WateringTimesWatering plan, $19
Euphorbia amygdaloides, WUCOLS IV

How often to water wood spurge in California

In July in the Central Valley, established wood spurge in loam needs a deep watering about every 5 days: about 1.5 gallons each time for a plant 2 feet across, about 1.9 gallons a week. Wood spurge is a bushy evergreen perennial with reddish green stems and matte green leaves that darken in winter. Lime-yellow flower clusters top the stems in spring and early summer. It is easy in part or full shade, spreads by rhizomes and needs loose, well-drained soil, since wet winter ground can kill it.

PerennialSucculentRated for 3 of 6 zones

How often to water wood 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 wood 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 foot 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 an inch or two down in summer heat means the clump needs water, even in shade
  • Plants collapsing after a wet winter in heavy soil point to rot from ground that stayed soggy
  • Gray mold on leaves and stems in damp, crowded spots points to botrytis rather than thirst
  • Clusters of aphids on new shoots are a pest problem, not a watering one
  • Clumps opening up and sprawling in deep shade need a little more light, not more water

How to water it

  • Water at the base of the clump, wetting the soil about 6 inches down
  • Let the top inch or two dry between waterings, and water little in winter
  • Plant in loose, well-drained soil in part shade, with afternoon shade where summers run hot
  • Cut flowered stems to the base right after bloom to bring on fresh growth
  • Edge the bed or lift stray runners in spring, since the rhizomes can make it a nuisance

Through the seasons

Water new plants regularly through their first summer. The foliage stays evergreen and darkens in winter, and the flower clusters show from spring into early summer. Cut the spent stems after bloom to make room for new shoots. On the coast and in the Central Valley, winter rain usually covers it, so add no water to cold, wet soil. WUCOLS rates wood spurge moderate water on the north-central coast, in the Central Valley and on the south coast. WUCOLS has not evaluated it for South Inland, the high desert or the low desert.

In pots

Wood spurge can grow in a container in a shady corner, which also keeps its rhizomes in check. Fill a pot that has drainage holes with a loose, quick-draining mix. During hot spells, feel the mix every second day and water when the top inch has dried. Let excess water drain, then empty the saucer. Cut spent flower stems at the base, wearing gloves. In winter, water sparingly, since cold, wet mix can rot it.

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

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

DahliasDahlia spp.moderate water, Central Valley2.67 gal/sq ft in JulyFernsNephrolepis cordifolia (SHADE IN DESERT)moderate water, Central Valley2.67 gal/sq ft in JulyDayliliesHemerocallis spp. & cvs.moderate water, Central Valley2.67 gal/sq ft in JulyBegoniasBegonia & ssp. & cvs. (shade in the desert)moderate water, Central Valley2.67 gal/sq ft in JulyCalla LiliesZantedeschia aethiopica SHADE IN DESERTmoderate water, Central Valley2.67 gal/sq ft in JulySageSalvia officinalis and cvs.moderate water, Central Valley2.67 gal/sq ft in JulyBicolor MonkshoodAconitum cammarummoderate water, Central Valley2.67 gal/sq ft in JulyGarden MonkshoodAconitum napellusmoderate water, Central Valley2.67 gal/sq ft in JulyCarpet BugleAjuga reptans (shade)moderate water, Central Valley2.67 gal/sq ft in JulySnowdrop WindflowerAnemone sylvestrismoderate water, Central Valley2.67 gal/sq ft in JulyMountain SandwortArenaria montanamoderate water, Central Valley2.67 gal/sq ft in JulySwamp MilkweedAsclepias incarnatamoderate water, Central Valley2.67 gal/sq ft in JulyOrange MilkweedAsclepias tuberosamoderate water, Central Valley2.67 gal/sq ft in JulyGreater MasterwortAstrantia majormoderate water, Central Valley2.67 gal/sq ft in JulyHardy BegoniaBegonia grandismoderate water, Central Valley2.67 gal/sq ft in JulyWax BegoniaBegonia semperflorensmoderate water, Central Valley2.67 gal/sq ft in July

Similar plants that need less water 16

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

AgapanthusAgapanthus orientalislow water, Central Valley1.07 gal/sq ft in JulyGeraniumsPelargonium x hortorum and cvs.low water, Central Valley1.07 gal/sq ft in JulySalviaSalvia greggii ssp., cvs. & hybridslow water, Central Valley1.07 gal/sq ft in JulyIrisesIris germanicalow 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 JulyRussian SagePerovskia 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 JulyMountain AlyssumAlyssum montanumlow water, Central Valley1.07 gal/sq ft in JulySilver SageSalvia argentealow water, Central Valley1.07 gal/sq ft in JulyPurple MulleinVerbascum phoeniceumlow water, Central Valley1.07 gal/sq ft in JulySilvery YarrowAchillea clavennaelow water, Central Valley1.07 gal/sq ft in JulyFern Leaf YarrowAchillea filipendulinalow 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 JulyPerennial HollyhockAlcea rosea 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 wood 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 wood spurge in summer?

In July, established wood spurge in loam needs a deep watering about every 5 days in the Central Valley and about every 7 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 wood spurge need per day?

In July in the Central Valley, established wood 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 wood spurge change across California?

Yes. WUCOLS rates wood 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 evaluated 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 wood spurge poisonous?

Yes. The milky sap irritates skin and can damage eyes, and the plant is harmful if eaten by people or pets. Wear gloves and eye protection when cutting it.

Does wood spurge spread?

Yes. It spreads by rhizomes and can become a nuisance if left alone, and it self-seeds unless spent flowers are removed. Mrs. Robb's spurge, a form of this species, spreads even faster and makes a ground cover.

Can wood spurge grow in dry shade?

It copes with part shade, full shade and even dry shade once established. In California summers it still looks best with moderate water. Keep it out of wet, heavy soil.

Should I cut back wood spurge after flowering?

Yes. Remove the flowered stems at the base right after bloom. That encourages fresh growth from the base and stops self-seeding.

Can you overwater wood spurge?

Yes. Overwatering can cause root rot, and soil that stays wet in winter can kill the plant. Let the top of the soil dry between waterings.

More plant watering guides

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Sources