Celery in Zone 6B — Midwest

There's nothing like the crisp snap of homegrown celery, and despite what you might think, you *can* grow it here in the Midwest. Fresh celery is a versatile addition to soups, salads, and snacks, and the satisfaction of harvesting your own is hard to beat. Plus, the taste is so much better than what you find at the grocery store.

Sure, we have our share of Midwest weather challenges, from variable springs to summer heat spells, but with careful timing, you can definitely enjoy a successful celery harvest. Our 183-day growing season gives you plenty of time if you plan right.

Celery needs a long head start, so you'll want to begin sowing your seeds indoors in late January through mid February. This gives them about 10 weeks to get a good start before transplanting. Use seed trays or small pots filled with a good seed-starting mix.

Keep the trays warm (around 70-75°F) and provide plenty of light. A heat mat and grow lights are your best bet. Celery seeds are tiny and need light to germinate, so don’t bury them too deeply. I've found bottom watering works best to keep the soil consistently moist without disturbing the seeds.

Remember our moderate-to-late springs here in the Midwest. That early indoor start is key to getting a jump on the season, especially for slow-growing crops like celery.

Transplant your celery seedlings outdoors in mid April through mid May, after the danger of hard frost has passed. It's a good idea to harden them off for about a week before planting. Gradually expose them to outdoor conditions, starting with just a few hours a day.

Space your celery plants about 8-10 inches apart in rows. Keep an eye on the weather forecast around transplant time. We can still get some chilly nights here in the Midwest in early spring, so be ready to cover your seedlings if a late frost threatens.

Celery is a *very* thirsty plant, and consistent watering is crucial, especially during our moderate-to-hot Midwest summers. The key is to keep the soil consistently moist, but not waterlogged. Aim for about 1-1.5 inches of water per week, depending on rainfall.

Check the soil moisture regularly using the "finger test." Stick your finger about 2 inches deep into the soil. If it feels dry, it's time to water. In the Midwest, watering at the base of the plant is generally better than overhead watering, especially with our moderate-to-humid conditions, to help prevent fungal diseases.

Signs of underwatering include wilting leaves and bitter-tasting stalks. Overwatering can lead to yellowing leaves and root rot. A good layer of mulch, like straw or shredded leaves, will help retain moisture and keep the soil cool, especially during our summer heat spells.

You can expect your first celery harvest from early July through late August, about 85 days after transplanting. Look for outer stalks that are at least 8 inches long. You can harvest individual stalks as needed, allowing the plant to continue producing.

Alternatively, you can cut the entire plant at the base when the stalks are 12 inches or longer. If you want milder stalks, try blanching them by mounding soil around the base of the plant a week or two before harvest.

As our first frost approaches in mid- October, harvest any remaining celery. You can also try covering the plants with a blanket or frost cloth to extend the harvest a little longer, but don't expect them to survive a hard freeze.

Here are three common problems you might encounter growing celery in the Midwest:

Bolting from Temperature Stress

• What it looks like: The plant sends up a flower stalk prematurely, and the stalks become bitter and tough.
• What causes it: Fluctuations in temperature, especially cold snaps in spring or early summer. This can be a problem in our variable Midwest springs.
• How to fix/prevent it: Choose bolt-resistant varieties. Start seeds indoors early to avoid early-season cold snaps. Use row covers to protect plants during unexpected temperature drops.

Hollow Stalks

• What it looks like: The center of the celery stalks is hollow instead of solid.
• What causes it: Inconsistent watering and nutrient deficiencies, particularly a lack of boron.
• How to fix/prevent it: Water regularly and deeply, especially during dry spells. Amend the soil with compost before planting. Consider a soil test to check for nutrient deficiencies.

Stringy Stalks from Heat

• What it looks like: The celery stalks are tough and stringy, making them less palatable.
• What causes it: High temperatures and lack of water during our summer heat spells.
• How to fix/prevent it: Provide consistent moisture, especially during hot weather. Plant in a location with partial shade during the hottest part of the day. Mulch well to keep the soil cool.

Midwest Specific Challenges: Our moderate-to-hot summers, combined with moderate-to-humid humidity and wet-summer rainfall, can create a challenging environment for celery. Consistent watering is key to preventing hollow and stringy stalks. Be prepared to protect plants from both early-season cold snaps and mid-summer heat waves.

Companion planting can help your celery thrive in the Midwest garden.

Good companions include:

• Green beans: They fix nitrogen in the soil, which benefits celery's growth.
• Cabbage: It deters some common celery pests, like cabbage white butterflies.
• Tomatoes: They provide some shade, which can help protect celery from summer heat.
• Onions: They repel some insects that might bother celery.

Avoid planting carrots near celery. Carrots and celery attract the same pests, so planting them together can increase the risk of infestation.