When to plant Leeks in Gray Summit, MO
For Gray Summit, gardeners: plant Leeks March 27 through April 17 once soil reads 50°F. A second sowing from August 18 to September 1 extends the harvest into fall.
When to Plant Leeks in Gray Summit, MO
July in Franklin County, Missouri — your action list
We've pulled the most time-sensitive tasks for Franklin County, Missouri this July and put them front and centre. Tackle them in order.
-
Basket week: leeks
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
Before August arrives, get these ready
- First harvests: leeks
- Fall sowing: leeks
Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.
Gray Summit, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 27, giving you a growing season of approximately 200 days.
At an elevation of 1,180 feet, Franklin County receives approximately 38.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Leeks during the growing season.
Gray Summit Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.8
Drainage
Well Drained
Leeks 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 Gray Summit
How your county's soil matches Leeks's growing requirements.
Soil pH
Your soil pH (5.7–6.8) overlaps with Leeks's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Franklin County is excellent for Leeks — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Leeks.
How to Plant Leeks
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Leeks Water Budget
Monthly Watering Guide for Leeks
Leeks needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.
| Month | Leeks Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.9" | 0" | ❄️ Dormant |
| Mar | — | 2.6" | 0" | ❄️ Dormant |
| Apr | 3.5" | 4" | 0" | ✅ Rainfall sufficient |
| May | 3.5" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jun | 3.5" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 4.7" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 3.5" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 3.2" | 0.3" | 💧 Light watering |
| Oct | 3.5" | 3.2" | 0.3" | 💧 Light watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Franklin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Leeks 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.
Leeks Planting Timeline — Gray Summit, MO
Leeks Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | April 10 | Apr 10 – Apr 24 |
| Direct Sow | March 27 | Mar 27 – Apr 17 |
| Harvest | July 10 | Jul 10 – Sep 25 |
| Fall Sowing | August 18 | Aug 18 – Sep 1 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Fall Sowing Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Natural rainfall sufficient
📅 Days to Maturity
90–150 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
200 days in Franklin County
Growing Tips for Leeks in Gray Summit
Direct sow Leeks outdoors after April 10 in Franklin County when soil has warmed and frost danger has passed.
Common pests for Leeks in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Leeks in Other Locations
When should I plant Leeks in Gray Summit, MO?
In Gray Summit, MO, plant Leeks after the last frost (around April 10) and before the first frost (around October 27). Best results when soil holds above 50°F.
What growing zone is Gray Summit, MO for Leeks?
Gray Summit sits in USDA Zone 6b. Leeks grows reliably in zones 3a through 10b, so it's a good fit here.
Can Leeks grow in Gray Summit's climate?
Yes — Leeks grows well in Gray Summit's temperate climate. Gray Summit averages a 200-day frost-free season, with last frost around April 10 and first frost around October 27.
Your Franklin County Garden Planner — Free
A 22-page printable planner built for Franklin County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.