WateringTimesWatering plan, $19
Zamia furfuracea, WUCOLS IV

How often to water cardboard palm in California

In July on the south coast, established cardboard palm in loam needs a deep watering about every 11 days: about 8.8 gallons each time under a 4 foot canopy, about 5.6 gallons a week. Cardboard palm is not a palm but a slow-growing cycad from the coastal mountains and limestone sea cliffs of Veracruz, Mexico. Stiff, fuzzy leaflets with a cardboard feel sit on leaves that radiate from a short, often buried trunk. It grows only 3 to 4 feet tall and wants well-drained soil with regular water through the warm months.

ShrubPalm or cycadRated for 3 of 6 zones

How often to water cardboard palm, month by month

Your city
Canopy 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 cardboard 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

  • Leaflets on cardboard palm curling or dulling while the soil is dry several inches down mean it needs water
  • Lower leaves yellowing on soil that stays wet point to overwatering and poor drainage
  • Leaflets browning after a hard frost point to cold damage, not thirst
  • Soil that stays damp for many days after a soak points to drainage too slow for this cycad

How to water it

  • Water deeply around the trunk when the top couple of inches of soil dry
  • Plant in full sun or light shade in well-drained, sandy soil
  • Water regularly from spring through fall and much less in winter
  • Keep mulch a few inches back from the trunk
  • Remove cones from female plants where pets play, since the seeds are poisonous

Through the seasons

Water a new plant regularly while it roots in, and expect slow growth. Established plants want regular water from spring through fall, when new leaves flush. It is evergreen, and on the south coast winter rain usually covers the cool months. Protect it when frost threatens, since it is hardy only to about 25 degrees F. WUCOLS rates cardboard palm moderate water on the south coast, in South Inland and in the low desert. WUCOLS marks it as not suited to the north-central coast, the Central Valley or the high desert.

In pots

Cardboard palm makes a tidy container plant and can live indoors in bright light. Use a pot with several drainage holes and a sandy, well-drained mix. Let the top inch or two dry between waterings, then water until it drains out. On hot patios in summer, check every few days. Do not leave water in the saucer. In winter, water sparingly and bring it in before frost.

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

WUCOLS lists Cardboard 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

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

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan––0.780.78–0.78
Feb––0.810.87–0.93
Mar––1.151.3–1.52
Apr––1.41.61–1.95
May––1.611.95–2.45
Jun––1.742.29–2.79
Jul––1.982.51–2.85
Aug––1.862.33–2.6
Sep––1.491.86–2.08
Oct––1.151.33–1.49
Nov––0.840.9–0.96
Dec––0.650.68–0.68
Year––15.518.41–21.08

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 cardboard palm. 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 ratingTriangle PalmDypsis decaryinot rated, Central Valleyno Central Valley ratingPoinsettiaEuphorbia pulcherrimanot 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 ratingKentia PalmHowea forsteriananot rated, Central Valleyno Central Valley ratingJungle GeraniumIxora coccineanot rated, Central Valleyno Central Valley ratingAustralian Fountain PalmLivistona australisnot rated, Central Valleyno Central Valley ratingOrange JessamineMurraya paniculatanot 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 cardboard 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 cardboard palm in summer?

In July, established cardboard 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 cardboard palm need per day?

In July on the south coast, established cardboard palm needs about 0.8 gallons a day under a 4 foot canopy and about 3.2 gallons a day under a 8 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 cardboard palm change across California?

Yes. WUCOLS rates cardboard 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, moderate water in the Low Desert zone. The monthly table above shows how the same rating translates into different gallon amounts as reference evapotranspiration changes.

Is cardboard palm a real palm?

No, it is a cycad, which forms cones instead of flowers. Its leaves only look like palm fronds. Females carry egg-shaped cones and males smaller cone clusters.

Is cardboard palm poisonous?

Yes, the seeds are poisonous to people, cats, dogs and horses. Remove cones from female plants if pets or children play nearby. Wash your hands after handling seeds.

How cold can cardboard palm take?

It handles brief dips to about 25 degrees F. Longer or harder freezes damage the leaves. Cover it or bring pots inside on frosty nights.

Can cardboard palm grow indoors?

Yes, it does well as a house plant in bright light. Its slow growth keeps it in scale for years. Let the mix dry between waterings.

Is cardboard palm drought tolerant?

It handles short dry spells once established, but it is not a dry garden plant here. Regular water from spring through fall keeps the leaves full. Good drainage matters as much as the water itself.

More plant watering guides

Purple Orchid TreeToogMagic FlowerClustered Fishtail PalmWhite SapoteHawaiian TiFilbertSpotted Gum

Sources