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When to Plant Alpine Strawberries in Marin County, CA

Marin County, California Zone 9b May

What to do in May

May is a pivotal month for Marin County, California gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost February 26
Avg. first frost November 26
Soil temp (4") 79°F
Watering Critical
Pest pressure High
Daylight 14.1 hrs
June will be here before you know it — start on
  • First harvests: alpine strawberries

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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.

Marin County, California is in USDA Zone 9b. The average last spring frost is February 26 and the first fall frost is November 26, giving you a growing season of approximately 273 days.

At an elevation of 302 feet, Marin County receives approximately 36 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 81°F, so choose short-season varieties of Alpine Strawberries to ensure they mature before fall. Sandy soil warms quickly in spring — great for early planting — but Alpine Strawberries will need more frequent watering and organic matter to retain nutrients.

Marin County, CA (Zone 9b) Year-round
273 days
Last Spring Frost February 26
273 growing days
First Fall Frost November 26

Marin County Soil Profile

Soil Type

Sandy Loam

Soil pH

6-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (75 days to spare)
Transplant: Feb 24 🍅 Harvest: May 26 – Sep 8
Recommended (50%) ✓ Fits season (63 days to spare)
Transplant: Mar 12 🍅 Harvest: Jun 11 – Sep 24
Safe Start (90%) ✓ Fits season (49 days to spare)
Transplant: Apr 16 🍅 Harvest: Jul 16 – Oct 29

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 Marin County

How your county's soil matches Alpine Strawberries's growing requirements.

Soil pH

Your soil pH (6.0–6.9) overlaps with Alpine Strawberries's range (5.5–6.8), though not a perfect match.

Soil Texture

Sandy soil in Marin County warms quickly in spring but drains fast. Alpine Strawberries will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Alpine Strawberries.

How to Plant Alpine Strawberries

12"
Between Plants
24"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 1,312 gal / 100 sq ft
Drought risk

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 7.2" 0" ❄️ Dormant
Feb 4.3" 6.5" 0" ✅ Rainfall sufficient
Mar 4.3" 6.2" 0" ✅ Rainfall sufficient
Apr 4.3" 2.7" 1.6" 💧 Light watering
May 4.3" 1" 3.3" 🚿 Regular watering
Jun 4.3" 0.2" 4.1" 🚿 Regular watering
Jul 4.3" 0" 4.3" 🚿 Regular watering
Aug 4.3" 0" 4.3" 🚿 Regular watering
Sep 4.3" 0.4" 3.9" 🚿 Regular watering
Oct 4.3" 1.4" 2.9" 🚿 Regular watering
Nov 4.3" 3.5" 0.8" 💧 Light watering
Dec 6.9" 0" ❄️ Dormant

Water needs are for active growing months only (Feb–Nov in Marin 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 needs ~1,451 GDD — county provides 2,945 GDD Excellent fit

Alpine Strawberries Planting Timeline — Marin County, CA

Alpine Strawberries Planting Calendar

Activity When Date Range
Transplant Outdoors March 12 Mar 12 – Mar 26
Harvest June 11 Jun 11 – Sep 24

· 12" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March Transplant Outdoors
April
May
June Harvest
July Harvest
August Harvest
September Harvest
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

90–180 days

🧪 Soil pH

Needs 5.5–6.8 · Your soil: acceptable

🗺️ USDA Zone

Zone 9b

📆 Growing Season

273 days in Marin County

Growing Tips for Alpine Strawberries in Marin County

Direct sow Alpine Strawberries outdoors after February 26 in Marin County when soil has warmed and frost danger has passed.

Sandy soil in Marin County dries quickly — mulch Alpine Strawberries with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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

  • Cabbage

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Alpine Strawberries in Marin County, CA?

Marin County is in Zone 9b with an average last frost of February 26. Plan your Alpine Strawberries planting based on this frost date — see the calendar above for exact timing.

What planting zone is Marin County, CA?

Marin County, California is in USDA Hardiness Zone 9b. The average last spring frost is February 26 and first fall frost is November 26.

🌱

Your Marin County Garden Planner — Free

A 24-page printable planner built for Marin County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Marin County, CA. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.