WateringTimesWatering plan, $19
Dypsis decaryi, WUCOLS IV

How often to water triangle palm in California

In July on the south coast, established triangle palm in loam needs a deep watering about every 11 days: about 55 gallons each time under a 10 foot canopy, about 35 gallons a week. Triangle palm is a landscape palm that WUCOLS rates only for the south coast and South Inland. Among the palms commonly planted in California, it is rated mostly disease resistant. It is, however, a confirmed California host of the South American palm weevil, an invasive pest of palms, so its crown is worth watching.

TreePalm or cycadRated for 2 of 6 zones

How often to water triangle palm, month by month

Your city
Canopy width
10 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 triangle palm 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 under the branches, 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 canopy width

A tree with its canopy width marked across the widest branches and the circle under it shaded blue

Measure across the branches, from the tips of the outer leaves on one side to the tips on the other. A tape works, or pace it out.

Water the whole circle under the branches, shown in blue. The gallons here cover that circle.

A wider canopy means more gallons each watering, not more waterings. While the tree is young, measure again each spring.

How to tell it needs water

  • Soil dry several inches down around the trunk in summer means triangle palm can take a deep soak
  • Older fronds browning at the tips in a long dry spell suggest the root zone dried
  • Fronds yellowing over soggy ground point to too much water
  • A crown declining while the soil stays moist calls for a pest check rather than more water

How to water it

  • Water deeply around the trunk, then let the top few inches dry
  • Use a wide basin or drip ring so water reaches the whole root zone
  • Plant in a warm, sunny spot with good drainage
  • Remove only dead fronds, leaving green ones in place
  • Look over the crown regularly for pest damage

Through the seasons

Give a newly planted palm regular water through its first summer while roots spread. Established palms want moderate, deep watering through the dry season. Keep watering consistent rather than swinging between soggy and bone dry, since wet soil invites root trouble in palms. Triangle palm gets a moderate water rating from WUCOLS on the south coast and in South Inland. The north-central coast, the Central Valley, the high desert and the low desert are all zones WUCOLS marks it as not suited to.

In pots

Triangle palm can grow in a large, heavy container for years, which suits patios in the warm south. Fill it with a fast-draining mix. Once the upper two inches have dried, water slowly until it runs out the holes. In summer heat, a potted palm may need water every few days. Do not let it sit in a saucer of water. In winter, wait until the mix dries before watering again.

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

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

Monthly water need by climate zone

Triangle Palm: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan––0.780.78––
Feb––0.810.87––
Mar––1.151.3––
Apr––1.41.61––
May––1.611.95––
Jun––1.742.29––
Jul––1.982.51––
Aug––1.862.33––
Sep––1.491.86––
Oct––1.151.33––
Nov––0.840.9––
Dec––0.650.68––
Year––15.518.41––

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

Sugar MapleAcer saccharumnot rated, Central Valleyno Central Valley ratingQueensland KauriAgathis robustanot rated, Central Valleyno Central Valley ratingCherimoyaAnnona cherimolanot rated, Central Valleyno Central Valley ratingPurple Orchid TreeBauhinia variegata (purpurea)not rated, Central Valleyno Central Valley ratingToogBischofia javanicanot rated, Central Valleyno Central Valley ratingClustered Fishtail PalmCaryota mitisnot rated, Central Valleyno Central Valley ratingWhite SapoteCasimiroa edulisnot rated, Central Valleyno Central Valley ratingFilbertCorylus maximanot rated, Central Valleyno Central Valley ratingSpotted GumCorymbia maculata (Eucalyptus maculata)not rated, Central Valleyno Central Valley ratingDove TreeDavidia involucratanot rated, Central Valleyno Central Valley ratingRoyal PoincianaDelonix regianot rated, Central Valleyno Central Valley ratingMountain White GumEucalyptus dalrympleananot rated, Central Valleyno Central Valley ratingRainbow EucalyptusEucalyptus degluptanot rated, Central Valleyno Central Valley ratingRoxburgh FigFicus auriculatanot rated, Central Valleyno Central Valley ratingIndian BanyanFicus benghalensisnot rated, Central Valleyno Central Valley ratingWeeping Chinese BanyanFicus benjaminanot 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 triangle palm, 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 triangle palm in summer?

In July, established triangle palm in loam needs a deep watering 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 triangle palm need per day?

In July on the south coast, established triangle palm needs about 5.0 gallons a day under a 10 foot canopy and about 20 gallons a day under a 20 foot canopy. Give it in deep waterings spread days apart rather than a little every day, so the whole root zone gets wet.

Does watering for triangle palm change across California?

Yes. WUCOLS rates triangle palm 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, moderate 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, 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 triangle palm prone to disease?

It is rated mostly disease resistant among palms common in California. Good drainage still matters. Overwatering invites root problems in any palm.

What is the South American palm weevil?

It is an invasive pest of palms that has reached California. Triangle palm is one of its confirmed hosts there. Watch the crown for decline.

Can triangle palm grow on the coast north of Santa Barbara?

WUCOLS marks it as not suited to the north-central coast. Its two rated zones are both in the warm south. Choose another palm farther north.

Can triangle palm grow in a pot?

Yes, it can grow in a large, heavy container. Use a fast-draining mix. Water once the upper mix has dried.

Should I cut triangle palm fronds?

Remove only dead fronds. Green fronds feed the palm. Clean tools between palms.

More plant watering guides

CopperleafSugar MapleDesert RoseQueensland KauriGolden Trumpet VineCherimoyaJapanese ArdisiaPelican Flower

Sources