When to Plant Zucchini in Solano County, CA
May in the garden — Solano County, California
We've pulled the most time-sensitive tasks for Solano County, California this May and put them front and centre. Tackle them in order.
-
Basket week: zucchini
If you can't use it all right away, check the food-preservation section of your planner.
Before June arrives, get these ready
- First harvests: zucchini
Zucchini is an incredibly prolific summer squash that can produce an abundance of fruit from just a few plants. It is versatile in the kitchen from grilling to baking.
Solano County, California is in USDA Zone 9b. The average last spring frost is February 9 and the first fall frost is December 3, giving you a growing season of approximately 297 days.
At an elevation of 376 feet, Solano County receives approximately 40.4 inches of rainfall annually with predominantly loam soil. Summer highs average 95°F, so Zucchini may need afternoon shade and extra watering during peak heat.
Solano County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.3
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 Solano County
How your county's soil matches Zucchini's growing requirements.
Soil pH
Your soil pH (6.8–7.3) is within Zucchini's preferred range (6.0–7.5).
Soil Texture
The loam soil in Solano County is excellent for Zucchini — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Zucchini.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Zucchini.
How to Plant Zucchini
Succession Planting Zucchini
Sow every 5.1 weeks. Last sowing by Oct 04 to harvest before frost.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Zucchini
Zucchini needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.
| Month | Zucchini Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 8.9" | 0" | ❄️ Dormant |
| Feb | 5.2" | 8.4" | 0" | ✅ Rainfall sufficient |
| Mar | 5.2" | 6.6" | 0" | ✅ Rainfall sufficient |
| Apr | 5.2" | 2.7" | 2.5" | 💧 Light watering |
| May | 5.2" | 1" | 4.2" | 🚿 Regular watering |
| Jun | 5.2" | 0.2" | 5" | 🚿 Regular watering |
| Jul | 5.2" | 0" | 5.2" | 🚿 Regular watering |
| Aug | 5.2" | 0" | 5.2" | 🚿 Regular watering |
| Sep | 5.2" | 0.4" | 4.8" | 🚿 Regular watering |
| Oct | 5.2" | 1.9" | 3.3" | 🚿 Regular watering |
| Nov | 5.2" | 3.3" | 1.9" | 💧 Light watering |
| Dec | 5.2" | 7.1" | 0" | ✅ Rainfall sufficient |
Water needs are for active growing months only (Feb–Dec in Solano County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Zucchini 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.
Zucchini Planting Timeline — Solano County, CA
Zucchini Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 12 | Jan 12 – Jan 26 |
| Transplant Outdoors | February 16 | Feb 16 – Mar 2 |
| Direct Sow | February 9 | Feb 9 – Mar 2 |
| Harvest | April 6 | Apr 6 – Jun 1 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.2"/week · 2-3 times/week
📅 Days to Maturity
45–60 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 9b
📆 Growing Season
297 days in Solano County
Growing Tips for Zucchini in Solano County
Direct sow Zucchini outdoors after February 09 in Solano County when soil has warmed and frost danger has passed.
Your generous 298.0-day season in Solano County allows multiple plantings of Zucchini. Sow every 22.0 days for continuous harvest.
Common pests for Zucchini in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow after last frost. Harvest when fruits are 6-8 inches long for best flavor and texture. Check plants daily in summer as fruits can double in size overnight.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Zucchini in Other Locations
Frequently Asked Questions
When should I plant Zucchini in Solano County, CA?
Solano County is in Zone 9b with an average last frost of February 9. Plan your Zucchini planting based on this frost date — see the calendar above for exact timing.
What planting zone is Solano County, CA?
Solano County, California is in USDA Hardiness Zone 9b. The average last spring frost is February 9 and first fall frost is December 3.
Your Solano County Garden Planner — Free
A 24-page printable planner built for Solano 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.