WateringTimesWatering plan, $19
Euphorbia pulcherrima, WUCOLS IV

How often to water poinsettia in California

In July on the south coast, established poinsettia in loam needs a deep watering about every 27 days: about 8.8 gallons each time for a plant 4 feet across, about 2.3 gallons a week. Poinsettia is a frost tender, semitropical shrub grown outdoors only where winters stay mild. Its color show depends on long, uninterrupted fall nights, not on extra watering. Water when the soil surface has dried, and never let the roots sit in soggy soil.

ShrubSucculentRated for 3 of 6 zones

How often to water poinsettia, 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 poinsettia 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 an inch or two down around a poinsettia in active summer growth signals that it needs water
  • Leaves drooping in the heat of the day over dry soil can indicate thirst
  • Bracts fading or dropping early during the fall color period warrant a check of both light and soil moisture
  • Lower leaves yellowing and falling while the soil stays wet can indicate root rot from standing water
  • Black or mushy stem tissue near the soil line warrants an immediate check of drainage, not more watering

How to water it

  • Water poinsettia at the base of the plant, keeping the foliage and bracts dry
  • Soak the root zone until water drains freely, then let the surface dry before watering again
  • Plant poinsettia in soil that drains well, raising the bed where drainage is poor
  • Keep mulch a few inches back from the stems to avoid trapping moisture against them
  • Extend the watered area outward as an outdoor poinsettia grows into a larger shrub

Through the seasons

A young poinsettia needs steady moisture through its first summer as roots establish in the ground. Established plants still prefer even moisture during warm months, then need much less once cooler, shorter days trigger its color change. This shrub is frost tender, and freezing weather can kill it outright, so timing matters as much as habit here. On the south coast, WUCOLS rates poinsettia low water, and in South Inland it rates moderate water. In the low desert, it rates low water, though winter cold there still limits where it survives outdoors. WUCOLS marks it as not suited to the north-central coast, the Central Valley or the high desert, where winter cold works against this tender shrub.

In pots

A potted poinsettia dries out quickly in a warm room or on a sheltered patio. Check the mix with a finger before watering, then soak until water runs from the drainage holes and empty the saucer right away. Never let the pot sit in standing water, since that is the fastest way to lose the roots. In winter, protect any outdoor container from cold nights below 50 degrees, moving it indoors or under cover before frost threatens.

1 Your climate zone six WUCOLS zones, each from its own reference city
Not ratedWUCOLS does not rate Poinsettia for the Central Valley zone
A year
no figure
Reference
Sacramento climate table
Counts
Plant need, before sprinkler losses

WUCOLS lists Poinsettia as not suited to this region for the Central Valley zone, so no monthly figure is computed here.

Monthly water need by climate zone

Poinsettia: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan––0.310.78–0.31
Feb––0.320.87–0.37
Mar––0.461.3–0.61
Apr––0.561.61–0.78
May––0.641.95–0.98
Jun––0.692.29–1.12
Jul––0.792.51–1.14
Aug––0.742.33–1.04
Sep––0.61.86–0.83
Oct––0.461.33–0.6
Nov––0.330.9–0.38
Dec––0.260.68–0.27
Year––6.218.41–8.43

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 not suited to this region in the Central Valley, like poinsettia. Plants that drink alike can share one valve and one schedule.

Chenille PlantAcalypha hispidanot rated, Central Valleyno Central Valley ratingCopperleafAcalypha wilkesiananot rated, Central Valleyno Central Valley ratingYellow Bell BauhiniaBauhinia tomentosanot rated, Central Valleyno Central Valley ratingMagic FlowerCantua buxifolianot rated, Central Valleyno Central Valley ratingClustered Fishtail PalmCaryota mitisnot rated, Central Valleyno Central Valley ratingHawaiian TiCordyline fruticosa (Cordyline terminalis)not rated, Central Valleyno Central Valley ratingFilbertCorylus maximanot rated, Central Valleyno Central Valley ratingWeeping Chinese BanyanFicus benjaminanot rated, Central Valleyno Central Valley ratingRubber PlantFicus elasticanot rated, Central Valleyno Central Valley ratingFranklin TreeFranklinia alatamaha (Gordonia alatamaha)not rated, Central Valleyno Central Valley ratingJungle GeraniumIxora coccineanot rated, Central Valleyno Central Valley ratingOrange JessamineMurraya paniculatanot rated, Central Valleyno Central Valley ratingCommon GuavaPsidium guajavanot rated, Central Valleyno Central Valley ratingOrgan Pipe CactusStenocereus thurberi (Lemaireocereus thurberi)not rated, Central Valleyno Central Valley ratingGiant Bird of ParadiseStrelitzia nicolai (shade in desert)not rated, Central Valleyno Central Valley ratingMarmalade BushStreptosolen jamesoniinot rated, Central Valleyno Central Valley rating
Minutes for your sprinklers

Turn this into minutes on your water days

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

In July, established poinsettia in loam needs a deep watering about every 27 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 poinsettia need per day?

In July on the south coast, established poinsettia needs about 0.3 gallons a day for a plant 4 feet across and about 1.3 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 poinsettia change across California?

Yes. WUCOLS rates poinsettia separately for each of the six California climate zones: not suited to this region in the North-Central Coastal zone, not suited to this region in the Central Valley zone, low water in the South Coastal zone, moderate water in the South Inland zone, not suited to this region in the High and Intermediate Desert zone, low water in the Low Desert zone. The monthly table above shows how the same rating translates into different gallon amounts as reference evapotranspiration changes.

Why did my outdoor poinsettia lose its leaves in winter?

Cold nights below 50 degrees can cause leaf drop and lasting damage. A hard frost can kill the plant outright. Move a container plant under cover before cold nights arrive.

How do I get my poinsettia bracts to turn red again?

Bract color depends on long, unbroken nights in fall, not on watering changes. Even brief light from a porch lamp can interrupt the process. Keep the plant in complete darkness overnight starting in early fall for color to develop.

Can I plant a holiday poinsettia in my yard afterward?

In a mild winter area it can grow into a large outdoor shrub over the years. Choose a spot with well drained soil and some frost protection nearby. Harden it off gradually before moving it from an indoor pot to open ground.

Why is my poinsettia stem turning black at the soil line?

Blackened, soft stem tissue near the ground usually points to a root or stem rot from excess moisture. Check that water drains away completely and stop soaking the base. A plant with this damage may not recover.

Does poinsettia sap need special handling?

Its milky sap can irritate skin and eyes on contact. Wear gloves when pruning and wash any exposed skin promptly. Keep cut stems away from children and pets.

Why do my poinsettia leaves show spots after watering?

Water left sitting on the foliage can encourage leaf spot in humid or crowded conditions. Water at the soil instead of over the leaves. Space plants so air moves freely between them.

More plant watering guides

Hawaiian TiFilbertSpotted GumDove TreeRoyal PoincianaTriangle PalmMountain White GumRainbow Eucalyptus

Sources