Missouri · zones 5b–7a
When to plant tomatoes in Missouri.
Sow or transplant between Apr 22 to Jun 22 in a typical year, keyed to Missouri's median last frost around Apr 15. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Tomatoes dates for a typical Missouri season.
1 · Start indoors
Mar 11 to May 11
About 6 weeks before set-out. Warm spot, real light.
2 · Set out
Apr 22 to Jun 22
Keyed to the ~Apr 15 last frost. Sow 0.25" deep, 24" apart.
Harvest
~73 days later
~12 lb per plant over ~8 weeks.
Missouri spans more than one climate: Zone 6 is the most common zone, but the state runs 5b to 7a. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
In Missouri: watch for
The pests that find tomatoes here.
A middle-length season, about 188 frost-free days, means tomato, slicing overlaps tomato hornworm for a stretch each summer. Check plants every week or two and treat early.
Big green caterpillars strip leaves and leave black droppings.
Organic fix: Handpick at dusk; spray Bt on the young ones.
Clusters on new growth, sticky leaves, curling tips.
Organic fix: Blast with water, then insecticidal soap or neem.
Dark spots with concentric rings, starting on the lowest, oldest leaves.
Organic fix: Remove affected leaves, mulch to stop soil splash, space for airflow.
Greasy, water-soaked blotches in cool, wet spells. No rings, and not bottom-up.
Organic fix: Pull infected plants fast, keep leaves dry, use neem as a preventive.
Septoria leaf spot
Many small tan spots with dark brown edges, low leaves first, no rings inside.
Organic fix: Strip the lowest leaves, mulch against soil splash, stake for airflow.
Your season math: Missouri gives tomatoes about 188 frost-free days, and it needs roughly 73 days to a first harvest. It's a one-planting crop, so time that single sowing well.
Planting tomatoes in Missouri: questions
When should I plant tomatoes in Missouri?+
In a typical Missouri year, sow tomatoes or set out transplants between Apr 22 to Jun 22, keyed to the state's median last frost around Apr 15. Your exact dates shift with your ZIP code and microclimate.
When do I start tomatoes seeds indoors in Missouri?+
Start seeds inside about 6 weeks before set-out: roughly Mar 11 to May 11 for a typical Missouri season.
What USDA zone is Missouri?+
Missouri spans zones 5b–7a, mostly zone 6. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many tomatoes plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.