When to Plant Kohlrabi in Rich County, UT
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.
Rich County, Utah is in USDA Zone 4b. The average last spring frost is May 31 and the first fall frost is September 15, giving you a growing season of approximately 107 days.
At an elevation of 5,803 feet, Rich County receives approximately 18 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Kohlrabi to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Kohlrabi successfully. Mulch heavily to conserve soil moisture.
Rich County Soil Profile
Soil Type
Loam
Soil pH
6.5-8.2
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 Rich County
How your county's soil matches Kohlrabi's growing requirements.
Soil pH
Your soil pH (6.5–8.2) overlaps with Kohlrabi's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Rich County is excellent for Kohlrabi — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.1%). Annual compost additions will help Kohlrabi.
How to Plant Kohlrabi
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Kohlrabi
Sow every 5.1 weeks. Last sowing by Jul 12 to harvest before frost.
For a dedicated fall crop, sow by Jun 23.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | — | 2" | 0" | ❄️ Dormant |
| May | 3" | 1.9" | 1.1" | 💧 Light watering |
| Jun | 3" | 1.4" | 1.6" | 🚿 Regular watering |
| Jul | 3" | 1.7" | 1.3" | 💧 Light watering |
| Aug | 3" | 1.7" | 1.3" | 💧 Light watering |
| Sep | 3" | 1.4" | 1.6" | 🚿 Regular watering |
| Oct | — | 1.6" | 0" | ❄️ Dormant |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Rich 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 — Rich County, UT
Kohlrabi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 19 | Apr 19 – May 3 |
| Transplant Outdoors | May 31 | May 31 – Jun 14 |
| Direct Sow | May 24 | May 24 – Jun 14 |
| Harvest | July 19 | Jul 19 – Aug 23 |
| Fall Sowing | June 23 | Jun 23 – Jul 7 |
Plant 0.5" deep · 4" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | — |
| 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 4b
📆 Growing Season
107 days in Rich County
Growing Tips for Kohlrabi in Rich County
Direct sow Kohlrabi outdoors after May 31 in Rich County when soil has warmed and frost danger has passed.
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
Frequently Asked Questions
When should I plant Kohlrabi in Rich County, UT?
Rich County is in Zone 4b with an average last frost of May 31. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rich County, UT?
Rich County, Utah is in USDA Hardiness Zone 4b. The average last spring frost is May 31 and first fall frost is September 15.
Plan Your Garden with Confidence
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