When to Plant Spinach in Shasta County, CA
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.
Shasta County, California is in USDA Zone 8b. The average last spring frost is June 6 and the first fall frost is September 21, giving you a growing season of approximately 107 days.
At an elevation of 81 feet, Shasta County receives approximately 40.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 85°F, providing good warmth for Spinach during the growing season. Sandy soil warms quickly in spring — great for early planting — but Spinach will need more frequent watering and organic matter to retain nutrients.
Shasta County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.7-6.8
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 Shasta County
How your county's soil matches Spinach's growing requirements.
Soil pH
Your soil pH (5.7–6.8) is more acidic than Spinach prefers (6.5–7.5). Add garden lime to raise pH.
Soil Texture
Sandy soil in Shasta County warms quickly in spring but drains fast. Spinach will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Spinach.
How to Plant Spinach
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Spinach
Sow every 4 weeks. Last sowing by Aug 02 to harvest before frost.
For a dedicated fall crop, sow by Jul 13.
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 | — | 7.7" | 0" | ❄️ Dormant |
| Feb | — | 8" | 0" | ❄️ Dormant |
| Mar | — | 6.8" | 0" | ❄️ Dormant |
| Apr | — | 3.2" | 0" | ❄️ Dormant |
| May | — | 1" | 0" | ❄️ Dormant |
| 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 | — | 1.6" | 0" | ❄️ Dormant |
| Nov | — | 4.4" | 0" | ❄️ Dormant |
| Dec | — | 7.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Shasta 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 — Shasta County, CA
Spinach Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 2 | May 2 – May 16 |
| Transplant Outdoors | June 6 | Jun 6 – Jun 20 |
| Direct Sow | May 23 | May 23 – Jun 13 |
| Harvest | July 11 | Jul 11 – Sep 12 |
| Fall Sowing | July 13 | Jul 13 – Jul 27 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | Harvest |
| 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: too_acidic
🗺️ USDA Zone
Zone 8b
📆 Growing Season
107 days in Shasta County
Growing Tips for Spinach in Shasta County
Direct sow Spinach outdoors after June 06 in Shasta County when soil has warmed and frost danger has passed.
Sandy soil in Shasta County dries quickly — mulch Spinach with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
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 Shasta 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 Shasta County, CA?
Shasta County is in Zone 8b with an average last frost of June 6. Plan your Spinach planting based on this frost date — see the calendar above for exact timing.
What planting zone is Shasta County, CA?
Shasta County, California is in USDA Hardiness Zone 8b. The average last spring frost is June 6 and first fall frost is September 21.
Plan Your Garden with Confidence
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