WateringTimesWatering plan, $19
Oxalis oregana (shade), WUCOLS IV

How often to water redwood sorrel in California

In July in the Central Valley, established redwood sorrel in loam needs a deep watering about every 3 days: about 1.5 gallons each time for a plant 2 feet across, about 3.0 gallons a week. Redwood sorrel is a California native that carpets the shady floor of redwood and Douglas fir forests with clover-like leaves. It creeps by rhizomes and bears white, pink or lilac flowers from spring. Give it shade and moist, humus-rich soil, and watch the leaflets: they fold when heat, sun or drought press it.

PerennialCalifornia nativeRated for 3 of 6 zones

How often to water redwood sorrel, 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 redwood sorrel 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

  • Leaflets folded shut in full shade, with the top inch of soil dry, mean the patch needs water
  • Leaflets that fold only where sun reaches them point to too much light, not dry soil
  • Leaves dropping across the patch in a hot, dry spell show severe stress that calls for a soak and more shade
  • Leaflets folding during rain is a normal response and not a sign of trouble
  • New shoots popping up well past the bed show it is getting more water than it needs, since moist soil fuels its spread

How to water it

  • Water the whole patch evenly with a soaker hose or a gentle shower, wetting the soil several inches down
  • Keep the soil moist but never waterlogged, letting only the surface dry before the next watering
  • Plant in full or part shade in fertile, humus-rich soil, such as under trees or on the north side of a building
  • Spread leaf litter or fine compost over the bed to keep the soil cool and moist
  • Water less at the edges where you want the patch to stop spreading

Through the seasons

Keep a new planting evenly moist until the rhizomes root into the bed. Established patches still want moist soil through the dry season, though cutting back water reins in their spread. Blooms begin in spring, and the leaves fold in hot sun or drought and may drop if stress is severe. Winter rain usually keeps the bed moist on the coast and in the Central Valley. The WUCOLS ratings here assume a shady site. On the north-central coast, where it grows wild under redwoods, WUCOLS rates it moderate water. It rates high water in the Central Valley and on the south coast. WUCOLS marks it as not suited to South Inland and has not evaluated it for the high desert or the low desert.

In pots

Redwood sorrel suits a container on a shady patio, where its creeping rhizomes soon fill the pot. Use a wide pot with drainage holes and a rich, humus-heavy mix. In summer, check the top inch every couple of days, and daily during inland heat, then water when it feels dry. Water until it runs from the holes and empty the saucer. Keep the pot in shade, since direct sun makes the leaves fold. In winter, let rain help and water only when the top of the mix dries.

1 Your climate zone six WUCOLS zones, each from its own reference city
4.27gal per sq ft in JulyHigh water use in the Central Valley zone
A year
27.38 gal per sq ft
Reference
Sacramento climate table
Counts
Plant need, before sprinkler losses
1.12.13.24.30.64JAN1.04FEB1.74MAR2.43APR3.32MAY3.97JUN4.27JUL3.82AUG2.88SEP1.88OCT0.89NOV0.55DEC1.12.13.24.30.64JFM2.43AMJ4.27JAS1.88OND
Gallons per square foot per month, Central Valley. Peak 4.27 in Jul, 27.38 a year.

Monthly water need by climate zone

Redwood Sorrel: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.370.641.24–––
Feb0.531.041.29–––
Mar0.871.741.84–––
Apr1.182.432.23–––
May1.463.322.58–––
Jun1.613.972.78–––
Jul1.614.273.17–––
Aug1.493.822.98–––
Sep1.242.882.38–––
Oct0.871.881.84–––
Nov0.470.891.34–––
Dec0.310.551.04–––
Year1227.3824.8–––

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 high water in the Central Valley, like redwood sorrel. Plants that drink alike can share one valve and one schedule.

Japanese Sweet FlagAcorus gramineushigh water, Central Valley4.27 gal/sq ft in JulyRed GingerAlpinia purpuratahigh water, Central Valley4.27 gal/sq ft in JulyShell GingerAlpinia zerumbethigh water, Central Valley4.27 gal/sq ft in JulySiberian BuglossBrunnera macrophyllahigh water, Central Valley4.27 gal/sq ft in JulyMarsh MarigoldCaltha palustrishigh water, Central Valley4.27 gal/sq ft in JulyUmbrella Sedge and PapyrusCyperus spp. (CA native and non-native species)high water, Central Valley4.27 gal/sq ft in JulyUmbrella PlantDarmera peltata (Peltiphyllum)high water, Central Valley4.27 gal/sq ft in JulyFoxgloveDigitalis purpurea cvshigh water, Central Valley4.27 gal/sq ft in JulyLeopard PlantFarfugium japonicum cvs. (Ligularia tussilaginea cvs.)high water, Central Valley4.27 gal/sq ft in JulyTransvaal DaisyGerbera jamesonii & hybridshigh water, Central Valley4.27 gal/sq ft in JulyGiant GunneraGunnera manicatahigh water, Central Valley4.27 gal/sq ft in JulyWhite Ginger LilyHedychium coronariumhigh water, Central Valley4.27 gal/sq ft in JulyJapanese IrisIris ensatahigh water, Central Valley4.27 gal/sq ft in JulyRushJuncus aquatic spp. (native and non-native spp.)high water, Central Valley4.27 gal/sq ft in JulyCardinal FlowerLobelia cardinalis hybrids and cvs. (CA native and non-native spp.)high water, Central Valley4.27 gal/sq ft in JulyBananaMusa spp. (shade in low desert)high water, Central Valley4.27 gal/sq ft in July

Similar plants that need less water 16

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

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
Minutes for your sprinklers

Turn this into minutes on your water days

Every city page has a calculator that takes redwood sorrel, 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 redwood sorrel in summer?

In July, established redwood sorrel in loam needs a deep watering about every 3 days in the Central Valley and about every 5 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 redwood sorrel need per day?

In July in the Central Valley, established redwood sorrel needs about 0.4 gallons a day for a plant 2 feet across and about 1.7 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 redwood sorrel change across California?

Yes. WUCOLS rates redwood sorrel separately for each of the six California climate zones: moderate water in the North-Central Coastal zone, high water in the Central Valley zone, high water in the South Coastal zone, not suited to this region 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.

Why do redwood sorrel leaves fold up?

The leaflets fold in response to high heat, sun, drought and even rain. In severe conditions the leaves may drop. Folding in deep shade on a dry day is the cue to check the soil.

Will redwood sorrel grow under a redwood tree?

Yes. It is one of the few plants that can compete with the shallow roots of redwoods. Those roots draw water too, so check the soil under the canopy through the dry months.

Is redwood sorrel invasive?

It is a native, but it creeps by rhizomes and can take over moist, shady beds. Watering less at the margins slows it. In drier ground it stays small.

Can redwood sorrel grow in sun?

It does best in full or part shade. Direct sun folds the leaves, and away from cool, shady woods it is not very drought tolerant. The WUCOLS ratings for it assume shade.

When does redwood sorrel flower?

Flowering starts in spring and can carry on into fall. The flowers are white, pink or lilac and about an inch across. Moths and butterflies visit them.

How do I divide redwood sorrel?

Divide clumps in spring, lifting pieces of rhizome with leaves attached. Replant them at once and keep them moist until new growth shows.

More plant watering guides

Weeping WillowPeking WillowWillowSteviaDelphiniumCoast RedwoodVariegated Sweet FlagChameleon Houttuynia

Sources