WateringTimesWatering plan, $19
Phlox subulata, WUCOLS IV

How often to water moss pink in California

In July in the Central Valley, established moss pink in loam needs a deep watering about every 8 days: about 2.2 gallons each time for a plant 2 feet across, about 1.9 gallons a week. Moss pink, also called creeping phlox, is a mat-forming perennial native to central and eastern North America. It grows up to 6 inches tall and 2 to 3 feet wide, with needle-like leaves, and in spring it is covered in pink, lavender, purple or white flowers. It handles hot, dry conditions better than most phlox but still likes humus-rich soil.

Ground coverRated for 2 of 6 zones

How often to water moss pink, 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 moss pink 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 the plant covers, 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 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

  • Soil dry 2 inches down under the mat in summer means moss pink is ready for water
  • Needle-like leaves turning dull and tan in patches during a dry spell suggest thirst
  • The center of an old mat thinning out is normal aging, not a water problem
  • Stems rotting in wet, heavy soil point to poor drainage

How to water it

  • Water at the edge of the mat with a gentle hose or drip
  • Moisten the soil about 4 to 6 inches deep, then let the top inch dry
  • Plant in full sun in humus-rich, sandy or gravelly, well-drained soil
  • Give it dappled light in the hottest inland gardens
  • Cut stems back by half after flowering

Through the seasons

Water new plants regularly until they knit together. Established mats want moderate water through summer, though they tolerate dry spells better than other phlox. Bloom comes in spring, and a trim afterward keeps the mat dense. Older plantings thin in the middle as growth spreads outward. WUCOLS rates moss pink moderate water on the north-central coast and in the Central Valley. WUCOLS marks it as not suited to the south coast or South Inland, and has not evaluated it for the high desert or the low desert.

In pots

Moss pink can spill over the edge of a pot, wall planter or trough. Use a gritty, well-drained mix with some compost. Water once the top inch feels dry, then let excess drain. In summer, small pots can need water every day or two. Empty the saucer so stems stay dry. Shear it by half after bloom to keep it dense. In winter, water only when the mix dries.

1 Your climate zone six WUCOLS zones, each from its own reference city
2.67gal per sq ft in JulyModerate water use in the Central Valley zone
A year
17.11 gal per sq ft
Reference
Sacramento climate table
Counts
Plant need, before sprinkler losses
0.671.32.02.70.4JAN0.65FEB1.09MAR1.52APR2.08MAY2.48JUN2.67JUL2.39AUG1.8SEP1.18OCT0.56NOV0.34DEC0.671.32.02.70.4JFM1.52AMJ2.67JAS1.18OND
Gallons per square foot per month, Central Valley. Peak 2.67 in Jul, 17.11 a year.

Monthly water need by climate zone

Moss Pink: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.370.4––––
Feb0.530.65––––
Mar0.871.09––––
Apr1.181.52––––
May1.462.08––––
Jun1.612.48––––
Jul1.612.67––––
Aug1.492.39––––
Sep1.241.8––––
Oct0.871.18––––
Nov0.470.56––––
Dec0.310.34––––
Year1217.11––––

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 16

Rated moderate water in the Central Valley, like moss pink. Plants that drink alike can share one valve and one schedule.

Similar plants that need less water 16

Rated lower than moss pink in the Central Valley. Worth a look for a new bed or a lawn replacement.

Minutes for your sprinklers

Turn this into minutes on your water days

Every city page has a calculator that takes moss pink, 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 water does moss pink need per day?

In July in the Central Valley, established moss pink needs about 0.3 gallons a day for a plant 2 feet across and about 1.1 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 moss pink change across California?

Yes. WUCOLS rates moss pink separately for each of the six California climate zones: moderate water in the North-Central Coastal zone, moderate water in the Central Valley zone, not suited to this region in the South Coastal zone, not suited to this region in the South Inland zone, not evaluated in the High and Intermediate Desert zone, not evaluated in the Low Desert zone. The monthly table above shows how the same rating translates into different gallon amounts as reference evapotranspiration changes.

Should I cut back moss pink after it blooms?

Yes, cut stems back by half after flowering. That keeps the shape and encourages dense growth. Water afterward to push new growth.

Why is my moss pink bare in the middle?

Older plantings thin out as new growth spreads away from the center. Trimming after bloom helps. Replant pieces into bare spots.

Does moss pink need full sun?

It flowers best in full sun. In hot summers it appreciates dappled light. Shade cuts bloom.

Is moss pink deer resistant?

It tolerates deer, erosion, drought and air pollution. It works on slopes and in rock gardens. It drapes nicely over low walls.

What soil does moss pink like?

It likes sandy or gravelly soil that is humus rich and well drained. Heavy, wet soil invites rot. Add grit to clay.

More plant watering guides

Sources