When to Plant Kohlrabi in Ruby, VA
Top priorities for Stafford County, Virginia gardeners in August
A quick August briefing for Stafford County, Virginia gardeners — what's urgent, what's next, and what can wait.
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Start your fall crops: kohlrabi
Count back from your first frost (November 4) — these need to mature before the cold arrives.
Kohlrabi is an unusual brassica that forms a swollen stem above ground with a mild, sweet turnip-like flavor. Both the bulb and tender leaves are edible.
Ruby, Virginia is in USDA Zone 7a. The average last spring frost is April 3 and the first fall frost is November 4, giving you a growing season of approximately 215 days.
At an elevation of 537 feet, Stafford County receives approximately 47 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Kohlrabi during the growing season.
Ruby Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.9
Drainage
Well Drained
Kohlrabi 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 Ruby
How your county's soil matches Kohlrabi's growing requirements.
Soil pH
Your soil pH (5.4–6.9) overlaps with Kohlrabi's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Stafford County is excellent for Kohlrabi — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Kohlrabi.
How to Plant Kohlrabi
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Kohlrabi
Sow every 5.1 weeks. Last sowing by Aug 31 to harvest before frost.
For a dedicated fall crop, sow by Aug 26.
Kohlrabi Water Budget
Monthly Watering Guide for Kohlrabi
Kohlrabi needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Kohlrabi Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.8" | 0" | ❄️ Dormant |
| Feb | — | 4" | 0" | ❄️ Dormant |
| Mar | — | 4.7" | 0" | ❄️ Dormant |
| Apr | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| May | 3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 5.3" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 2.9" | 0.1" | 💧 Light watering |
| Nov | 3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Stafford County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Kohlrabi 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.
Kohlrabi Planting Timeline — Ruby, VA
Kohlrabi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 27 | Feb 27 – Mar 13 |
| Transplant Outdoors | April 3 | Apr 3 – Apr 17 |
| Direct Sow | March 20 | Mar 20 – Apr 10 |
| Harvest | May 22 | May 22 – Jun 26 |
| Fall Sowing | August 26 | Aug 26 – Sep 9 |
Plant 0.5" deep · 4" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
45–65 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
215 days in Stafford County
Growing Tips for Kohlrabi in Ruby
Direct sow Kohlrabi outdoors after April 03 in Stafford County when soil has warmed and frost danger has passed.
Your generous 215.0-day season in Stafford County allows multiple plantings of Kohlrabi. Sow every 22.0 days for continuous harvest.
Common pests for Kohlrabi in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in spring or fall. Harvest when bulbs are 2-3 inches in diameter for best texture and flavor. Larger bulbs may become woody and fibrous.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Kohlrabi in Other Locations
Your Stafford County Garden Planner — Free
A 22-page printable planner built for Stafford 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.