WateringTimesWatering plan, $19
Yucca glauca, WUCOLS IV

How often to water soapweed yucca in California

In July on the north-central coast, established soapweed yucca in loam needs a deep soak only about once a month or less: about 8.8 gallons each time for a plant 4 feet across. Soapweed yucca is a Great Plains native that forms rosettes of long, narrow, sharp-tipped, grayish green leaves edged in white. In early summer a stalk carries hanging, bell-shaped, greenish white flowers. It is one of the most cold-hardy yuccas, thrives on poor, rocky soil in full sun, and cannot survive in waterlogged ground.

ShrubSucculentRated for 3 of 6 zones

How often to water soapweed yucca, 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 soapweed yucca 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 4 inches down beside a young rosette in its first summer signals soapweed yucca can take a soak
  • Rosette leaves folding inward and looking dull after a very long dry spell can indicate thirst
  • Leaves yellowing from the center and a soft base over wet soil point to rot
  • Rosettes collapsing after a wet winter in heavy soil suggest poor drainage

How to water it

  • Water a new plant at the base with a slow hose, then mostly stop
  • Soak deeply, then let the soil dry completely before any repeat
  • Plant in full sun in sharp-draining, rocky or sandy soil
  • Keep it far from lawns and other irrigated beds
  • Leave room for offsets that slowly form a colony

Through the seasons

Water a new soapweed yucca a few times through its first summer, then let rain carry it. Established plants need little or no irrigation. It is evergreen and flowers in early summer. It is among the most cold-hardy yuccas, so frost is rarely a problem. WUCOLS rates soapweed yucca very low water on the north-central coast. On the south coast and in the high desert it carries a low water rating. WUCOLS has not evaluated it for the Central Valley, South Inland or the low desert.

In pots

Soapweed yucca suits a heavy pot of gritty, fast-draining mix in full sun. Water only when the mix is dry several inches down, then let it drain completely. In summer, a pot may need water every week or two. Never leave water in the saucer. In winter, water very rarely. Wear gloves and eye protection near the sharp leaf tips. Repot only when offsets crowd the rim, since roots like to be left alone.

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

WUCOLS lists Soapweed Yucca as not evaluated for the Central Valley zone, so no monthly figure is computed here.

Monthly water need by climate zone

Soapweed Yucca: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.04–0.31–0.3–
Feb0.05–0.32–0.37–
Mar0.09–0.46–0.58–
Apr0.12–0.56–0.76–
May0.15–0.64–0.95–
Jun0.16–0.69–1.14–
Jul0.16–0.79–1.22–
Aug0.15–0.74–1.12–
Sep0.12–0.6–0.86–
Oct0.09–0.46–0.58–
Nov0.05–0.33–0.37–
Dec0.03–0.26–0.26–
Year1.2–6.2–8.51–

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 evaluated in the Central Valley, like soapweed yucca. Plants that drink alike can share one valve and one schedule.

Formosa Sugar PalmArenga englerinot rated, Central Valleyno Central Valley ratingChilean Feather BambooChusquea culeou (C. breviglumis)not rated, Central Valleyno Central Valley ratingBlackbrushColeogyne ramosissimanot rated, Central Valleyno Central Valley ratingGlaucous Scorpion VetchCoronilla valentina glaucanot rated, Central Valleyno Central Valley ratingWillowleaf CotoneasterCotoneaster salicifoliusnot rated, Central Valleyno Central Valley ratingMadagascar SagoCycas thouarsii (SHADE)not rated, Central Valleyno Central Valley ratingIrish HeathDaboecia cantabricanot rated, Central Valleyno Central Valley ratingButterfly PalmDypsis lutescens (Areca)not rated, Central Valleyno Central Valley ratingPurple SpurgeEuphorbia dulcisnot rated, Central Valleyno Central Valley ratingUmbrella BambooFargesia murielaenot rated, Central Valleyno Central Valley ratingBlue Fountain BambooFargesia nitida (Sinarundinaria nitida) (BAMBOO)not rated, Central Valleyno Central Valley ratingPrickly HeathGaultheria mucronata (Pernettya mucronata)not rated, Central Valleyno Central Valley ratingOtterbossieGossypium harknessiinot rated, Central Valleyno Central Valley ratingBox-leaved HollyIlex crenatanot rated, Central Valleyno Central Valley ratingBellyache BushJatropha gossypiifolianot rated, Central Valleyno Central Valley ratingMountain LaurelKalmia latifolianot 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 soapweed yucca, 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 soapweed yucca need per day?

In July on the north-central coast, established soapweed yucca needs about 0.1 gallons a day for a plant 4 feet across and about 0.3 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 soapweed yucca change across California?

Yes. WUCOLS rates soapweed yucca separately for each of the six California climate zones: very low water in the North-Central Coastal zone, not evaluated in the Central Valley zone, low water in the South Coastal zone, not evaluated in the South Inland zone, low water 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.

Where is soapweed yucca native?

It is native to the Great Plains, from Canada to Texas. It grows wild in short grass prairies and desert grasslands. That background explains its love of dry, rocky soil.

Is soapweed yucca cold hardy?

Few yuccas handle cold as well as this one, so frost rarely harms it. Wet winter soil is a bigger risk than cold. Plant it where water drains fast.

Does soapweed yucca spread?

It can offset and slowly form a large colony. Offsets can be dug and replanted. Give it room.

Do the flowers attract wildlife?

Yes, the flowers attract butterflies, and it hosts the yucca moth. The hanging blooms appear in early summer. Water does not need to change.

How do I propagate soapweed yucca?

Divide offsets, take stem cuttings or sow seed after a winter cold treatment. Plant pieces in gritty soil. Water lightly until rooted.

More plant watering guides

Seven Sons TreeGibraltar CandytuftBox-leaved HollyPrivet-Leaved JasmineBellyache BushMountain LaurelBlue Hair GrassChilean Bellflower

Sources