When to plant Thai Basil in Rock County, MN
Rock County sits in USDA Zone 5a. Plant Thai Basil between May 9 (after last frost on May 2) and May 30.
When to Plant Thai Basil in Rock County, MN
Your June planting checklist for Rock County, Minnesota
A quick June briefing for Rock County, Minnesota gardeners — what's urgent, what's next, and what can wait.
Thai basil has a distinctive anise-licorice flavor with sturdy purple stems and small leaves. It is essential in Thai, Vietnamese, and other Southeast Asian cuisines.
Rock County, Minnesota is in USDA Zone 5a. The average last spring frost is May 2 and the first fall frost is October 2, giving you a growing season of approximately 153 days.
At an elevation of 916 feet, Rock County receives approximately 32.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Thai Basil to ensure they mature before fall.
Rock County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.9
Drainage
Well Drained
Thai Basil 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 Rock County
How your county's soil matches Thai Basil's growing requirements.
Soil pH
Your soil pH (5.7–6.9) overlaps with Thai Basil's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Rock County is excellent for Thai Basil — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.1%) — Thai Basil will thrive.
How to Plant Thai Basil
Succession Planting Thai Basil
Sow every 5.7 weeks. Last sowing by Jul 19 to harvest before frost.
Thai Basil Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Thai Basil
Thai Basil needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Thai Basil Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.2" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | — | 2.9" | 0" | ❄️ Dormant |
| May | 4.3" | 3.3" | 1" | 💧 Light watering |
| Jun | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Jul | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Aug | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Sep | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Oct | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 1.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Rock County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Thai Basil 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.
Thai Basil Planting Timeline — Rock County, MN
Thai Basil Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 14 | Mar 14 – Mar 28 |
| Transplant Outdoors | May 16 | May 16 – May 30 |
| Direct Sow | May 9 | May 9 – May 30 |
| Harvest | July 11 | Jul 11 – Sep 12 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
50–75 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
153 days in Rock County
Growing Tips for Thai Basil in Rock County
Direct sow Thai Basil outdoors after May 02 in Rock County when soil has warmed and frost danger has passed.
General growing tips
Start seeds indoors or direct sow after last frost. Thai basil holds up better to heat in cooking than sweet basil. Pinch flowers to prolong leaf production.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Thai Basil in Other Locations
Frequently Asked Questions
When should I plant Thai Basil in Rock County, MN?
Rock County is in Zone 5a with an average last frost of May 2. Plan your Thai Basil planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rock County, MN?
Rock County, Minnesota is in USDA Hardiness Zone 5a. The average last spring frost is May 2 and first fall frost is October 2.
When should I plant Thai Basil in Rock County, MN?
In Rock County, MN, plant Thai Basil after the last frost (around May 2) and before the first frost (around October 2). Best results when soil holds above 50°F.
What growing zone is Rock County, MN for Thai Basil?
Rock County sits in USDA Zone 5a. Thai Basil grows reliably in zones 4a through 11b, so it's a good fit here.
Can Thai Basil grow in Rock County's climate?
Yes — Thai Basil grows well in Rock County's temperate climate. Rock County averages a 153-day frost-free season, with last frost around May 2 and first frost around October 2.
Your Rock County Garden Planner — Free
A 22-page printable planner built for Rock 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.