WateringTimesWatering plan, $19
Juniperus spp. & cvs., WUCOLS IV

How often to water junipers in California

In July in the Central Valley, established junipers in loam need a deep watering about every 20 days: about 55 gallons each time under a 10 foot canopy, about 19 gallons a week. Junipers range from spreading mats to upright conifers, keeping needle or scale foliage through the year. Their branches give fewer visible wilt cues than a soft-leaved shrub. Check moisture below the surface and allow drainage between soakings, especially where heavy ground stays wet.

Ground coverShrubTreeRated for 6 of 6 zones

How often to water junipers, 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 junipers 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

  • Dry surface soil beneath a juniper calls for a deeper root-zone check before another soaking
  • Foliage fading to a dull cast can accompany thirst, so compare its color with soil moisture
  • Browning outer tips after a long dry spell can indicate water shortage or reflected heat
  • Yellowing branches over persistently damp ground can indicate poor drainage or root trouble
  • Old needles browning and shedding inside the plant in fall can be normal aging rather than thirst

How to water it

  • Water beneath the spread of the juniper branches instead of keeping one wet spot against the trunk
  • Moisten soil about 12 to 18 inches deep beneath established junipers, checking penetration across the spreading mat or upright canopy
  • Use drip or a soaker line beneath the dense foliage
  • Plant slightly high in heavy clay and keep gravel or coarse bark mulch clear of the trunk
  • Move emitters outward as a spreading juniper widens to cover roots near the mat edge

Through the seasons

Keep a new juniper root ball moist through its first summer, expanding the watered circle as roots enter the surrounding soil. Established plants can take deeper, more widely spaced soakings. Junipers keep their foliage through winter, while growth and water use slow in cool weather. Coastal and Central Valley rain can supply winter moisture; check desert plantings through dry gaps as well as the longer warm season. WUCOLS rates junipers low water on the north-central coast, in the Central Valley, on the south coast and in South Inland. They rate moderate water in the high desert and the low desert.

In pots

Juniper roots in a container depend on a limited volume of mix, especially in California summer heat. Check the top inch or two often and water when it dries, soaking until excess leaves the drainage holes. Empty the saucer so roots do not remain submerged. A shallow bonsai pot needs closer checks than a larger container. Keep junipers outdoors, and continue moisture checks during winter wind or dry spells, particularly beneath eaves.

1 Your climate zone six WUCOLS zones, each from its own reference city
1.07gal per sq ft in JulyLow water use in the Central Valley zone
A year
6.84 gal per sq ft
Reference
Sacramento climate table
Counts
Plant need, before sprinkler losses
0.761.52.33.00.16JAN0.26FEB0.43MAR0.61APR0.83MAY0.99JUN1.07JUL0.95AUG0.72SEP0.47OCT0.22NOV0.14DEC0.761.52.33.00.16JFM0.61AMJ1.07JAS0.47OND
Gallons per square foot per month, Central Valley. Peak 1.07 in Jul, 6.84 a year.

Monthly water need by climate zone

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

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.150.160.310.310.740.78
Feb0.210.260.320.350.930.93
Mar0.350.430.460.521.461.52
Apr0.470.610.560.641.891.95
May0.580.830.640.782.392.45
Jun0.640.990.690.922.852.79
Jul0.641.070.7913.042.85
Aug0.60.950.740.932.792.6
Sep0.50.720.60.742.142.08
Oct0.350.470.460.531.461.49
Nov0.190.220.330.360.930.96
Dec0.120.140.260.270.650.68
Year4.86.846.27.3721.2721.08

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 low water in the Central Valley, like junipers. Plants that drink alike can share one valve and one schedule.

LavenderLavandula spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyRosemaryRosmarinus officinalislow water, Central Valley1.07 gal/sq ft in JulyBougainvilleaBougainvillea & spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyOlive TreesOlea europaea ssp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyFig TreesFicus carica ssp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyCrape MyrtleLagerstroemia spp., hybrids & cvs.low water, Central Valley1.07 gal/sq ft in JulyLantanaLantana camara ssp. & cvs.low water, Central Valley1.07 gal/sq ft in JulySalviaSalvia greggii ssp., cvs. & hybridslow water, Central Valley1.07 gal/sq ft in JulyAloeAloe spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulySucculentsEcheveria spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyPomegranate TreesPunica granatumlow water, Central Valley1.07 gal/sq ft in JulyEucalyptusEucalyptus polyanthemoslow water, Central Valley1.07 gal/sq ft in JulyPine TreesPinus canariensislow water, Central Valley1.07 gal/sq ft in JulyRussian SagePerovskia spp. & cvs.low water, Central Valley1.07 gal/sq ft in JulyYarrowAchillea millefolium (non-native hybrids)low water, Central Valley1.07 gal/sq ft in JulySagebrushArtemisia spp. (shrubby)low water, Central Valley1.07 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 junipers, 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 junipers in summer?

In July, established junipers in loam need a deep watering about every 20 days in the Central Valley, about every 27 days on the south coast and about every 22 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 do junipers need per day?

In July in the Central Valley, established junipers need about 2.7 gallons a day under a 10 foot canopy and about 11 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 junipers change across California?

Yes. WUCOLS rates junipers separately for each of the six California climate zones: low water in the North-Central Coastal zone, low water in the Central Valley zone, low water in the South Coastal zone, low water in the South Inland zone, moderate water 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.

How do I water a juniper after planting?

Feel the nursery root ball separately from the surrounding ground. Water it before it dries hard, without leaving it soggy. Widen the soaked area during establishment as roots spread beyond the planting hole.

Can you overwater junipers?

Yes. Lawn irrigation can keep the root zone wetter than a juniper needs. Check below the surface before repeating a soak and separate its watering from turf if the soil stays saturated.

Why is one side of my juniper turning brown?

Compare moisture on that side with the rest of the root area. Wet ground can indicate a drainage problem, while dry roots or heat reflected from paving can damage exposed tips. Browning alone does not identify the cause.

How do I check a juniper bonsai for water?

Use a finger or wooden skewer to test below the surface. A shallow pot can need checks more than once during a hot day. Do not wait for the needles to wilt before checking the mix.

Can I keep a juniper bonsai indoors?

Junipers are outdoor conifers and generally do poorly as houseplants. They need direct light, moving air and seasonal cool weather. Keep an indoor display brief and return the plant outside.

More plant watering guides

Winter-Blooming BergeniaBottle TreeBlue Hesper PalmQuaking GrassShrubby Hare's EarDwarf PoincianaBottle BrushEuropean Gray Sedge

Sources