WateringTimesWatering plan, $19
Agave tequilana & ssp. & cvs., WUCOLS IV

How often to water blue agave in California

In July in the Central Valley, established blue agave needs about 0.2 gallons a week for a plant 2 feet across. Blue agave, the tequila agave, is a fast-growing succulent with a rosette about 5 feet across. Its narrow, blue-gray leaves end in sharp brown spines. It sends up pups at its base and on rhizomes several feet away. It needs full sun, fast drainage and very little water, and frost limits where it can grow.

SucculentRated for 6 of 6 zones

How often to water blue agave, 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 blue agave and the rest of your yard, on the days your water supplier allows.Get the plan for $19

How this is worked out: the plant’s WUCOLS rating times your city’s climate for the month, over the area the plant covers. 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

  • Leaves thinning, wrinkling or curling inward in a long summer drought can show the rosette is drawing on stored water
  • Leaves yellowing and softening near the base, or a mushy center, point to rot from too much water or slow drainage
  • Brown, collapsed leaf tissue after a cold night is frost damage, not a sign of thirst
  • Pups popping up several feet from the parent are normal spread from underground rhizomes
  • A tall flower stalk means the rosette is nearing the end of its life, since most agaves bloom once

How to water it

  • Plant in full sun in sandy or gravelly soil that drains fast, or on a raised mound
  • Water a new planting deeply only when the soil is dry several inches down, then taper off as it roots in
  • Once it is established, give an occasional deep soak only during long, hot dry spells
  • Apply water to the soil around the rosette, never into the center of the leaves
  • Leave open ground around it, since pups appear several feet out, and keep the watered area small

Through the seasons

A newly planted blue agave needs an occasional deep soak in its first summer while its roots spread. After that it needs very little water. It stays evergreen and grows fastest in warm weather. Rain usually covers the cool months on the coast and in the Central Valley, and wet winter soil is a rot risk. Frost below about 25 degrees can damage it, which limits it in colder inland gardens. WUCOLS rates blue agave very low water on the north-central coast, in the Central Valley and in South Inland. The high desert and the low desert share that very low water rating, while the south coast rates low water.

In pots

Blue agave grows quickly for a succulent, so give it a wide pot and a gritty cactus mix. Water deeply only when the mix is dry most of the way down, then let it drain completely and leave the saucer empty. In cool weather it needs very little water at all. A pot is easy to move under cover when frost threatens, which matters wherever winters drop below the mid 20s. Wear gloves when handling it, since the leaf tips are sharp.

1 Your climate zone six WUCOLS zones, each from its own reference city
0.27gal per sq ft in JulyVery low water use in the Central Valley zone
A year
1.71 gal per sq ft
Reference
Sacramento climate table
Counts
Plant need, before sprinkler losses
0.200.400.590.790.04JAN0.07FEB0.11MAR0.15APR0.21MAY0.25JUN0.27JUL0.24AUG0.18SEP0.12OCT0.06NOV0.03DEC0.200.400.590.790.04JFM0.15AMJ0.27JAS0.12OND
Gallons per square foot per month, Central Valley. Peak 0.27 in Jul, 1.71 a year.

Monthly water need by climate zone

Blue Agave: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.040.040.310.080.070.08
Feb0.050.070.320.090.090.09
Mar0.090.110.460.130.150.15
Apr0.120.150.560.160.190.2
May0.150.210.640.20.240.24
Jun0.160.250.690.230.290.28
Jul0.160.270.790.250.30.29
Aug0.150.240.740.230.280.26
Sep0.120.180.60.190.210.21
Oct0.090.120.460.130.150.15
Nov0.050.060.330.090.090.1
Dec0.030.030.260.070.070.07
Year1.21.716.21.842.132.11

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 13

Rated very low water in the Central Valley, like blue agave. Plants that drink alike can share one valve and one schedule.

CactusOpuntia spp. & cvs. (CA natives and non-natives)very low water, Central Valley0.27 gal/sq ft in JulyCypress SpurgeEuphorbia cyparissiasvery low water, Central Valley0.27 gal/sq ft in JulyVariegated Century PlantAgave americana var. marginatavery low water, Central Valley0.27 gal/sq ft in JulyDesert AgaveAgave desertivery low water, Central Valley0.27 gal/sq ft in JulyThread Leaf AgaveAgave filiferavery low water, Central Valley0.27 gal/sq ft in JulyPalmer AgaveAgave palmerivery low water, Central Valley0.27 gal/sq ft in JulyButterfly AgaveAgave potatorumvery low water, Central Valley0.27 gal/sq ft in JulySisalAgave sisalanavery low water, Central Valley0.27 gal/sq ft in JulyCentury PlantAgave spp. & cvs.very low water, Central Valley0.27 gal/sq ft in JulyUtah AgaveAgave utahensisvery low water, Central Valley0.27 gal/sq ft in JulyQueen Victoria AgaveAgave victoriae-reginaevery low water, Central Valley0.27 gal/sq ft in JulyBeaked YuccaYucca rostrata ssp. & cvs.very low water, Central Valley0.27 gal/sq ft in JulyParry's AgaveAgave parryivery low water, Central Valley0.27 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 blue agave, 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 should I water blue agave in summer?

In July, established blue agave needs about 0.2 gallons in the Central Valley, 0.6 gallons on the south coast and 0.2 gallons in the South Inland zone each week, for a plant 2 feet across. Water deeply and let the top of the soil dry before the next watering. Skip a watering after a soaking rain.

How much water does blue agave need per day?

In July in the Central Valley, established blue agave needs about 0.0 gallons a day for a plant 2 feet across and about 0.1 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 blue agave change across California?

Yes. WUCOLS rates blue agave separately for each of the six California climate zones: very low water in the North-Central Coastal zone, very low water in the Central Valley zone, low water in the South Coastal zone, very low water in the South Inland zone, very low water in the High and Intermediate Desert zone, very 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.

Does blue agave die after flowering?

Like most agaves, it blooms once at the end of its life, and the rosette dies after the flower stalk. Pups around the base carry on. Leave them in place or replant them.

How cold can blue agave handle?

It needs winters that stay above about 25 degrees F, and long spells near 27 degrees can also hurt it. That limits it mostly to Southern California coastal areas and the low desert. Elsewhere, grow it in a pot and shelter it in cold snaps.

How do I control blue agave pups?

It sends pups from the base and on rhizomes several feet away. Dig unwanted pups while they are small, wearing gloves and eye protection against the spines. Pups make easy new plants.

Is this the agave used for tequila?

Yes. Its blue form is the preferred crop for tequila in Mexico, where it has been grown since before the Spanish arrived. Garden plants need the same sun and sharp drainage as the farm crop.

Why is my blue agave rotting?

Rot usually follows too much water, poor drainage or water sitting in the rosette. Stop irrigating and let the soil dry. If the center has collapsed, replant healthy pups in gritty soil.

More plant watering guides

Century PlantUtah AgaveQueen Victoria AgaveCreosote BushPurple SageBlack SageBeaked YuccaCalifornia Buckeye

Sources