WateringTimesWatering plan, $19
Pachysandra terminalis, WUCOLS IV

How often to water Japanese spurge in California

In July in the Central Valley, established Japanese spurge in loam needs a deep watering about every 8 days: about 2.2 gallons each time for a plant 2 feet across, about 1.9 gallons a week. Japanese spurge, or pachysandra, is an evergreen groundcover from Japan and north-central China that grows 6 to 12 inches high and spreads by rhizomes into large colonies. It thrives in the dappled shade of big trees and bleaches in full sun or high wind. It prefers moist, slightly acidic soil rich in organic matter, and it helps hold soil on shady slopes.

Ground coverRated for 3 of 6 zones

How often to water Japanese spurge, month by month

Your city
Plant width
2 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 Japanese spurge 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 2 inches down under the leaves in summer means Japanese spurge needs water
  • Leaves turning pale or bleached point to too much sun or wind, not thirst
  • Leaves wilting by afternoon in dry soil can indicate thirst
  • Brown blotches spreading through a crowded bed point to leaf blight, worsened by overhead water

How to water it

  • Water at the soil with drip or a soaker, not overhead
  • Keep the soil evenly moist, wetting it 6 inches deep
  • Plant in part to full shade in moist, slightly acidic, organic soil
  • Space new plants 6 to 12 inches apart
  • Thin crowded beds to improve air flow

Through the seasons

Water new plantings regularly, since a groundcover takes about three years to fill in. Established beds want moderate, steady moisture, especially under thirsty trees. It blooms in early spring and stays evergreen. Avoid overhead watering, which helps leaf blight spread. WUCOLS rates Japanese spurge moderate water on the north-central coast, in the Central Valley and on the south coast. WUCOLS marks it as not suited to South Inland, the high desert or the low desert.

In pots

Japanese spurge can grow in a wide, shallow container in a shady spot, where its glossy whorls of leaves stay neat. Use a moist, slightly acidic, well-drained mix. Water when the top inch dries, until it drains. In summer, check pots every couple of days. Water the soil, not the leaves. Empty the saucer. In winter, water when the mix dries between rains.

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

Japanese Spurge: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.370.40.78–––
Feb0.530.650.81–––
Mar0.871.091.15–––
Apr1.181.521.4–––
May1.462.081.61–––
Jun1.612.481.74–––
Jul1.612.671.98–––
Aug1.492.391.86–––
Sep1.241.81.49–––
Oct0.871.181.15–––
Nov0.470.560.84–––
Dec0.310.340.65–––
Year1217.1115.5–––

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 Japanese spurge. Plants that drink alike can share one valve and one schedule.

Star JasmineTrachelospermum jasminoides and cvs.moderate water, Central Valley2.67 gal/sq ft in JulyHoneysuckleLonicera japonicamoderate water, Central Valley2.67 gal/sq ft in JulyIvyHedera helixmoderate water, Central Valley2.67 gal/sq ft in JulyStrawberriesFragaria spp. & cvs. (CA native and non-natives species)moderate water, Central Valley2.67 gal/sq ft in JulyCarpet BugleAjuga reptans (shade)moderate water, Central Valley2.67 gal/sq ft in JulyGreen Supreme ManzanitaArctostaphylos uva-ursi 'Green Supreme'moderate water, Central Valley2.67 gal/sq ft in JulyMassachusetts ManzanitaArctostaphylos uva-ursi 'Massachusetts'moderate water, Central Valley2.67 gal/sq ft in JulySerbian BellflowerCampanula poscharskyanamoderate water, Central Valley2.67 gal/sq ft in JulyBunchberryCornus canadensismoderate water, Central Valley2.67 gal/sq ft in JulyKenilworth IvyCymbalaria muralismoderate water, Central Valley2.67 gal/sq ft in JulyCranesbillGeranium spp.moderate water, Central Valley2.67 gal/sq ft in JulyGreen CarpetHerniaria glabramoderate water, Central Valley2.67 gal/sq ft in JulySpotted DeadnettleLamium maculatummoderate water, Central Valley2.67 gal/sq ft in JulyLemon BalmMelissa officinalismoderate water, Central Valley2.67 gal/sq ft in JulyMoss PinkPhlox subulatamoderate water, Central Valley2.67 gal/sq ft in JulySpring CinquefoilPotentilla neumannianamoderate water, Central Valley2.67 gal/sq ft in July

Similar plants that need less water 16

Rated lower than Japanese spurge in the Central Valley. Worth a look for a new bed or a lawn replacement.

BougainvilleaBougainvillea & spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyLantanaLantana camara ssp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyJunipersJuniperus spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyYarrowAchillea millefolium (non-native hybrids)low water, Central Valley1.07 gal/sq ft in JulySagebrushArtemisia spp. (shrubby)low water, Central Valley1.07 gal/sq ft in JulyCalifornia Native YarrowAchillea millefolium (CA native cultivars)low water, Central Valley1.07 gal/sq ft in JulyWoolly YarrowAchillea tomentosalow water, Central Valley1.07 gal/sq ft in JulyGround Morning GloryConvolvulus mauritanicuslow water, Central Valley1.07 gal/sq ft in JulyRock CotoneasterCotoneaster horizontalislow water, Central Valley1.07 gal/sq ft in JulySouth African GeraniumPelargonium sidoideslow water, Central Valley1.07 gal/sq ft in JulyLippia GroundcoverPhyla nodiflora (Lippia nodiflora) cvs.low water, Central Valley1.07 gal/sq ft in JulyRock SoapwortSaponaria ocymoideslow water, Central Valley1.07 gal/sq ft in JulyMother of ThymeThymus praecoxlow water, Central Valley1.07 gal/sq ft in JulyVancouver Jade BearberryArctostaphylos uva-ursi 'Vancouver Jade'low water, Central Valley1.07 gal/sq ft in JulyTrailing LantanaLantana montevidensis (sellowiana) ssp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyGermanderTeucrium chamaedrys ssp. & cvs.low 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 Japanese spurge, 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 Japanese spurge in summer?

In July, established Japanese spurge in loam needs a deep watering about every 8 days in the Central Valley and about every 11 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 Japanese spurge need per day?

In July in the Central Valley, established Japanese spurge needs about 0.3 gallons a day for a plant 2 feet across and about 1.1 gallons a day for a plant 4 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 Japanese spurge change across California?

Yes. WUCOLS rates Japanese spurge 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, not suited to this region 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.

Can Japanese spurge grow in sun?

No, it is intolerant of full sun, and its leaves bleach in sun or high wind. Plant it in part to full shade. Dappled shade under trees is ideal.

How fast does Japanese spurge spread?

It spreads by rhizomes and takes about three years to fill in when spaced 6 to 12 inches apart. It forms large colonies. It can be hard to remove.

What causes brown patches in pachysandra?

Leaf blight is a common problem. Thin crowded plants and avoid overhead watering. Remove damaged plants.

Is Japanese spurge good for slopes?

Yes, it helps control erosion on shady slopes and banks. Water with drip on slopes. Mulch until it fills in.

What pests bother Japanese spurge?

Euonymus scale can attack it. Root rot follows soggy soil. Check plants regularly.

More plant watering guides

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Sources