What to Plant With Celery: Celery Companion Plants (and Why Not Potatoes)

Celery has a reputation as one of the fussier vegetables to grow at home. It takes a long time from seed, it needs steady moisture all season, and a long cold spell can make it bolt. In return, homegrown stalks have a stronger flavor than store-bought, and you can cut a few at a time for months. This guide covers what extension sources list as celery companions, what to keep away, and how to grow celery so the stalks stay tender instead of turning stringy.

Good companion plants for celery

Onions and garlic

Virginia Extension lists the onion family as celery companions. Onions are narrow and upright, so a row on either side of the celery uses little space. Watch where the onions go, though: the same source lists the onion family as incompatible with beans and peas. More in what to plant with onions and what to plant with garlic.

Cabbage-family crops

Celery is listed as a companion of cabbage, broccoli and their relatives, in both directions of Virginia Extension's table. Both like cool weather and even moisture. Give the brassicas their full spacing so they do not shade the celery once they spread. See what to plant with broccoli. For cabbage itself, see what to plant with cabbage.

Tomatoes, bush beans and nasturtiums

Tomatoes, bush beans and nasturtiums are all listed celery companions. Upright celery can grow along the sunny side of a tomato row, and bush beans fill space at its feet without climbing over it. Nasturtiums can trail along the bed edge. Note that tomatoes and cabbage-family crops are listed as incompatible with each other, so do not put all of these in one small bed. See what to plant with tomatoes and what to plant with beans.

Eggplant

Virginia Extension names eggplant and celery as an example of a companion pairing. Celery goes out earlier in the season and eggplant after nights warm up, so they can share a bed through summer. See what to plant with eggplant.

What not to plant with celery

Virginia Extension lists potatoes and parsnips as incompatible with celery. Potatoes are big, spreading plants that need hilling, which disturbs the soil around celery's shallow roots, so practically they are better in a separate bed. Parsnips are not in our checker, but the same table lists them. Our potato guide lists better potato neighbors, and every pair to separate is in the keep-apart chart.

When to plant celery

Celery is almost always grown from transplants. Cornell's growing guide suggests starting seeds indoors about 10 to 12 weeks before your last frost. The seeds are tiny and need light to germinate, so barely cover them, and keep them warm (about 70°F to 75°F) and moist; they take two to three weeks to come up. After germination, grow the seedlings somewhere cooler, about 60°F to 70°F.

Cornell suggests setting out hardened-off transplants about two weeks before the average last frost, since plants tolerate a light frost. The catch is a long cold spell: about 10 days with nights below 40°F and days below 55°F can trigger bolting. Harden plants off by cutting back water rather than by chilling them, and if a long cold snap is forecast, wait or cover them. Our planting calendar helps you find your frost date to count from.

Planting and spacing

• Spacing: Cornell gives 6 to 12 inches between plants in rows 18 to 36 inches apart; USU uses 12 inches in rows 2 feet apart, and notes that tight planting helps force tall growth and long stalks.
• Soil: rich, well-drained soil with plenty of organic matter that holds moisture.
• Transplants: USU suggests waiting until transplants have three or four mature leaves and a well-established root system.
• Mulch: celery roots are shallow, so mulch to hold moisture and suppress weeds instead of cultivating deeply around the plants.

Watering is everything

Cornell notes that celery is shallow rooted and needs consistent moisture; a lack of water makes the stalks fibrous and bitter. Water deeply and regularly through the whole season, especially in hot, dry spells, and keep mulch around the plants. If you garden in a hot, dry climate, a spot with a little afternoon shade can help celery keep up.

Blanching (optional)

Blanching means keeping light off the stalks for a while so they turn paler and milder. Cornell suggests wrapping the stalks about two weeks before harvest with paper, a cardboard milk carton or similar material. Many modern varieties are sold as self-blanching, and green celery does not need it at all. Blanching changes flavor and color, not how well the plant grows.

A simple bed with celery

1. Celery in a block, 8 to 12 inches apart.

   A block shades the soil and the stalks, and is easier to keep evenly watered.

2. Onions along one side.

   A listed celery companion that takes little space.

3. Bush beans along the other.

   Listed celery companions; keep them away from the onion row.

4. Nasturtiums at the bed edge.

   A listed companion that can trail over the side.

5. Potatoes in a different bed.

   Listed as incompatible with celery.

Our raised bed layouts show how to map a 4×8 bed by the square foot.

Harvest

MSU Extension lists about 80 to 120 days from transplanting to harvest. You do not have to wait for the whole plant: cut a few outer stalks at a time once they are big enough to use, and the center keeps growing. Cut the whole plant at the base when it reaches full size. Stalks left too long in hot weather tend to get tougher and more strongly flavored.

Celery in containers

Celery can grow in a deep container with drainage holes, and a pot makes it easy to give the plant the steady moisture it needs, as long as you check it often. Containers dry out quickly in summer, and dry soil is what turns celery stringy, so water whenever the top of the mix starts to dry.

Frequently asked questions

What grows well with celery?

Extension-listed companions for celery in our checker are beans, cabbage-family crops, eggplant, garlic, nasturtiums, onions and tomatoes. The table on this page explains why each pairing works.

What should you not plant with celery?

Our sources list potatoes as a poor neighbor for celery.