WateringTimesWatering plan, $19
Hypericum calycinum, WUCOLS IV

How often to water Aaron's beard in California

In July in the Central Valley, established Aaron's beard in loam needs a deep watering about every 8 days: about 8.8 gallons each time for a plant 4 feet across, about 7.6 gallons a week. Aaron's beard is a low, spreading St. John's wort that runs by underground stems into a dense groundcover, excellent for slopes and sandy soils. Large yellow summer flowers with a puff of stamens sit above oblong leaves. It grows in sun or deep shade, stays evergreen in mild winters, and is vigorous enough to swamp small plants nearby.

Ground coverShrubRated for 4 of 6 zones

How often to water Aaron's beard, 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 Aaron's beard 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

  • Ground dry 3 inches below the surface under the mat in summer tells you Aaron's beard wants a soak
  • Leaves drooping and losing their sheen in afternoon heat can indicate thirst
  • Patches browning on a sunny slope during a hot spell can follow a dry root zone
  • Rust-colored spots or leaf blotches in damp shade point to a fungal problem rather than water

How to water it

  • Run in-line drip or a soaker across the planting so the whole mat gets water
  • Wet the soil 6 to 8 inches deep, and wait for the top couple of inches to dry before repeating
  • Plant in any well-drained but moisture-retentive soil, from sand to heavy clay
  • Use it on slopes and under trees, where its runners hold soil
  • Shear or mow it to the ground in early spring to renew the mat

Through the seasons

Water a new planting regularly until runners spread and the mat closes in. Established plantings have moderate drought tolerance but look best with deep summer soaks. It stays evergreen in mild winters and dies to the ground in cold ones, then returns in spring and flowers in summer on new growth. WUCOLS rates Aaron's beard moderate water on the north-central coast, in the Central Valley, on the south coast and in South Inland. WUCOLS marks it as not suited to the low desert, and has not evaluated it for the high desert.

In pots

Aaron's beard can spill from a large planter or raised bed, which keeps its runners contained. Use a well-drained mix that holds some moisture. When the top two inches feel dry, pour until water leaves the holes. In summer, a sunny planter can dry within a few days. Do not let water stand in the saucer. Cut it back hard in early spring. In winter, water only when the mix dries.

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

Aaron's Beard: 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 Aaron's beard. Plants that drink alike can share one valve and one schedule.

RosesRosa hybrids..bushmoderate water, Central Valley2.67 gal/sq ft in JulyAzaleasRhododendron spp. (CA native and non-native spp.)moderate water, Central Valley2.67 gal/sq ft in JulyCamelliasCamellia japonica (SHADE IN DESERT)moderate water, Central Valley2.67 gal/sq ft in JulyGardeniasGardenia spp. & cvs.moderate water, Central Valley2.67 gal/sq ft in JulyBird of ParadiseStrelitzia reginae (shade in desert)moderate water, Central Valley2.67 gal/sq ft in JulyHibiscusHibiscus rosa-sinensismoderate water, Central Valley2.67 gal/sq ft in JulySago PalmCycas revolutamoderate water, Central Valley2.67 gal/sq ft in JulyStar 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 JulyArborvitaeThuja occidentalis ssp. & cvs.moderate water, Central Valley2.67 gal/sq ft in JulyBambooBambusa spp.moderate water, Central Valley2.67 gal/sq ft in JulyLilacsSyringa hybrids (including Descanso hybrids)moderate water, Central Valley2.67 gal/sq ft in JulySpireaSpiraea spp. (CA native and non native spp.)moderate water, Central Valley2.67 gal/sq ft in JulyButterfly BushBuddleja davidii and hybridsmoderate 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 July

Similar plants that need less water 16

Rated lower than Aaron's beard in the Central Valley. Worth a look for a new bed or a lawn replacement.

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 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 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 July
Minutes for your sprinklers

Turn this into minutes on your water days

Every city page has a calculator that takes Aaron's beard, 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 Aaron's beard in summer?

In July, established Aaron's beard 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 Aaron's beard need per day?

In July in the Central Valley, established Aaron's beard needs about 1.1 gallons a day for a plant 4 feet across and about 4.3 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 Aaron's beard change across California?

Yes. WUCOLS rates Aaron's beard 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 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.

Is Aaron's beard invasive?

It spreads vigorously by underground stems and can swamp small plants. Edge it or plant it where spreading is welcome. Slopes and tree bases suit it.

Can Aaron's beard grow in dry shade?

Yes, it grows in heavy shade under trees and in dry shade. It flowers best with some sun. Water deeply in long dry spells.

Should I cut back Aaron's beard?

Cut it to the ground in early spring to refresh the groundcover. It blooms on new growth, so flowering continues. Water as new shoots appear.

Is Aaron's beard poisonous?

It carries a high severity poison rating. Keep pets and livestock from grazing it. Wear gloves when cutting it back.

Does Aaron's beard stay green in winter?

It is evergreen in warm winter climates and may die back in cold ones. It returns each spring. Water lightly through winter.

More plant watering guides

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Sources