When To Plant Kale In Ohio

If you’re planning your Ohio garden, knowing when to plant kale in Ohio is the first step to a great harvest. This cool-season champion thrives in our state’s spring and fall weather, and timing it right makes all the difference.

Plant too early in spring, and a hard freeze might set you back. Plant too late in fall, and your plants won’t mature before winter. This guide gives you the simple schedule and tips you need for success.

Kale is a hardy plant that prefers cool temperatures. It can handle a light frost, which actually makes the leaves taste sweeter. The key is to avoid letting it mature in the peak summer heat, as this can make the leaves bitter and tough.

For most Ohio gardeners, there are two perfect planting windows: early spring and late summer.

Spring Planting Schedule

Your goal for spring is to get kale seeds or transplants into the ground so they can grow and be harvested before the summer heat arrives.

Direct Seed Outdoors: Sow seeds directly into your garden soil 2-4 weeks before your last expected spring frost. In northern Ohio, this is typically late April. In southern Ohio, you can start in early to mid-April.
Start Seeds Indoors: For a head start, begin seeds indoors 5-7 weeks before your last frost date. This means starting them in late February to early March. Transplant the sturdy seedlings outdoors 2-3 weeks before the last frost.

Fall Planting Schedule

Fall is often the best time for kale in Ohio. The cooling temperatures create ideal growing conditions, and frost improves the flavor. Plants established in fall can often survive winter under snow or with protection for early spring harvesting.

Direct Seed for Fall: Count back 6-8 weeks before your first expected fall frost. For most of Ohio, this means planting seeds in early to mid-August. Your first frost usualy occurs in October.
Transplant for Fall: Start seeds indoors in mid-July and transplant them into the garden in late August. This gives them a strong root system to tackle the coming cooler weather.

Ohio Frost Date Zones

Since Ohio’s climate varies, here’s a general guide based on region. Always check a local almanac for the most accurate dates for your specific town.

Northern Ohio (Cleveland, Toledo): Last spring frost around May 15. First fall frost around October 15.
Central Ohio (Columbus, Dayton): Last spring frost around May 5. First fall frost around October 20.
Southern Ohio (Cincinnati, Athens): Last spring frost around April 25. First fall frost around October 25.

How to Plant Kale Successfully

Once you have your dates, follow these steps for healthy plants.

1. Choosing a Location & Soil Prep

Kale needs at least 6 hours of sun, but it appreciates some afternoon shade in summer. The soil should be fertile and well-draining.

Work in 2-3 inches of compost or aged manure into the top 6 inches of soil.
Aim for a soil pH between 6.0 and 7.0. A simple soil test can confirm this.

2. Planting Seeds or Transplants

Whether using seeds or young plants, the method is straightforward.

For seeds: Plant them ¼ to ½ inch deep. Space seeds about 1 inch apart.
Once seedlings are a few inches tall, thin them to stand 12-18 inches apart. You can eat the thinned seedlings as microgreens!
For transplants: Dig a hole the size of the root ball. Place the plant in, keeping it at the same depth it was in its pot. Space plants 12-18 inches apart in rows 18-24 inches apart.
Water thoroughly after planting to settle the soil.

3. Ongoing Care Tips

Kale is low-maintenance, but a little attention yields better leaves.

Watering: Keep the soil consistently moist, providing about 1-1.5 inches of water per week. Use a mulch layer to help retain moisture and suppress weeds.
Fertilizing: Feed plants with a balanced organic fertilizer or a side-dressing of compost about a month after transplanting.
Pest Control: Watch for cabbage worms and aphids. Handpick worms or use an organic spray like Bt (Bacillus thuringiensis). Row covers installed right after planting can prevent most pest problems entirely.

Harvesting and Winter Care

You can start harvesting young leaves when they are about the size of your hand. Always harvest from the bottom of the plant, leaving the central growing tip intact to produce more leaves.

For fall-planted kale, it will often survive winter with simple protection. After the first hard frost, mound straw or leaves around the base of the plants. Under a layer of snow or with a cold frame, kale can stay alive and harvestable on mild winter days and will regrow vigorously in early spring, giving you a very early crop.

Recommended Kale Varieties for Ohio

Some varieties perform exceptionally well in our climate. Consider these reliable choices:

Winterbor: A curly kale that is extremely cold-tolerant, perfect for fall planting and winter harvests.
Lacinato (Dinosaur Kale): Has long, strappy blue-green leaves. It’s heat-tolerant for spring planting and sweetens nicely after frost.
Red Russian: A flat-leaf kale with reddish stems. It’s tender, sweet, and matures quickly, great for both spring and fall plantings.
Vates Blue Curled: A dwarf, cold-hardy curly kale that is a dependable all-around performer.

Common Problems and Solutions

Even with good timing, you might face a few issues. Here’s how to handle them.

Bolting: If your kale sends up a tall flower stalk, it’s bolting, usually triggered by warm temperatures. The leaves become bitter. Focus on fall planting or choose bolt-resistant varieties for spring. Harvest promptly to delay bolting.
Yellowing Leaves: This can be a sign of overwatering, poor drainage, or a nitrogen deficiency. Ensure good soil drainage and consider a nitrogen-rich feed like fish emulsion.
Holes in Leaves: Almost certainly cabbage worms. Inspect the undersides of leaves and remove pests by hand. Row covers are the best prevention.

FAQ: Your Kale Questions Answered

Can you plant kale in the summer in Ohio?

It’s not ideal. Summer heat stresses kale, making it bitter and more prone to pests. For a summer harvest, you need to plant in very early spring so it matures before peak heat, or provide significant afternoon shade.

How late can you plant kale in Ohio?

For a fall crop, you can succession plant seeds until about 8 weeks before the first hard frost. In central Ohio, that’s a last planting around mid-August. Transplants can go in a few weeks later, up to early September, for a later harvest of smaller leaves.

Does kale come back every year?

Kale is technically a biennial, meaning it lives for two years. In Ohio, we usually grow it as an annual. However, fall-planted kale that survives winter will try to flower and set seed in its second spring. You can harvest the early spring leaves but then should replant for the best quality.

What can I plant next to kale?

Good companions include herbs like dill and mint, which deter pests, as well as onions, beets, and lettuce. Avoid planting it next to other brassicas like broccoli or cabbage, as they share the same pests and diseases.

By following these planting times and care tips, you’ll be able to enjoy homegrown kale from your Ohio garden for much of the year. The crisp, fresh leaves from your own backyard are worth the little bit of planning it takes.