Celery in Zone 3B — Midwest

Celery might seem like a grocery store staple, but homegrown celery has a brighter, fresher flavor you just can't beat. Plus, it's incredibly versatile in the kitchen, from soups and stews to salads and snacks. The satisfaction of harvesting crisp, juicy celery stalks after nursing them through our Midwest growing season is truly rewarding.

Our Midwest weather, with its variable springs and occasional summer heat spells, can be a bit tricky for celery. But don't worry! With a little planning and attention to timing, you can definitely grow beautiful celery in our 118-day growing season. We just need to get those seeds started early!

You'll want to start your celery seeds indoors in early to late March, roughly 10 weeks before you plan to transplant them outside. Celery seeds are tiny and need light to germinate, so don't bury them too deeply. Just sprinkle them on top of your seed starting mix and gently press them in.

Use seed trays with a good quality seed starting mix, and keep them consistently moist. Bottom watering works great for celery seedlings to prevent damping off. Place your trays in a warm spot (around 70-75°F) under grow lights. Remember, our Midwest spring is moderate-to-late, so you'll want to keep those seedlings happy indoors until the weather stabilizes.

Celery can be slow and a bit challenging to start, so don't be discouraged if germination takes a while. Starting them indoors early gives them a head start before our Midwest summer hits.

Transplant your celery seedlings outdoors from mid-May through early June, after the danger of frost has passed. Before transplanting, harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the sun, wind, and temperature changes.

When you're ready to plant, space your celery plants about 8-10 inches apart in rows. Our Midwest weather can still be unpredictable around transplant time, so keep an eye on the forecast and be prepared to cover your young plants if a late frost threatens.

Celery is a very thirsty plant, and consistent watering is absolutely critical for success in the Midwest. With our moderate-to-hot summers and moderate-to-humid conditions, celery needs consistently moist soil to thrive. Even a short dry spell can cause hollow, bitter stalks.

During the warmer months, aim to water your celery deeply at least 1-2 times per week, providing about 1-2 inches of water each time. Stick your finger about 2 inches into the soil – if it feels dry, it's time to water. Watering at the base of the plants is best, but overhead watering is fine too, especially since our humidity isn't as intense as some other regions.

Keep a close eye on your plants. If the leaves start to wilt or turn yellow, they're likely underwatered. On the other hand, soggy soil and yellowing lower leaves can indicate overwatering. A good layer of mulch, like straw or shredded leaves, can help retain moisture and regulate soil temperature, which is especially helpful during those summer heat spells.

You can expect to start harvesting your celery from mid-August through late September, about 85 days after transplanting. The outer stalks are usually the first to mature.

You can harvest individual stalks when they are at least 8 inches long by cutting them off at the base of the plant. Or, you can wait and harvest the entire plant when the stalks are 12 inches or longer by cutting the whole plant off just below the soil surface. If you want milder stalks, you can blanch them by mounding soil around the base of the plants a week or two before harvest.

Keep harvesting regularly to encourage continued production. As our first frost approaches in mid-September, you can extend your harvest by covering your celery plants with a blanket or row cover on cold nights.

Here are some common issues you might encounter growing celery in the Midwest:

Bolting from temperature stress

• What it looks like: The plant starts to produce a flower stalk prematurely, and the stalks become bitter and tough.
• What causes it: Temperature fluctuations, especially cool spells after warm weather, can trigger bolting. This is more common in our variable Midwest spring.
• How to fix/prevent it: Choose bolt-resistant varieties. Start seeds indoors early to avoid temperature stress. Provide consistent watering and mulch to regulate soil temperature.

Hollow stalks

• What it looks like: The inside of the celery stalks are hollow, and the stalks may be tough and bitter.
• What causes it: Inconsistent watering and nutrient deficiencies, especially boron deficiency. Celery is very thirsty.
• How to fix/prevent it: Water deeply and regularly, especially during dry spells. Amend your soil with compost or a balanced fertilizer before planting. Consider a foliar spray of boron if you suspect a deficiency.

Stringy stalks from heat

• What it looks like: The celery stalks are tough and fibrous, making them unpleasant to eat.
• What causes it: Prolonged exposure to high temperatures. Common during our Midwest summer heat spells.
• How to fix/prevent it: Provide afternoon shade for your celery plants during the hottest part of the day. Water deeply and regularly to keep the soil cool. Choose heat-tolerant varieties.

Midwest Specific Challenges: Our moderate-to-hot summers, combined with moderate-to-humid conditions and wet-summer rainfall, mean that consistent watering and good air circulation are essential for growing healthy celery. Be prepared to adjust your watering schedule based on the weather and keep an eye out for signs of stress.

Companion planting can be a great way to improve your celery crop in the Midwest. Green beans are good companions because they fix nitrogen in the soil, which celery needs. Cabbage also benefits celery because it deters cabbage white butterflies, which can sometimes bother celery.

Tomatoes are good companions because they provide shade, which can help protect celery from our summer heat spells. Onions deter some pests that might bother celery. Avoid planting carrots near celery, as they compete for the same nutrients in the soil.