When to Plant Tomatoes in Gregory County, SD
Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.
Gregory County, South Dakota is in USDA Zone 5a. The average last spring frost is May 10 and the first fall frost is October 6, giving you a growing season of approximately 149 days.
At an elevation of 668 feet, Gregory County receives approximately 34.5 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Tomatoes to ensure they mature before fall.
Gregory County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
How Much Tomatoes to Grow
For a family of 4, plant approximately 12 tomatoes plants in about 24 sq ft. In Gregory County's 149-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Tomatoes Planting Timeline — Gregory County, SD
Tomatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 15 | Mar 15 – Mar 29 |
| Transplant Outdoors | May 24 | May 24 – Jun 7 |
| Direct Sow | May 17 | May 17 – Jun 7 |
| Harvest | July 26 | Jul 26 – Oct 4 |
Plant 0.5" deep · 24" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
60–85 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
149 days in Gregory County
Growing Tips for Gregory County
Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.
Tomatoes in Other Locations
Frequently Asked Questions
When should I plant Tomatoes in Gregory County, SD?
Gregory County is in Zone 5a with an average last frost of May 10. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Gregory County, SD?
Gregory County, South Dakota is in USDA Hardiness Zone 5a. The average last spring frost is May 10 and first fall frost is October 6.
Your Gregory County Garden Planner — Free
A 22-page printable planner built for Gregory 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.