When to Plant Spinach in Tuolumne County, CA
Tuolumne County, California gardeners: here's your May plan
Welcome to May in Zone 9b. These are the moves that will have the biggest impact on your growing season.
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Sow spinach in trays indoors
These need a head start before your last frost (April 25). Sow into cells now so you're ready to transplant in a few weeks.
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Basket week: spinach
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
June prep starts now
- First harvests: spinach
Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.
Tuolumne County, California is in USDA Zone 9b. The average last spring frost is April 25 and the first fall frost is October 27, giving you a growing season of approximately 185 days.
At an elevation of 2,990 feet, Tuolumne County receives approximately 37.7 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Spinach during the growing season.
Tuolumne County Soil Profile
Soil Type
Loam
Soil pH
6.6-7.5
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 Tuolumne County
How your county's soil matches Spinach's growing requirements.
Soil pH
Your soil pH (6.6–7.5) is within Spinach's preferred range (6.5–7.5).
Soil Texture
The loam soil in Tuolumne County is excellent for Spinach — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). Annual compost additions will help Spinach.
How to Plant Spinach
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Spinach
Sow every 4 weeks. Last sowing by Sep 07 to harvest before frost.
For a dedicated fall crop, sow by Sep 01.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Spinach
Spinach needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Spinach Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 7.8" | 0" | ❄️ Dormant |
| Feb | — | 8.2" | 0" | ❄️ Dormant |
| Mar | — | 6.7" | 0" | ❄️ Dormant |
| Apr | 3" | 2.8" | 0.2" | 💧 Light watering |
| May | 3" | 1.1" | 1.9" | 🚿 Regular watering |
| Jun | 3" | 0.2" | 2.8" | 🚿 Regular watering |
| Jul | 3" | 0" | 3" | 🚿 Regular watering |
| Aug | 3" | 0" | 3" | 🚿 Regular watering |
| Sep | 3" | 0.4" | 2.6" | 🚿 Regular watering |
| Oct | 3" | 1.5" | 1.5" | 🚿 Regular watering |
| Nov | — | 3" | 0" | ❄️ Dormant |
| Dec | — | 6.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Tuolumne County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Spinach 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.
Spinach Planting Timeline — Tuolumne County, CA
Spinach Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 28 | Mar 28 – Apr 11 |
| Transplant Outdoors | April 25 | Apr 25 – May 9 |
| Direct Sow | April 4 | Apr 4 – Apr 25 |
| Harvest | May 30 | May 30 – Aug 1 |
| Fall Sowing | September 1 | Sep 1 – Sep 15 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Harvest |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
35–50 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 9b
📆 Growing Season
185 days in Tuolumne County
Growing Tips for Spinach in Tuolumne County
Direct sow Spinach outdoors after April 25 in Tuolumne County when soil has warmed and frost danger has passed.
Your generous 185.0-day season in Tuolumne County allows multiple plantings of Spinach. Sow every 17.0 days for continuous harvest.
General growing tips
Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.
Recommended Spinach Varieties for Tuolumne County
Slow-bolting spinach for warm springs — best as fall crop here
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Wind pollinated — isolate 1/2 mile for purity. Easy to let bolt in heat.
Spinach in Other Locations
Frequently Asked Questions
When should I plant Spinach in Tuolumne County, CA?
Tuolumne County is in Zone 9b with an average last frost of April 25. Plan your Spinach planting based on this frost date — see the calendar above for exact timing.
What planting zone is Tuolumne County, CA?
Tuolumne County, California is in USDA Hardiness Zone 9b. The average last spring frost is April 25 and first fall frost is October 27.
Your Tuolumne County Garden Planner — Free
A 24-page printable planner built for Tuolumne 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.