When to plant Arugula in Cass County, MN
Cass County gardeners should plant Arugula between May 5 and May 26 in spring. With Cass County's Zone 4a climate (last frost May 12), Arugula needs 30–50 days to mature — plant by August 9 for a full harvest. A second sowing from July 6 to July 20 extends the harvest into fall.
When to Plant Arugula in Cass County, MN
July in Cass County, Minnesota — your action list
July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Cass County, Minnesota.
-
Collect arugula at their peak
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
-
Get arugula in for a late-season harvest
Your first frost is about 10 weeks away — plenty of time for these to mature.
Coming up in August — start thinking about
- First harvests: arugula
Arugula is a fast-growing cool-season green with a peppery, nutty flavor. It is excellent in salads and can be harvested as baby greens or mature leaves.
Cass County, Minnesota is in USDA Zone 4a. The average last spring frost is May 12 and the first fall frost is September 28, giving you a growing season of approximately 139 days.
At an elevation of 938 feet, Cass County receives approximately 32.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Arugula to ensure they mature before fall.
Cass County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.9
Drainage
Well Drained
Arugula 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 Cass County
How your county's soil matches Arugula's growing requirements.
Soil pH
Your soil pH (5.9–6.9) overlaps with Arugula's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Cass County is excellent for Arugula — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.6%) — Arugula will thrive.
How to Plant Arugula
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Arugula
Sow every 3.4 weeks. Last sowing by Aug 09 to harvest before frost.
For a dedicated fall crop, sow by Jul 06.
Arugula Water Budget
Monthly Watering Guide for Arugula
Arugula needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.
| Month | Arugula Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | — | 3" | 0" | ❄️ Dormant |
| May | 2.6" | 3.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.6" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jul | 2.6" | 3.8" | 0" | ✅ Rainfall sufficient |
| Aug | 2.6" | 3.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.6" | 3.2" | 0" | ✅ Rainfall sufficient |
| Oct | — | 2.5" | 0" | ❄️ Dormant |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Cass County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Arugula 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.
Arugula Planting Timeline — Cass County, MN
Arugula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 31 | Mar 31 – Apr 14 |
| Transplant Outdoors | May 12 | May 12 – May 26 |
| Direct Sow | May 5 | May 5 – May 26 |
| Harvest | June 16 | Jun 16 – Aug 18 |
| Fall Sowing | July 6 | Jul 6 – Jul 20 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.6"/week · Natural rainfall sufficient
📅 Days to Maturity
30–50 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 4a
📆 Growing Season
139 days in Cass County
Growing Tips for Arugula in Cass County
Direct sow Arugula outdoors after May 12 in Cass County when soil has warmed and frost danger has passed.
Your generous 139.0-day season in Cass County allows multiple plantings of Arugula. Sow every 15.0 days for continuous harvest.
Common pests for Arugula in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Sow seeds directly every 2-3 weeks for continuous harvest. Provide afternoon shade in warm weather to prevent bolting. Harvest outer leaves first to extend production.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Arugula in Other Locations
Frequently Asked Questions
When should I plant Arugula in Cass County, MN?
Cass County is in Zone 4a with an average last frost of May 12. Plan your Arugula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cass County, MN?
Cass County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 12 and first fall frost is September 28.
When should I plant Arugula in Cass County, MN?
In Cass County, MN, plant Arugula after the last frost (around May 12) and before the first frost (around September 28). Best results when soil holds above 50°F.
What growing zone is Cass County, MN for Arugula?
Cass County sits in USDA Zone 4a. Arugula grows reliably in zones 3a through 11b, so it's a good fit here.
Can Arugula grow in Cass County's climate?
Yes — Arugula grows well in Cass County's temperate climate. Cass County averages a 139-day frost-free season, with last frost around May 12 and first frost around September 28.
Your Cass County Garden Planner — Free
A 22-page printable planner built for Cass County (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.