Overview
- Name: Celery
- Botanical Name: Apium graveolens
- Plant Family: Apiaceae (Carrot Family)
- Native to: Europe and the Mediterranean region, Southwestern Asia
Description
Celery is a biennial vegetable commonly grown as an annual, featuring fleshy, upright, fibrous stalks reaching a height of 40-60 cm (16-24 in). The plant has pinnate, finely divided leaves. In its second year the plant produces clusters of small, creamy-white flowers arranged in dense umbels (short flower stalks emerging from a common point resembling an umbrella in shape), which then form small, brown, broad oval seeds, each measuring 1.5–2 mm (less than 0.1 inches) in both length and width.
Interesting Facts
- Historically, celery was first cultivated for medicinal purposes before 850 B.C., well before it became a common food item. The ancient Egyptians and Romans utilised celery and its seeds to alleviate conditions like arthritis and to soothe the nerves.
- Celery seeds contain apigenin, a compound believed to have anti-inflammatory properties.
- Celery seed extract also includes an important compound called 3-n-butylphthalide, or 3nB, which also imparts the distinctive flavour and smell of celery, which can reduce blood pressure and alleviate arthritis symptoms.
- It is a good source of vitamin K, which is essential for blood clotting and bone health. Celery also contains potassium, and folate. The antioxidants in celery include flavonoids, vitamin C, as well as lunularin and bergapten to neutralise harmful free radical compounds.
- Celery is part of the same family as parsley, fennel, and carrots.
- Celery is 95% water and rich in fibre, making it a low-calorie snack that helps in hydration.
Basic Growing Information
- Sun Requirements: Full sun to partial shade
- Water Requirements: High
- Soil Types and Properties: Fertile, well-draining loamy soil with high organic matter content
- Soil pH: 6.0 to 7.0
- Pot Size for Container Growing: At least 30 cm (12 in) deep
Planting
Celery is a cool-season crop, which prefers cool climates, with optimal growing temperatures between 15-21°C (59-70°F). It thrives in cool, moist locations, and requires constant moisture. This vegetable can tolerate some shade, but does not tolerate heat. It can withstand temperatures ranging from 5-27°C (41-80.6°F), but if temperatures fall below 12.7°C (55°F), it is advisable to use protective coverings to shield the plants and prevent bolting (prematurely going to seed).
- Best Time to Plant:
- Climates with freezing winters: Start seeds indoors 10-12 weeks before the last frost; transplant outdoors in early spring.
- Climates with milder winters: Sow seeds outdoors in late summer or early autumn.
Note: Check gardening calendars for the best planting times in your location
- Spacing: 20-25 cm (8-10 in) between plants, 30 cm (12 in) between rows
- Seed Sowing Method: Sow seeds into seed tray and then transplant seedlings
- Seed Sowing Depth: 0.5 cm (¼ inch) deep
- Time to Harvest: 17-18 weeks when planted from seed
- Mature Height/Spread: 40-60 cm (16-24 inches)
- Grown From: Seeds
For optimal results, celery seeds should be started indoors or in a glasshouse and then transplanted outdoors. Germination is slow, and soaking the seeds in warm water overnight can enhance germination success.
Sow seeds in seedling trays or punnets filled with quality potting or seed-starting mix, keep them well watered and do not allow them to dry out. Maintain soil temperatures between 12.7-21°C (55-70°F), aiming for the ideal temperature range of 15-21°C (60-70°F) for optimal germination.
Seedlings should emerge within 2-3 weeks and can be transplanted into individual pots when they reach 5 cm (2 in) in height. Once the seedlings are 15 cm (6 in) tall and have been hardened off, they are ready for transplanting into the garden.
Care and Maintenance
- Watering Tips: Plants need continuous moisture, so it’s important to maintain consistently moist soil to avoid stringy stalks. Applying mulch around plants helps retain soil moisture and prevent weed growth.
- Fertilisation: Celery is a heavy feeder and should be fed every 3-4 weeks with a balanced fertiliser during growth.
- Pruning: Not typically necessary.
- Support: Not required.
Should temperatures be predicted to fall below 12.7°C (55°F), it is advisable to protect the plants with cloches to prevent the development of weak stalks. Extended exposure to temperatures lower than this can lead to the plant bolting (going to seed).
Plants may remain in the garden until autumn (fall) and can withstand a light frost, but not ongoing severe frosts. Uncovered stalks will darken and become more fibrous compared to tender young stalks.
Growing Difficulty
- Moderate Difficulty
Growing Tips
- Blanching (shielding the stalks from light) is sometimes practiced to produce tender, pale stalks and to reduce bitterness, by wrapping them with paper or soil two weeks before harvest.
Understanding Blanching – How to Blanch Celery Stalks
Blanching celery is a gardening technique used to make the stalks tender and milder in flavour. It involves blocking light from reaching the stalks to reduce their bitterness and improve their color, usually resulting in pale, crispy, and less fibrous celery.
Self-blanching varieties of celery are also available.
Here’s how blanching is done:
- Timing: Begin blanching celery a couple of weeks before harvest. For most varieties, this is 10-14 days before harvesting.
- Covering the Stalks:
- Mounding Soil: One traditional method is to mound soil around the base of the celery stalks. This creates a covering that blocks sunlight.
- Use Tubes or Wraps: You can also use cylindrical tubes, like cardboard or plastic sleeves, or wraps such as newspaper, to encase the celery stalks. Make sure the covering extends up the entire length of the stalks, leaving only the tops exposed.
- Commercial Blanching Collars: Some gardeners use special blanching collars, which are reusable and specifically designed for this purpose.
- Securing the Covering Material: Ensure the covering material is firmly placed so it stays secure but not so tight that it damages the stalks.
- Harvesting: Harvest the celery stalks once they’ve been blanched for 10-14 days, while they’re still pale and tender.
Blanching helps make celery more appealing and improves its taste by reducing the bitterness commonly associated with its outer, sun-exposed stalks.
Companion Plants
- Good companion plants include: Leeks, onions, and tomatoes.
- Avoid planting near: Parsley.
Common Pests and Diseases
- Pests: Slugs, celery leaf miner
- Prevention: Use diatomaceous earth, encourage natural predators.
- Diseases: Pink rot, celery mosaic virus
- Prevention: Ensure good air circulation, rotate crops.
Harvesting
- Harvest Time: Celery can begin to be harvested when the stalks are around 2.5cm (1 in) thick, about 20 cm (8 in) tall, and leaves are vibrant.
- Harvesting Tips: Cut stalks from the base, taking care not to damage the crown if further growth is desired. Unblanched celery may be harvested as required by slicing the stalks from the outer edges inward. Blanched celery should be harvested by cutting the whole plant just beneath the soil surface.
Propagation
- Produce new plants from seeds.
Culinary Uses
- Celery stalks are commonly used in salads, soups, stews, and stir-fries, or as a crunchy snack with dips.. Leaves add flavor to salads, and seeds are ground for seasoning.
In conclusion, celery is a rewarding vegetable for the patient gardener, providing crunchy stalks and flavorful leaves. With care, consistent watering, and attentive pest management, you’ll find this versatile crop a valuable addition to your garden.
Please feel free to add any growing tips in the comments below, and also include your climate/hardiness zone if it’s helpful.