WateringTimesWatering plan, $19
Pinus monophylla, WUCOLS IV

How often to water single-leaf pinyon pine in California

In July on the north-central coast, established single-leaf pinyon pine in loam needs a deep soak only about once a month or less: about 55 gallons each time under a 10 foot canopy. Single-leaf pinyon pine is a small, slow, broad-crowned native of California's dry mountain slopes, with a dark trunk. Its frosty gray needles grow singly, unlike any other pine, and its small cones hold a few large, edible pine nuts. It is a tree for semi-arid conditions and needs little or no summer water once established.

TreeCalifornia nativeRated for 4 of 6 zones

How often to water single-leaf pinyon pine, 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 single-leaf pinyon pine 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

  • In its first summers, a new pinyon can use a deep soak once soil at the root ball edge dries a few inches down
  • Needles yellowing and a thinning crown over soil kept moist in summer point to root rot, a real risk for this dry-country pine
  • Very slow growth is normal for this pine, not a sign that it needs more water
  • Sticky needles with clusters of tiny insects point to aphids rather than water stress
  • Pitch tubes or boring dust on the trunk during a long drought point to bark beetles attacking a stressed tree

How to water it

  • Water a new planting deeply, but only after the soil has dried, for its first two summers
  • After the second summer, stop regular irrigation and give only a rare deep soak in a severe drought
  • Plant in full sun or light shade in fast-draining sandy or rocky soil, which may be alkaline
  • Keep it apart from lawns and garden beds that get summer water
  • Use gravel or bare soil around the trunk rather than organic mulch that stays damp

Through the seasons

A newly planted single-leaf pinyon pine needs occasional deep soakings through its first two summers while its roots reach down. After that it can go without regular summer water, and wet summer soil invites root rot. It stays evergreen and grows very slowly, only a few feet in its first several years, and nuts take many years to appear. WUCOLS rates single-leaf pinyon pine low water on the north-central coast, in South Inland and in the high desert. It rates very low water on the south coast. WUCOLS marks it as not suited to the Central Valley or the low desert.

In pots

Single-leaf pinyon pine grows slowly enough to live for years in a container, and it makes a good bonsai. Use a gritty, fast-draining mix and water only when it is dry most of the way down. Let water drain through completely, and never leave the pot standing in a saucer. Give it full sun and good air. In winter, water rarely and let rain do much of the work, since this dry-country pine is prone to root rot.

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

WUCOLS lists Single-Leaf Pinyon Pine as not suited to this region for the Central Valley zone, so no monthly figure is computed here.

Monthly water need by climate zone

Single-Leaf Pinyon Pine: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.15–0.080.310.3–
Feb0.21–0.080.350.37–
Mar0.35–0.110.520.58–
Apr0.47–0.140.640.76–
May0.58–0.160.780.95–
Jun0.64–0.170.921.14–
Jul0.64–0.211.22–
Aug0.6–0.190.931.12–
Sep0.5–0.150.740.86–
Oct0.35–0.110.530.58–
Nov0.19–0.080.360.37–
Dec0.12–0.070.270.26–
Year4.8–1.557.378.51–

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 suited to this region in the Central Valley, like single-leaf pinyon pine. 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 ratingTriangle PalmDypsis decaryinot 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 rating
Minutes for your sprinklers

Turn this into minutes on your water days

Every city page has a calculator that takes single-leaf pinyon pine, 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 single-leaf pinyon pine in summer?

In July, established single-leaf pinyon pine in loam needs a deep watering about once a month or less 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 does single-leaf pinyon pine need per day?

In July on the north-central coast, established single-leaf pinyon pine needs about 1.6 gallons a day under a 10 foot canopy and about 6.5 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 single-leaf pinyon pine change across California?

Yes. WUCOLS rates single-leaf pinyon pine separately for each of the six California climate zones: low water in the North-Central Coastal zone, not suited to this region in the Central Valley zone, very low water in the South Coastal zone, low water in the South Inland zone, low water 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.

Why does single-leaf pinyon have single needles?

It is the only pine whose needles grow one at a time instead of in bundles of two to five. That trait gives the tree its name and its frosty gray look. It is natural, not a sign of stress.

When will my pinyon pine produce nuts?

Be patient, since a tree can take around 20 years to bear. Each cone then holds a few large, edible nuts. Keep the tree healthy on little water in the meantime.

How big does single-leaf pinyon pine get?

It grows very slowly to about 15 to 30 feet tall, low-branched and broad. Expect only a few feet of growth in its first several years.

Can single-leaf pinyon grow in a lawn?

No. It is a dry-country pine, and regular lawn watering invites root rot. Plant it with other drought-adapted plants that need little summer water.

Is single-leaf pinyon native to California?

Yes. It grows in the Peninsular and Transverse ranges and along the eastern flanks of the Sierra Nevada. It also climbs the upper slopes of desert mountains, often near junipers and sagebrush.

More plant watering guides

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Sources