Utah Tall Celery
Sowing:
Celery grows best as a fall crop in most climates, so start your seeds about 10 weeks before the last spring frost. Soak them overnight to speed germination, then sow them in a flat in rows 1″ apart; keep the soil moist and keep the flat out of direct sun. Germination often takes two or three weeks. When the plants reach about 2″ tall, transplant them into pots; set them out in the garden when they reach 6″ tall or after the last frost date. Space them 6-8″ apart in rows 2-3′ apart, putting them at the same soil level as in the pots. Make sure the soil is enriched with compost or other organic matter. For companion planting benefits, plant celery with tomatoes, cauliflower, or cabbage.
Growing:
Provide water each week; feed them with compost or fertilizer every two weeks. Carefully remove weeds. If the temperature falls below 55 degrees F consistently, cover the plants. Growing success for celery depends on plentiful moisture, enriched soil, and protection from high temperatures and sun. For a sweeter, more tender taste, many gardeners blanch their celery about two weeks before harvesting it; this is accomplished by wrapping newspaper around the stalks up to the point where the leaves begin. Other methods use boards to shield the stalks from the sun, or simply mound dirt up to cover the stalks.
Harvest:
Cut off the entire plant at soil level as soon as it reaches a diameter of 3″, or remove individual outer stalks when they reach 12″ tall. Celery leaves can also be used, such as for flavoring like an herb or in salads.
Seed Saving:
To save seed in areas where the ground freezes over winter, it will be necessary to dig up the celery before the first heavy frost; cover the roots with dirt and the stalks with straw, and keep them in a humid location with near freezing temperatures. In the spring, remove rotted or damaged stalks and set out the plants after the last frost. In warmer climates, leave the celery in the ground and cover them thickly with mulch over winter. In the spring, allow the plant to flower; when the seed heads on the flower grow brown and dry, cut them off and allow them to fully dry indoors. Remove as much chaff as possible, then store in a cool, dry place.
Common Pests:
Aphids: The common name for many species of aphids that infect gardens is plant lice, as that is exactly what they look like. Aphids sucks plant juices, weakening the leaves and the stems. Fortunately there are a dozen major predators to every type of aphid. The most common predator are the lady beetle, small wasps, syrphid fly larvae, and lacewings. Most of the time insecticide is not needed for removing aphids, a strong stream of water from the hose will do just fine, as will soapy water.
Cutworms: They are among the most inefficient eaters in the insect world. A few bites and they are done, which means a single cutworm can kill a dozen plants in a few days time. Fortunately this damage is easily preventable, when you transplant the seedlings, encircle them with a protective collar made from a paper cup with the bottom punched out. Another method is to stick a toothpick or twig down the side of the plant stem. When the cutworm attempts to encircle the stem to girdle it, the tough wood gets in the way.