Knowing when to plant seeds in Ohio is the first step to a successful garden. Your timing depends heavily on your location and the specific plants you want to grow.
Ohio’s climate spans USDA Hardiness Zones 5 and 6, with some microclimates along Lake Erie. This means our springs can be unpredictable, with late frosts threatening eager seedlings. Getting your schedule right makes all the difference.
When to Plant Seeds in Ohio
This schedule is your essential guide. It breaks down planting by season and plant type, using your average last spring frost date as the anchor. Find your date using a local extension office calendar.
Understanding Your Frost Dates
Your last spring frost is the average date when the danger of frost passes. Your first fall frost is when freezing temps typically return. In Ohio, last spring frosts range from late April in the south to mid-May in the north.
- Northern Ohio (Zone 5b/6a): Last frost around May 15.
- Central Ohio (Zone 6a): Last frost around May 5-10.
- Southern Ohio (Zone 6a/6b): Last frost around April 25-30.
Early Spring Planting (4-6 Weeks Before Last Frost)
These cool-season crops can handle a light frost and even taste better in cool weather. You can sow seeds directly in the garden as soon as the soil is workable—not too wet or frozen.
- Peas
- Spinach
- Kale
- Lettuce & Arugula
- Radishes
- Carrots & Beets
- Onion Sets
Spring Planting (On or After Last Frost)
These are your warm-season favorites. They need warm soil and no frost. Planting to early can stunt them. Wait until soil is at least 60°F for best results.
- Beans (bush and pole)
- Corn
- Cucumbers
- Squash (summer & winter)
- Melons
Starting Seeds Indoors: A Step-by-Step Guide
For tomatoes, peppers, and other slow growers, starting indoors gives you a head start. Here’s how to do it.
Step 1: Figure Out Your Start Date
Check your seed packet. It will say something like “start indoors 6-8 weeks before last frost.” Count back from your frost date on a calender.
Step 2: Gather Your Supplies
- Seed starting mix (not garden soil)
- Containers with drainage holes
- Seeds
- Light source (sunny south window or grow lights)
Step 3: Plant and Grow
- Fill containers with damp mix.
- Plant seeds at depth on packet (usually 2x seed width).
- Cover trays to keep humid until seeds sprout.
- Provide 12-16 hours of bright light daily.
- Water gently when surface feels dry.
Step 4: Harden Off Seedlings
This is crucial! About a week before transplanting, gradually expose plants to outdoor conditions. Start with an hour of shade, increasing time and sun exposure each day.
Ohio Fall Planting Schedule
Don’t forget a second harvest! Many spring crops can be planted in late summer for a fall garden. Count back from your first fall frost date.
- 10-12 weeks before first frost: Plant broccoli, cabbage, and Brussels sprouts from seed or transplants.
- 8-10 weeks before: Sow more lettuce, spinach, kale, and Swiss chard.
- 6-8 weeks before: Quick radishes and turnips can go in.
Tips for Ohio Garden Success
A few local insights can boost your results. Ohio weather keeps us on our toes.
Know Your Soil
Ohio soil is often heavy clay. Amend it with compost to improve drainage and nutrients. A simple soil test from your county extension office is a great investment.
Watch the Weather, Not Just the Calendar
A warm early spring can be tempting. But a late cold snap is common. Have frost protection like row covers or cloths ready for early plantings.
Succession Planting for Continous Harvest
Instead of planting all your lettuce at once, sow a small row every two weeks. This staggers your harvest so you don’t have to much at once.
Common Ohio Planting Mistakes to Avoid
Even experienced gardeners make these errors. Here’s what to watch for.
- Planting too early: Impatience is the biggest cause of seedling loss. Warm soil is better than early soil.
- Not hardening off: Moving indoor seedlings straight outside shocks them, causing sunscald or stunted growth.
- Ignoring crop rotation: Don’t plant the same family (like tomatoes and peppers) in the same spot year after year. It spreads disease.
Ohio Seed Planting FAQ
What month do you start seeds in Ohio?
For most summer vegetables, start seeds indoors in March or April. Cool-season crops like peas can be sown outdoors as early as March if the soil is workable.
When should I plant my garden in Ohio?
Your garden planting is staggered. Start cool-season crops in early spring, transplant warm-season crops after the last frost (late May), and plant fall crops in late July through August.
What seeds can I plant now in Ohio?
The answer changes weekly! In early spring, plant peas and spinach. In late spring, plant beans and corn. In late summer, switch back to broccoli and lettuce for fall.
Is it too late to plant seeds in June?
Not at all! June is perfect for planting seeds for fast-growing crops like beans, cucumbers, and summer squash. You can also start seeds for many fall harvest crops in June.
How do I protect early seedlings from a late frost?
Keep old sheets, frost cloth, or even plastic containers on hand. Cover tender plants overnight when a frost is forcasted, but remember to remove covers in the morning.