When to plant Arugula in Constantine, MI
For Arugula in Constantine, the safe spring window opens around April 14 and closes around May 5. Last expected frost is April 28, first fall frost October 16, giving a 171-day growing season. A second sowing from August 7 to August 21 extends the harvest into fall.
When to Plant Arugula in Constantine, MI
Your July gardening checklist
Here's what deserves your attention in St. Joseph County, Michigan this month. Everything below is tailored to Zone 6a and timed around your local frost dates.
-
Collect arugula at their peak
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
To set up a strong August, finish these tasks
- First harvests: arugula
- Fall sowing: 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.
Constantine, Michigan is in USDA Zone 6a. The average last spring frost is April 28 and the first fall frost is October 16, giving you a growing season of approximately 171 days.
At an elevation of 564 feet, St. Joseph County receives approximately 39.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Arugula to ensure they mature before fall.
Constantine Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.7
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 Constantine
How your county's soil matches Arugula's growing requirements.
Soil pH
Your soil pH (5.8–6.7) overlaps with Arugula's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in St. Joseph County is excellent for Arugula — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.2%) — Arugula will thrive.
How to Plant Arugula
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Arugula
Sow every 3.4 weeks. Last sowing by Aug 27 to harvest before frost.
For a dedicated fall crop, sow by Aug 07.
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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.9" | 0" | ❄️ Dormant |
| Apr | 2.6" | 3.7" | 0" | ✅ Rainfall sufficient |
| May | 2.6" | 5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.6" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 2.6" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.6" | 4.1" | 0" | ✅ Rainfall sufficient |
| Sep | 2.6" | 3.5" | 0" | ✅ Rainfall sufficient |
| Oct | 2.6" | 3" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in St. Joseph 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 — Constantine, MI
Arugula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 24 | Mar 24 – Apr 7 |
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
| Direct Sow | April 14 | Apr 14 – May 5 |
| Harvest | June 2 | Jun 2 – Aug 4 |
| Fall Sowing | August 7 | Aug 7 – Aug 21 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing 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 6a
📆 Growing Season
171 days in St. Joseph County
Growing Tips for Arugula in Constantine
Direct sow Arugula outdoors after April 28 in St. Joseph County when soil has warmed and frost danger has passed.
Your generous 171.0-day season in St. Joseph 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
When should I plant Arugula in Constantine, MI?
In Constantine, MI, plant Arugula after the last frost (around April 28) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is Constantine, MI for Arugula?
Constantine sits in USDA Zone 6a. Arugula grows reliably in zones 3a through 11b, so it's a good fit here.
Can Arugula grow in Constantine's climate?
Yes — Arugula grows well in Constantine's temperate climate. Constantine averages a 171-day frost-free season, with last frost around April 28 and first frost around October 16.
Your St. Joseph County Garden Planner — Free
A 22-page printable planner built for St. Joseph County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.