When to Plant Spinach in Klamath County, OR
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.
Klamath County, Oregon is in USDA Zone 6a. The average last spring frost is June 13 and the first fall frost is September 21, giving you a growing season of approximately 100 days.
At an elevation of 142 feet, Klamath County receives approximately 48.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Spinach to ensure they mature before fall.
Klamath County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.3
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 Klamath County
How your county's soil matches Spinach's growing requirements.
Soil pH
Your soil pH (5.5–6.3) is more acidic than Spinach prefers (6.5–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Klamath County is excellent for Spinach — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Spinach.
Organic Matter
Organic matter is excellent (5.1%) — Spinach will thrive.
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
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 | — | 7.4" | 0" | ❄️ Dormant |
| Feb | — | 5.2" | 0" | ❄️ Dormant |
| Mar | — | 4.8" | 0" | ❄️ Dormant |
| Apr | — | 3.3" | 0" | ❄️ Dormant |
| May | — | 3" | 0" | ❄️ Dormant |
| Jun | 3" | 1.8" | 1.2" | 💧 Light watering |
| Jul | 3" | 0.9" | 2.1" | 🚿 Regular watering |
| Aug | 3" | 0.8" | 2.2" | 🚿 Regular watering |
| Sep | 3" | 2.1" | 0.9" | 💧 Light watering |
| Oct | — | 4.8" | 0" | ❄️ Dormant |
| Nov | — | 7.7" | 0" | ❄️ Dormant |
| Dec | — | 6.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Klamath 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 — Klamath County, OR
Spinach Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 9 | May 9 – May 23 |
| Transplant Outdoors | June 13 | Jun 13 – Jun 27 |
| Direct Sow | May 30 | May 30 – Jun 20 |
| Harvest | July 18 | Jul 18 – Sep 19 |
| 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 6a
📆 Growing Season
100 days in Klamath County
Growing Tips for Spinach in Klamath County
Direct sow Spinach outdoors after June 13 in Klamath County when soil has warmed and frost danger has passed.
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.
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 Klamath County, OR?
Klamath County is in Zone 6a with an average last frost of June 13. Plan your Spinach planting based on this frost date — see the calendar above for exact timing.
What planting zone is Klamath County, OR?
Klamath County, Oregon is in USDA Hardiness Zone 6a. The average last spring frost is June 13 and first fall frost is September 21.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Klamath County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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