When to Plant Arugula in San Francisco County, CA
San Francisco County, California gardeners: here's your May plan
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in San Francisco County, California.
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Basket week: arugula
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
Get ahead of June
- First harvests: arugula
Arugula is a fast-growing cool-season green with a peppery, nutty flavor. It is excellent in salads and can be harvested as baby greens or mature leaves.
San Francisco County, California is in USDA Zone 10b. The average last spring frost is February 23 and the first fall frost is November 27, giving you a growing season of approximately 277 days.
At an elevation of 412 feet, San Francisco County receives approximately 13.5 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Arugula during the growing season. With low rainfall, drip irrigation is essential for growing Arugula successfully. Mulch heavily to conserve soil moisture.
San Francisco County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.2
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 Francisco County
How your county's soil matches Arugula's growing requirements.
Soil pH
Your soil pH (6.2–7.2) overlaps with Arugula's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in San Francisco County is excellent for Arugula — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.0%). Annual compost additions will help Arugula.
How to Plant Arugula
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Arugula
Sow every 3.4 weeks. Last sowing by Oct 08 to harvest before frost.
For a dedicated fall crop, sow by Oct 02.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Arugula
Arugula needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.
| Month | Arugula Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.3" | 0" | ❄️ Dormant |
| Feb | 2.6" | 3.1" | 0" | ✅ Rainfall sufficient |
| Mar | 2.6" | 2.2" | 0.4" | 💧 Light watering |
| Apr | 2.6" | 1.2" | 1.4" | 🚿 Regular watering |
| May | 2.6" | 0.3" | 2.3" | 🚿 Regular watering |
| Jun | 2.6" | 0.1" | 2.5" | 🚿 Regular watering |
| Jul | 2.6" | 0" | 2.6" | 🚿 Regular watering |
| Aug | 2.6" | 0" | 2.6" | 🚿 Regular watering |
| Sep | 2.6" | 0.1" | 2.5" | 🚿 Regular watering |
| Oct | 2.6" | 0.6" | 2" | 🚿 Regular watering |
| Nov | 2.6" | 1.4" | 1.2" | 💧 Light watering |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Feb–Nov in San Francisco County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Arugula 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.
Arugula Planting Timeline — San Francisco County, CA
Arugula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 26 | Jan 26 – Feb 9 |
| Transplant Outdoors | February 23 | Feb 23 – Mar 9 |
| Direct Sow | February 2 | Feb 2 – Feb 23 |
| Harvest | March 30 | Mar 30 – Jun 1 |
| Fall Sowing | October 2 | Oct 2 – Oct 16 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Harvest |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.6"/week · 1-2 times/week
📅 Days to Maturity
30–50 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 10b
📆 Growing Season
277 days in San Francisco County
Growing Tips for Arugula in San Francisco County
Direct sow Arugula outdoors after February 23 in San Francisco County when soil has warmed and frost danger has passed.
Your generous 278.0-day season in San Francisco County allows multiple plantings of Arugula. Sow every 15.0 days for continuous harvest.
Common pests for Arugula in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Sow seeds directly every 2-3 weeks for continuous harvest. Provide afternoon shade in warm weather to prevent bolting. Harvest outer leaves first to extend production.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Arugula in Other Locations
Frequently Asked Questions
When should I plant Arugula in San Francisco County, CA?
San Francisco County is in Zone 10b with an average last frost of February 23. Plan your Arugula planting based on this frost date — see the calendar above for exact timing.
What planting zone is San Francisco County, CA?
San Francisco County, California is in USDA Hardiness Zone 10b. The average last spring frost is February 23 and first fall frost is November 27.
Your San Francisco County Garden Planner — Free
A 24-page printable planner built for San Francisco County (Zone 10b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.