How often to water cat thyme in California
In July in the Central Valley, established cat thyme in loam needs a deep watering about every 14 days: about 1.5 gallons each time for a plant 2 feet across, about 0.8 gallons a week. Cat thyme is a compact, bushy evergreen subshrub from the Mediterranean, about a foot tall and up to 2 feet wide. Tiny, aromatic, silvery gray-green leaves sit on downy white stems. Short spikes of tiny pink to purplish flowers appear in summer and fall. It is drought resistant and wants full sun and fast drainage.
How often to water cat thyme, 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: established roots fill the top 1 foot 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.
How to tell it needs water
- Cat thyme holding firm, silvery leaves through dry weather needs no extra water
- Stems flopping open or browning from the center after wet weather point to soggy soil
- A young plant wilting while the soil is dry an inch or two down needs a drink
- Leaves yellowing in a pot that sits in water point to overwatering
How to water it
- Water deeply but rarely, letting the soil dry well between drinks
- Plant in full sun in fast-draining, neutral to alkaline soil
- Give it a warm, sheltered spot, such as the foot of a sunny wall
- Trim it lightly after flowering to keep it compact
- Keep mulch thin and away from the stems
Through the seasons
Water a new plant until its roots settle in. Once established, it is drought resistant and needs little water. It stays evergreen, and flowers come in summer and fall. Winter rain covers its needs on the coast and in the Central Valley, so wet, heavy soil is the bigger winter risk. WUCOLS rates cat thyme low water on the north-central coast, in the Central Valley, on the south coast and in South Inland. WUCOLS has not evaluated it for the high desert or the low desert.
In pots
Cat thyme is small enough for a pot or trough on a sunny step. Use a gritty, free-draining mix. Water when the top couple of inches are dry, then let it drain through. In summer, check every few days. Keep the saucer empty. Trim lightly after bloom. In winter, water rarely and keep the pot out of steady rain, since cold, wet roots are its main risk.
- A year
- 6.84 gal per sq ft
- Reference
- Sacramento climate table
- Counts
- Plant need, before sprinkler losses
Monthly water need by climate zone
Cat Thyme: 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 | 0.31 | 0.31 | – | – |
| Feb | 0.21 | 0.26 | 0.32 | 0.35 | – | – |
| Mar | 0.35 | 0.43 | 0.46 | 0.52 | – | – |
| Apr | 0.47 | 0.61 | 0.56 | 0.64 | – | – |
| May | 0.58 | 0.83 | 0.64 | 0.78 | – | – |
| Jun | 0.64 | 0.99 | 0.69 | 0.92 | – | – |
| Jul | 0.64 | 1.07 | 0.79 | 1 | – | – |
| Aug | 0.6 | 0.95 | 0.74 | 0.93 | – | – |
| Sep | 0.5 | 0.72 | 0.6 | 0.74 | – | – |
| Oct | 0.35 | 0.47 | 0.46 | 0.53 | – | – |
| Nov | 0.19 | 0.22 | 0.33 | 0.36 | – | – |
| Dec | 0.12 | 0.14 | 0.26 | 0.27 | – | – |
| Year | 4.8 | 6.84 | 6.2 | 7.37 | – | – |
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 cat thyme. Plants that drink alike can share one valve and one schedule.
AgapanthusAgapanthus orientalislow water, Central Valley1.07 gal/sq ft in July
GeraniumsPelargonium x hortorum and cvs.low water, Central Valley1.07 gal/sq ft in July
SalviaSalvia greggii ssp., cvs. & hybridslow water, Central Valley1.07 gal/sq ft in July
IrisesIris germanicalow water, Central Valley1.07 gal/sq ft in July
SucculentsEcheveria spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
Russian SagePerovskia spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
YarrowAchillea millefolium (non-native hybrids)low water, Central Valley1.07 gal/sq ft in July
Mountain AlyssumAlyssum montanumlow water, Central Valley1.07 gal/sq ft in July
Silver SageSalvia argentealow water, Central Valley1.07 gal/sq ft in July
Purple MulleinVerbascum phoeniceumlow water, Central Valley1.07 gal/sq ft in July
Silvery YarrowAchillea clavennaelow water, Central Valley1.07 gal/sq ft in July
Fern Leaf YarrowAchillea filipendulinalow 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
Woolly YarrowAchillea tomentosalow water, Central Valley1.07 gal/sq ft in July
Perennial HollyhockAlcea rosea cvs.low water, Central Valley1.07 gal/sq ft in July
Mountain Lady's MantleAlchemilla alpinalow water, Central Valley1.07 gal/sq ft in JulyTurn this into minutes on your water days
Every city page has a calculator that takes cat thyme, 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 cat thyme in summer?
In July, established cat thyme in loam needs a deep watering about every 14 days in the Central Valley, about every 18 days on the south coast and about every 14 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 cat thyme need per day?
In July in the Central Valley, established cat thyme 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 cat thyme change across California?
Yes. WUCOLS rates cat thyme 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, 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.
Is cat thyme a real thyme?
No, it is a germander in the genus Teucrium, part of the mint family. Its small, aromatic leaves only look like thyme. It is harmful if eaten.
Does cat thyme need pruning?
Trim it back lightly after flowering. That keeps the plant compact. Remove any dead stems at the same time.
Where should I plant cat thyme?
Give it full sun and a sheltered, warm spot. Gravel gardens, rock gardens and wall edges suit it. Good drainage is essential.
When does cat thyme bloom?
Short spikes of tiny pink to purplish blooms open from summer into fall. The flowers are small. Most people grow it for the silvery leaves.
How big does cat thyme get?
It grows about a foot tall and 1 to 2 feet wide. It stays compact and bushy. Space plants so air moves between them.
More plant watering guides
Sources
- WUCOLS IV plant water use classification for Teucrium marum, 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