When to Plant Alpine Strawberries in San Mateo County, CA
This month in San Mateo County, California
A quick May briefing for San Mateo County, California gardeners — what's urgent, what's next, and what can wait.
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Harvest alpine strawberries as they ripen
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Before June arrives, get these ready
- First harvests: alpine strawberries
Alpine strawberries are small, intensely flavored wild-type strawberries that fruit continuously from spring to frost. They do not produce runners and make excellent edging plants.
San Mateo County, California is in USDA Zone 10a. The average last spring frost is January 18 and the first fall frost is December 12, giving you a growing season of approximately 328 days.
At an elevation of 277 feet, San Mateo County receives approximately 16.9 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Alpine Strawberries to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Alpine Strawberries successfully. Mulch heavily to conserve soil moisture.
San Mateo County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.2
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in San Mateo County
How your county's soil matches Alpine Strawberries's growing requirements.
Soil pH
Your soil pH (6.8–7.2) is more alkaline than Alpine Strawberries prefers (5.5–6.8). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in San Mateo County is excellent for Alpine Strawberries — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Alpine Strawberries.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Alpine Strawberries.
How to Plant Alpine Strawberries
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Alpine Strawberries
Alpine Strawberries needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Alpine Strawberries Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Feb | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Mar | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Apr | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| May | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Jun | 4.3" | 0.1" | 4.2" | 🚿 Regular watering |
| Jul | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Aug | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Sep | 4.3" | 0.2" | 4.1" | 🚿 Regular watering |
| Oct | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Nov | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Dec | 4.3" | 2.9" | 1.4" | 💧 Light watering |
Water needs are for active growing months only (Jan–Dec in San Mateo County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Alpine Strawberries Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Alpine Strawberries Planting Timeline — San Mateo County, CA
Alpine Strawberries Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | February 1 | Feb 1 – Feb 15 |
| Harvest | May 3 | May 3 – Aug 16 |
· 12" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Transplant Outdoors |
| March | — |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
90–180 days
🧪 Soil pH
Needs 5.5–6.8 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 10a
📆 Growing Season
328 days in San Mateo County
Growing Tips for Alpine Strawberries in San Mateo County
Direct sow Alpine Strawberries outdoors after January 18 in San Mateo County when soil has warmed and frost danger has passed.
San Mateo County receives only 17" of rain annually. Alpine Strawberries needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 8-10 weeks before transplanting. Unlike regular strawberries, alpines do not spread by runners. Harvest tiny, intensely aromatic berries frequently. Grow well in partial shade.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Alpine Strawberries in Other Locations
Frequently Asked Questions
When should I plant Alpine Strawberries in San Mateo County, CA?
San Mateo County is in Zone 10a with an average last frost of January 18. Plan your Alpine Strawberries planting based on this frost date — see the calendar above for exact timing.
What planting zone is San Mateo County, CA?
San Mateo County, California is in USDA Hardiness Zone 10a. The average last spring frost is January 18 and first fall frost is December 12.
Your San Mateo County Garden Planner — Free
A 24-page printable planner built for San Mateo County (Zone 10a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.