WateringTimesWatering plan, $19
Aconitum napellus, WUCOLS IV

How often to water garden monkshood in California

In July in the Central Valley, established garden monkshood 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. Garden monkshood is a tall, upright perennial with dense spikes of hooded blue purple flowers in summer. It prefers soil that stays reliably moist and cool, never drying out for long between waterings. All of its tissue carries potent toxins, so handle, divide or cut it back only with gloves on.

PerennialRated for 2 of 6 zones

How often to water garden monkshood, 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 garden monkshood 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 beside the clump signals it needs water during the growing season
  • Leaves wilting or drooping in afternoon heat over dry soil can indicate thirst
  • Poorly opening monkshood flowers warrant checking soil moisture and exposure before changing irrigation
  • Saturated ground around a declining clump calls for a drainage check, since monkshood needs moisture without waterlogging
  • Weak monkshood growth in hot weather warrants reviewing the site, since this plant grows best with cool nights

How to water it

  • Water at the base of the clump with drip or a slow hose rather than wetting the flower spikes overhead
  • Keep the top several inches of soil evenly moist through spring growth and summer bloom
  • Choose a site with afternoon shade in warmer gardens to help the soil hold moisture longer
  • Work compost into the bed to improve moisture retention, especially in fast draining soil
  • Wear gloves whenever you handle, divide or cut back this plant, including while adjusting mulch or drip lines nearby

Through the seasons

Keep a newly planted garden monkshood consistently moist through its first season while the roots settle in. This deciduous perennial loses its foliage for winter, so fading flowers alone are not a reason to stop soil checks. Divisions can be slow to reestablish, so keep separated pieces evenly moist and undisturbed afterward. On the north-central coast and in the Central Valley, let winter rain replace irrigation when the soil remains moist. WUCOLS rates it moderate water on the north-central coast and in the Central Valley. WUCOLS marks the south coast, South Inland, the high desert and the low desert as not suited to it.

In pots

If keeping garden monkshood in a container, use a rich mix that holds moisture while allowing excess water to drain. Check the top inch or two often during California summer heat, since a pot dries faster than an open bed. Water until it drains through the holes, then empty the saucer so the roots do not sit wet for long. Choose afternoon shade and reduce watering when winter rain keeps the mix moist. Always wear gloves when repotting or dividing, since all parts remain toxic even in a container.

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

Garden Monkshood: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.370.4––––
Feb0.530.65––––
Mar0.871.09––––
Apr1.181.52––––
May1.462.08––––
Jun1.612.48––––
Jul1.612.67––––
Aug1.492.39––––
Sep1.241.8––––
Oct0.871.18––––
Nov0.470.56––––
Dec0.310.34––––
Year1217.11––––

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 garden monkshood. 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 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 JulyEnglish DaisyBellis perennismoderate water, Central Valley2.67 gal/sq ft in July

Similar plants that need less water 16

Rated lower than garden monkshood 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 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 JulyMountain Lady's MantleAlchemilla alpinalow 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 garden monkshood, 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 much water does garden monkshood need per day?

In July in the Central Valley, established garden monkshood 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 garden monkshood change across California?

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

Is garden monkshood safe to grow around children or pets?

Every part of garden monkshood is highly poisonous if eaten, and skin contact should be avoided. Plant it away from areas where children or pets play or forage. Wear gloves when handling it and wash your hands afterward.

Why is my garden monkshood wilting in a shaded bed?

It needs moisture even in partial shade, but wilt alone does not identify the cause. Check the surrounding soil and water only if it is drying. Persistent wilting in moist soil warrants inspection for drainage problems or disease.

Can I divide garden monkshood like other perennials?

Yes, but divisions can be slow to settle in and are best left undisturbed once established. Always wear gloves during division because the roots are especially toxic. Keep new divisions evenly moist while they reroot.

Does garden monkshood need staking?

Tall stems may need support, especially where the plant is exposed. This is separate from watering and does not change how deep you should check the soil. Position a support carefully beside the clump rather than pushing it through the crown.

Why aren't my garden monkshood flowers opening fully?

Check moisture and exposure, since this species needs cool conditions and soil that stays moist. Do not assume extra watering will solve unopened flowers when the ground is already wet. Inspect the developing spikes for damage and address drainage before adding more water.

More plant watering guides

Katsura TreeEastern RedbudChinese RedbudJudas TreeNight JessamineChilean JessamineEvergreen ClematisBushy Clematis

Sources