How often to water tufted hairgrass in California
In July in the Central Valley, established tufted hairgrass needs about 0.8 gallons a week for a plant 2 feet across. Tufted hairgrass is a cool-season bunchgrass of mountain meadows and seasonally wet places, with fine, dark green leaves in a dense tuft. In summer it sends up airy clouds of tiny flowers that fade to golden straw and last into winter. It tolerates wet and even seasonally flooded soil, likes light shade, and struggles in hot interior summers.
How often to water tufted hairgrass, month by month
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.
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.
How to tell it needs water
- Soil dry 3 inches down around a young clump in its first summer signals that it needs a soak
- Leaves browning and the tuft looking ragged in summer heat point to too much sun and heat as well as dry soil
- Flower heads turning straw-colored in late summer are normal ripening, not thirst
- Soggy soil seldom harms this meadow grass, so look at heat and sun first when a wet clump declines
- Seedlings appearing around the clump are normal, since it self-seeds
How to water it
- During dry spells, run drip or a soaker line around the tuft rather than spraying it
- Moisten the root zone to about a foot down, waiting for the top 2 or 3 inches to dry before the next soak
- Plant in light to moderate shade in humus-rich soil, or in more sun on a cool coastal site
- Cut old foliage to the ground in late winter before new growth starts
- Use it in a rain garden or a low spot that collects winter water, where it thrives
Through the seasons
A new tufted hairgrass needs steady moisture through its first summer while its roots settle. Established clumps get by on less where they rate low water, though inland heat calls for shade and closer soil checks. As a cool-season grass it grows mostly in spring and fall, flowers in summer and stays semi-evergreen. Rain usually carries it through winter on the coast and in the Central Valley. WUCOLS rates tufted hairgrass low water on the north-central coast and in the Central Valley. It rates moderate water on the south coast. WUCOLS marks it as not suited to South Inland and has not evaluated it for the high desert or the low desert.
In pots
Tufted hairgrass grows well in a pot in light shade, where its airy flower clouds sit at eye level. Check the mix 2 inches down every few days in summer and water when it dries. Let the excess drain out, then empty the saucer, though a little lingering dampness does it no harm. Keep the pot out of hot afternoon sun inland. Cut the old leaves to the base in late winter and water as fresh growth starts.
- A year
- 6.84 gal per sq ft
- Reference
- Sacramento climate table
- Counts
- Plant need, before sprinkler losses
Monthly water need by climate zone
Tufted Hairgrass: gallons per square foot per month, by WUCOLS climate zone
| Month | N. Coast | C. Valley | S. Coast | S. Inland | Hi Desert | Lo Desert |
|---|---|---|---|---|---|---|
| Jan | 0.15 | 0.16 | 0.78 | – | – | – |
| Feb | 0.21 | 0.26 | 0.81 | – | – | – |
| Mar | 0.35 | 0.43 | 1.15 | – | – | – |
| Apr | 0.47 | 0.61 | 1.4 | – | – | – |
| May | 0.58 | 0.83 | 1.61 | – | – | – |
| Jun | 0.64 | 0.99 | 1.74 | – | – | – |
| Jul | 0.64 | 1.07 | 1.98 | – | – | – |
| Aug | 0.6 | 0.95 | 1.86 | – | – | – |
| Sep | 0.5 | 0.72 | 1.49 | – | – | – |
| Oct | 0.35 | 0.47 | 1.15 | – | – | – |
| Nov | 0.19 | 0.22 | 0.84 | – | – | – |
| Dec | 0.12 | 0.14 | 0.65 | – | – | – |
| Year | 4.8 | 6.84 | 15.5 | – | – | – |
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 tufted hairgrass. Plants that drink alike can share one valve and one schedule.
Quaking GrassBriza medialow water, Central Valley1.07 gal/sq ft in July
June GrassKoeleria macrantha (cristata)low water, Central Valley1.07 gal/sq ft in July
False Esparto GrassLygeum spartumlow water, Central Valley1.07 gal/sq ft in July
Blue FescueFestuca glauca ssp. & cvs.low water, Central Valley1.07 gal/sq ft in July
Baltic RushJuncus balticuslow water, Central Valley1.07 gal/sq ft in July
Giant Needle GrassStipa gigantealow water, Central Valley1.07 gal/sq ft in July
California Native YarrowAchillea millefolium (CA native cultivars)low water, Central Valley1.07 gal/sq ft in July
Perennial HollyhockAlcea rosea cvs.low water, Central Valley1.07 gal/sq ft in July
MadroneArbutus menziesiilow water, Central Valley1.07 gal/sq ft in July
MacNab CypressHesperocyparis macnabiana (Cupressus macnabiana)low water, Central Valley1.07 gal/sq ft in July
California JuniperJuniperus californicalow water, Central Valley1.07 gal/sq ft in July
Lippia GroundcoverPhyla nodiflora (Lippia nodiflora) cvs.low water, Central Valley1.07 gal/sq ft in July
Knobcone PinePinus attenuatalow water, Central Valley1.07 gal/sq ft in July
Coulter PinePinus coulterilow water, Central Valley1.07 gal/sq ft in July
Pinyon PinePinus edulislow water, Central Valley1.07 gal/sq ft in July
Jeffrey PinePinus jeffreyilow water, Central Valley1.07 gal/sq ft in JulyTurn this into minutes on your water days
Every city page has a calculator that takes tufted hairgrass, 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 tufted hairgrass in summer?
In July, established tufted hairgrass needs about 0.8 gallons in the Central Valley and 1.4 gallons on the south coast 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 tufted hairgrass need per day?
In July in the Central Valley, established tufted hairgrass needs about 0.1 gallons a day for a plant 2 feet across and about 0.4 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 tufted hairgrass change across California?
Yes. WUCOLS rates tufted hairgrass separately for each of the six California climate zones: low water in the North-Central Coastal zone, low water in the Central Valley zone, moderate water 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.
Can tufted hairgrass grow in full sun?
It grows in full sun, but its foliage and flowers look better in light to moderate shade. In hot interior gardens it struggles in sun, while cool coastal gardens suit it better.
When should I cut back tufted hairgrass?
Cut the old foliage to the ground in late winter, before new growth starts. The clump then fills out fresh in spring. Water if the soil is dry when growth resumes.
Is tufted hairgrass native to California?
Yes. It grows wild in mountain meadows, along streambanks and in seasonally damp spots across much of western North America, including California.
Can tufted hairgrass take wet soil?
Yes. It tolerates moist to soggy soil and even seasonal flooding, which makes it useful in rain gardens and low spots. It also tolerates salt.
Are tufted hairgrass flowers good for cutting?
Yes, the airy flower heads work well as cut flowers. They open green to gold in summer and dry to straw, lasting into winter on the plant.
More plant watering guides
Sources
- WUCOLS IV plant water use classification for Deschampsia cespitosa and cvs., the University of California survey California agencies use for landscape plan reviewRead August 23, 2026 on wucols.ucdavis.edu
- Model Water Efficient Landscape Ordinance, adopted text and appendices, effective 2025-01-02 · monthly reference evapotranspiration per city, Appendix CRead August 23, 2026 on water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/Water-Use-And-Efficiency/MWELO-Rulemaking/Final-MWELO-Text-and-Appendices_20250103.pdf
- UC Statewide IPM Program, irrigation scheduling using evapotranspirationRead September 30, 2026 on ipm.ucanr.edu/PMG/GARDEN/ENVIRON/evap.html
- Shaw and Pittenger, Landscape Irrigation System Evaluation and Management, UC Cooperative Extension, 2009Read September 30, 2026 on ucanr.edu/sites/default/files/2013-02/160836.pdf
- Pittenger, Water Management in Gardens and Landscapes, UC Riverside, 2017Read September 30, 2026 on ucanr.edu/sites/default/files/2017-03/258022.pdf