When to Plant Parsley in Marin County, CA
Top priorities for Marin County, California gardeners in May
Here's what deserves your attention in Marin County, California this month. Everything below is tailored to Zone 9b and timed around your local frost dates.
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Start harvesting parsley
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
A few tasks this May that'll pay off in June
- First harvests: parsley
Parsley is a biennial herb available in flat-leaf (Italian) and curly varieties. It is a nutritional powerhouse rich in vitamins C and K and adds fresh flavor to countless dishes.
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 Parsley to ensure they mature before fall. Sandy soil warms quickly in spring — great for early planting — but Parsley will need more frequent watering and organic matter to retain nutrients.
Marin County Soil Profile
Soil Type
Sandy Loam
Soil pH
6-6.9
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 Marin County
How your county's soil matches Parsley's growing requirements.
Soil pH
Your soil pH (6.0–6.9) is within Parsley's preferred range (6.0–7.0).
Soil Texture
Sandy soil in Marin County warms quickly in spring but drains fast. Parsley 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 Parsley.
How to Plant Parsley
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Parsley
Sow every 6.9 weeks. Last sowing by Sep 07 to harvest before frost.
For a dedicated fall crop, sow by Oct 01.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Parsley
Parsley 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 | Parsley Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 7.2" | 0" | ❄️ Dormant |
| Feb | 2.6" | 6.5" | 0" | ✅ Rainfall sufficient |
| Mar | 2.6" | 6.2" | 0" | ✅ Rainfall sufficient |
| Apr | 2.6" | 2.7" | 0" | ✅ Rainfall sufficient |
| May | 2.6" | 1" | 1.6" | 🚿 Regular watering |
| Jun | 2.6" | 0.2" | 2.4" | 🚿 Regular watering |
| Jul | 2.6" | 0" | 2.6" | 🚿 Regular watering |
| Aug | 2.6" | 0" | 2.6" | 🚿 Regular watering |
| Sep | 2.6" | 0.4" | 2.2" | 🚿 Regular watering |
| Oct | 2.6" | 1.4" | 1.2" | 💧 Light watering |
| Nov | 2.6" | 3.5" | 0" | ✅ Rainfall sufficient |
| 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.
Parsley 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.
Parsley Planting Timeline — Marin County, CA
Parsley Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 29 | Jan 29 – Feb 12 |
| Transplant Outdoors | February 19 | Feb 19 – Mar 5 |
| Direct Sow | February 5 | Feb 5 – Feb 26 |
| Harvest | April 23 | Apr 23 – Jun 25 |
| Fall Sowing | October 1 | Oct 1 – Oct 15 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Transplant Outdoors |
| 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 · Only during dry spells
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 9b
📆 Growing Season
273 days in Marin County
Growing Tips for Parsley in Marin County
Direct sow Parsley outdoors after February 26 in Marin County when soil has warmed and frost danger has passed.
Sandy soil in Marin County dries quickly — mulch Parsley with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Parsley in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Soak seeds overnight as germination is slow. Harvest outer stems first to keep plants productive. Parsley attracts swallowtail butterflies.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Parsley in Other Locations
Frequently Asked Questions
When should I plant Parsley in Marin County, CA?
Marin County is in Zone 9b with an average last frost of February 26. Plan your Parsley 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.