When to Plant Turnip in Sac County, IA
Sac County, Iowa gardeners: here's your May plan
May is a pivotal month for Sac County, Iowa gardens. Focus on these tasks first and you'll set up the rest of the season for success.
-
Harvest turnip as they ripen
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
June will be here before you know it — start on
- First harvests: turnip
Turnips are a fast-growing cool-season root vegetable with edible roots and greens. Baby turnips are sweet and tender while mature ones are more pungent.
Sac County, Iowa is in USDA Zone 5a. The average last spring frost is April 25 and the first fall frost is October 8, giving you a growing season of approximately 166 days.
At an elevation of 1,221 feet, Sac County receives approximately 31.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Turnip to ensure they mature before fall.
Sac County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.7
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 Sac County
How your county's soil matches Turnip's growing requirements.
Soil pH
Your soil pH (5.9–6.7) overlaps with Turnip's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Sac County is excellent for Turnip — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.8%) — Turnip will thrive.
How to Plant Turnip
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Turnip
Sow every 4.6 weeks. Last sowing by Aug 09 to harvest before frost.
For a dedicated fall crop, sow by Jul 30.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Turnip
Turnip needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Turnip Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| May | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Jun | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Jul | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Aug | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Sep | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Oct | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Sac County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Turnip 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.
Turnip Planting Timeline — Sac County, IA
Turnip Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 11 | Apr 11 – May 2 |
| Harvest | May 23 | May 23 – Jun 27 |
| Fall Sowing | July 30 | Jul 30 – Aug 13 |
Plant 0.5" deep · 4" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Direct Sow |
| May | Direct Sow Harvest |
| June | Harvest |
| July | Fall Sowing |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
166 days in Sac County
Growing Tips for Turnip in Sac County
Direct sow Turnip outdoors after April 25 in Sac County when soil has warmed and frost danger has passed.
Your generous 166.0-day season in Sac County allows multiple plantings of Turnip. Sow every 20.0 days for continuous harvest.
Common pests for Turnip 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 early spring or late summer. Harvest when roots are 2-3 inches in diameter for best flavor. Both the roots and the greens are nutritious and edible.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Turnip in Other Locations
Frequently Asked Questions
When should I plant Turnip in Sac County, IA?
Sac County is in Zone 5a with an average last frost of April 25. Plan your Turnip planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sac County, IA?
Sac County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 25 and first fall frost is October 8.
Your Sac County Garden Planner — Free
A 24-page printable planner built for Sac County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.