the base by rhizomes. It is evergreen, with red new growth, fall leaf color in many forms, and berries through winter. On the north-central coast and in the Central Valley, WUCOLS rates heavenly bamboo low water. The south coast, South Inland, the high desert and the low desert carry a moderate water rating.

In pots

Heavenly bamboo grows well in containers, and compact forms suit smaller pots. Use a well-drained mix and water when the top couple of inches dry, letting it drain. In summer heat, check every few days. Empty the saucer each time. Cut berry clusters before birds eat them. In winter, rain may be enough, so feel the mix before watering. Repot every few years in spring.

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
0.761.52.33.00.16JAN0.26FEB0.43MAR0.61APR0.83MAY0.99JUN1.07JUL0.95AUG0.72SEP0.47OCT0.22NOV0.14DEC0.761.52.33.00.16JFM0.61AMJ1.07JAS0.47OND
Gallons per square foot per month, Central Valley. Peak 1.07 in Jul, 6.84 a year.

Monthly water need by climate zone

Heavenly Bamboo: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.150.160.780.780.740.78
Feb0.210.260.810.870.930.93
Mar0.350.431.151.31.461.52
Apr0.470.611.41.611.891.95
May0.580.831.611.952.392.45
Jun0.640.991.742.292.852.79
Jul0.641.071.982.513.042.85
Aug0.60.951.862.332.792.6
Sep0.50.721.491.862.142.08
Oct0.350.471.151.331.461.49
Nov0.190.220.840.90.930.96
Dec0.120.140.650.680.650.68
Year4.86.8415.518.4121.2721.08

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 heavenly bamboo. Plants that drink alike can share one valve and one schedule.

LavenderLavandula spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyRosemaryRosmarinus officinalislow water, Central Valley1.07 gal/sq ft in JulyBougainvilleaBougainvillea & spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyOlive TreesOlea europaea 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 JulyLantanaLantana camara ssp. & cvs.low water, Central Valley1.07 gal/sq ft in JulySalviaSalvia greggii ssp., cvs. & hybridslow water, Central Valley1.07 gal/sq ft in JulyAloeAloe spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulySucculentsEcheveria spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyJunipersJuniperus spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyRussian SagePerovskia spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulySagebrushArtemisia spp. (shrubby)low water, Central Valley1.07 gal/sq ft in JulyWild PrivetLigustrum vulgarelow water, Central Valley1.07 gal/sq ft in JulyCoralberrySymphoricarpos orbiculatus (SHADE)low water, Central Valley1.07 gal/sq ft in JulySydney Golden WattleAcacia longifolialow water, Central Valley1.07 gal/sq ft in JulyBlue Leaf WattleAcacia salignalow 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 heavenly bamboo, 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 heavenly bamboo in summer?

In July, established heavenly bamboo in loam needs a deep watering about every 20 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 heavenly bamboo need per day?

In July in the Central Valley, established heavenly bamboo needs about 0.4 gallons a day for a plant 4 feet across and about 1.7 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 heavenly bamboo change across California?

Yes. WUCOLS rates heavenly bamboo separately for each of the six California climate zones: low water in the North-Central Coastal zone, low water in the Central Valley zone, moderate water in the South Coastal zone, moderate water in the South Inland zone, moderate water in the High and Intermediate Desert zone, moderate water in the Low Desert zone. The monthly table above shows how the same rating translates into different gallon amounts as reference evapotranspiration changes.

Are heavenly bamboo berries poisonous?

Yes, all parts contain cyanide compounds that can harm people, pets and livestock. Cedar waxwings have died from eating too many berries. Choose fruitless cultivars or remove berries.

Is heavenly bamboo invasive?

It self-sows and spreads by rhizomes, and it is invasive in parts of the Southeast. Remove berries to reduce seedlings. Pull young plants promptly.

Is heavenly bamboo a real bamboo?

No, it is in the barberry family and only looks bamboo-like. Its canes rise from the base. It does not run like true bamboo.

How should I prune heavenly bamboo?

Prune it to keep the shape you want. Next season's flowers and fruit appear on new growth. Water as usual after pruning.

Why are my heavenly bamboo leaves red?

New growth is reddish, and many forms turn red in fall or winter. Color varies from year to year. It is not a water problem.

More plant watering guides

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Sources