When to plant Spinach in Ballwin, MO
In Zone 7a (Ballwin), direct-sow Spinach between March 30 and April 20 for spring, after the April 13 last-frost mark. A second sowing from August 15 to August 29 extends the harvest into fall.
When to Plant Spinach in Ballwin, MO
July in St. Louis County, Missouri — your action list
July is a pivotal month for St. Louis County, Missouri gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Harvest spinach as they ripen
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
A few tasks this July that'll pay off in August
- Fall sowing: 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.
Ballwin, Missouri is in USDA Zone 7a. The average last spring frost is April 13 and the first fall frost is October 24, giving you a growing season of approximately 194 days.
At an elevation of 895 feet, St. Louis County receives approximately 40.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Spinach during the growing season.
Ballwin Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.6
Drainage
Well Drained
Spinach 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 Ballwin
How your county's soil matches Spinach's growing requirements.
Soil pH
Your soil pH (5.4–6.6) is more acidic than Spinach prefers (6.5–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in St. Louis County is excellent for Spinach — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.0%). 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 Sep 04 to harvest before frost.
For a dedicated fall crop, sow by Aug 15.
Spinach 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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.8" | 0" | ❄️ Dormant |
| Apr | 3" | 3.7" | 0" | ✅ Rainfall sufficient |
| May | 3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.4" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in St. Louis 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 — Ballwin, MO
Spinach Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 9 | Mar 9 – Mar 23 |
| Transplant Outdoors | April 13 | Apr 13 – Apr 27 |
| Direct Sow | March 30 | Mar 30 – Apr 20 |
| Harvest | May 18 | May 18 – Jul 20 |
| Fall Sowing | August 15 | Aug 15 – Aug 29 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| 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 7a
📆 Growing Season
194 days in St. Louis County
Growing Tips for Spinach in Ballwin
Direct sow Spinach outdoors after April 13 in St. Louis County when soil has warmed and frost danger has passed.
Your generous 194.0-day season in St. Louis 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 Ballwin
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
When should I plant Spinach in Ballwin, MO?
In Ballwin, MO, plant Spinach after the last frost (around April 13) and before the first frost (around October 24). Best results when soil holds above 50°F.
What growing zone is Ballwin, MO for Spinach?
Ballwin sits in USDA Zone 7a. Spinach grows reliably in zones 2a through 10b, so it's a good fit here.
Can Spinach grow in Ballwin's climate?
Yes — Spinach grows well in Ballwin's temperate climate. Ballwin averages a 194-day frost-free season, with last frost around April 13 and first frost around October 24.
Your St. Louis County Garden Planner — Free
A 22-page printable planner built for St. Louis County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.