How often to water summer snowflake in California
In July in the Central Valley, established summer snowflake needs about 0.8 gallons a week for a plant 2 feet across. Summer snowflake is a spring bulb with strap-shaped leaves and nodding white bells tipped in green, two to five to a stem. Despite its name, it blooms in mid-spring, then goes dormant through summer. It comes from seasonally damp places, so it needs steady moisture while growing and tolerates drought once the leaves are gone.
How often to water summer snowflake, 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 2 inches down while the leaves are up signals that summer snowflake needs water
- Short stems and few flowers can follow a dry spring, since the bulbs need moisture to bloom well
- Leaves yellowing and dying back after bloom mark summer dormancy, not drought
- Soggy spring soil seldom harms this damp-ground bulb, so a weak clump more likely needs more light or less acidic soil
- Holes in the leaves and flowers point to slugs and snails, not a watering problem
How to water it
- Plant bulbs 2 to 4 inches deep and about 6 inches apart in fall, then leave them undisturbed
- Keep the soil consistently moist from fall growth through spring bloom, watering when rain falls short
- Let the bed dry once the leaves yellow, since dormant bulbs tolerate summer drought
- Give it organic, well-drained but damp soil in sun or part shade, avoiding acidic ground
- Plant it under deciduous trees or in a low spot where spring moisture lingers
Through the seasons
Summer snowflake grows on the cool-season calendar. Leaves come up during the cool months, flowers open in mid-spring, and the foliage dies back as summer arrives. Steady moisture during growth is what makes it bloom well. Winter rain usually provides much of it on the coast and in the Central Valley. Dormant bulbs tolerate summer drought. WUCOLS rates summer snowflake moderate water on the north-central coast and in South Inland. It rates low water in the Central Valley and on the south coast. WUCOLS has not evaluated it for the high desert or the low desert.
In pots
Summer snowflake can bloom in a deep pot for a few seasons, though it prefers to settle undisturbed in the ground. Plant bulbs in fall and keep the mix evenly moist through winter and spring growth. Check it an inch down every few days in dry weather. Let water drain through, then empty the saucer. After the leaves die back, let the pot dry out and keep it in shade through summer.
- A year
- 6.84 gal per sq ft
- Reference
- Sacramento climate table
- Counts
- Plant need, before sprinkler losses
Monthly water need by climate zone
Summer Snowflake: gallons per square foot per month, by WUCOLS climate zone
| Month | N. Coast | C. Valley | S. Coast | S. Inland | Hi Desert | Lo Desert |
|---|---|---|---|---|---|---|
| Jan | 0.37 | 0.16 | 0.31 | 0.78 | – | – |
| Feb | 0.53 | 0.26 | 0.32 | 0.87 | – | – |
| Mar | 0.87 | 0.43 | 0.46 | 1.3 | – | – |
| Apr | 1.18 | 0.61 | 0.56 | 1.61 | – | – |
| May | 1.46 | 0.83 | 0.64 | 1.95 | – | – |
| Jun | 1.61 | 0.99 | 0.69 | 2.29 | – | – |
| Jul | 1.61 | 1.07 | 0.79 | 2.51 | – | – |
| Aug | 1.49 | 0.95 | 0.74 | 2.33 | – | – |
| Sep | 1.24 | 0.72 | 0.6 | 1.86 | – | – |
| Oct | 0.87 | 0.47 | 0.46 | 1.33 | – | – |
| Nov | 0.47 | 0.22 | 0.33 | 0.9 | – | – |
| Dec | 0.31 | 0.14 | 0.26 | 0.68 | – | – |
| Year | 12 | 6.84 | 6.2 | 18.41 | – | – |
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 5
Rated low water in the Central Valley, like summer snowflake. Plants that drink alike can share one valve and one schedule.
Star of BethlehemOrnithogalum arabicumlow water, Central Valley1.07 gal/sq ft in July
Ivy Leaf CyclamenCyclamen hederifoliumlow water, Central Valley1.07 gal/sq ft in July
White Rain LilyZephyranthes candidalow water, Central Valley1.07 gal/sq ft in July
HyacinthHyacinthus spp.low water, Central Valley1.07 gal/sq ft in July
Sea SquillDrimia maritimalow water, Central Valley1.07 gal/sq ft in JulyTurn this into minutes on your water days
Every city page has a calculator that takes summer snowflake, 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 summer snowflake in summer?
In July, established summer snowflake needs about 0.8 gallons in the Central Valley, 0.6 gallons on the south coast and 1.8 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 summer snowflake need per day?
In July in the Central Valley, established summer snowflake 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 summer snowflake change across California?
Yes. WUCOLS rates summer snowflake separately for each of the six California climate zones: moderate water in the North-Central Coastal zone, low water in the Central Valley zone, low water in the South Coastal zone, moderate water 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.
Why is it called summer snowflake if it blooms in spring?
The name suggests summer, but the white, green-tipped bells open in mid-spring. By summer the plant is fading into dormancy. Water it while it is green, not after.
How deep should I plant summer snowflake?
Plant bulbs 2 to 4 inches deep and about 6 inches apart in fall. Water to settle them, then keep the soil moist once leaves appear. Leave them undisturbed afterward.
Does summer snowflake spread?
Yes, it spreads readily by offsets and can form drifts under trees or in lawns. It is considered invasive in Delaware, so keep it away from wild wetlands.
Are summer snowflake bulbs edible?
No, the bulbs are not edible. Store and plant them out of reach of children and pets that dig.
Can summer snowflake grow in wet soil?
Yes. It comes from seasonally damp places and tolerates wet and clay soils, though it prefers ground that drains. Avoid acidic soil.
More plant watering guides
Sources
- WUCOLS IV plant water use classification for Leucojum aestivum, 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