Introduction
Radishes are a fast-growing, easy-to-grow root vegetable that can be harvested in as little as four weeks. Their crisp texture and peppery flavour make them a popular addition to salads and sandwiches. Radishes are ideal for both novice and experienced gardeners in the southeast of the UK.
Why grow radish?
Radishes are packed with vitamins C and B6, folate, and potassium. Growing your own radishes ensures a fresh, pesticide-free supply. Additionally, their quick growth cycle allows for multiple harvests throughout the growing season, providing a constant supply of this nutritious vegetable.
Suitability for different growing environments
Radishes thrive in well-drained, fertile soil and prefer full sun but can tolerate partial shade. They are well-suited to garden beds and containers, making them a versatile option for various garden setups.
Lifecycle
Radishes are annual plants grown from seeds, that have a lifecycle of around 4-6 weeks from sowing to harvesting, depending on the variety and growing conditions.
Sowing and harvesting periods
Sowing: Early spring to late summer (March to August)
Harvesting: Spring to autumn (April to October)
Recommended varieties
Popular radish varieties for the UK include:
‘Cherry Belle’
‘French Breakfast’
‘Scarlet Globe’
How to sow
Directly sow radish seeds into prepared soil from early spring to late summer. Plant seeds ½ inch (1.25 cm) deep and 1 inch (2.5 cm) apart in rows spaced 6 inches (15 cm) apart. Water well after sowing to ensure good seed-to-soil contact.
You can also sow radish seeds in modules, sowing 4 or 5 seeds per module, aiming for 3 or 4 seeds to germinate. Sow seeds 1cm deep and lightly top water. Once plant leaves start to cover the compost, water more and once the seedlings are growing strongly, switch to bottom watering.
How to prick out/pot on
As radishes are typically sown directly into their final growing position, they do not require pricking out. Thin seedlings to 2-3 inches (5-7.5 cm) apart once they are large enough to handle to allow room for growth.
Where to plant
Choose a sunny or partially shaded location with well-drained soil. Incorporate compost or well-rotted manure into the soil before planting to improve fertility. Rotate crops annually to prevent pests and diseases.
How many to plant (spacing)
Plant radishes 2-3 inches (5-7.5 cm) apart within rows spaced 6 inches (15 cm) apart. Adequate spacing ensures roots have room to develop and facilitates airflow to minimise disease.
How to plant
Directly sow radish seeds into prepared, weed-free soil. Cover lightly with soil, water gently, and mulch to retain moisture and suppress weeds. Water regularly to keep the soil evenly moist during the growing season.
Protecting your plants
Radishes are relatively hardy but can be susceptible to pests like flea beetles and slugs. Use row covers to protect young seedlings and monitor for pest damage. Organic pest control methods, such as handpicking and using slug traps, can help manage infestations.
How to feed and water
Water radishes consistently to prevent the roots from becoming tough or splitting. Apply a balanced fertiliser or compost before planting to provide essential nutrients. Avoid over-fertilising, as it can lead to excessive leafy growth at the expense of root development.
How to propagate, prune/manage while growing
Thin seedlings to ensure proper spacing and promote robust root growth. Remove weeds regularly to reduce competition for nutrients and water. Prune yellowing or damaged leaves to maintain plant health.
How and when to harvest
Harvest radishes when roots reach the desired size, typically 1-2 inches (2.5-5 cm) in diameter. Gently loosen the soil around the roots and lift them carefully to avoid damaging adjacent plants. Cut off the leaves, leaving a small stem to prevent bleeding.
How to store
Store harvested radishes in the refrigerator for up to two weeks. Remove the leaves before storing to extend their shelf life. Radishes can also be pickled for longer storage and culinary variety.
How to eat/cook
Radishes can be enjoyed raw, sliced into salads, or as a crunchy snack. They can also be roasted, sautéed, or pickled for a tangy addition to meals. The leaves are edible and can be used in salads or cooked like other leafy greens.
How to deal with pests and disease
Monitor radish plants for signs of pests like flea beetles, slugs, and root maggots. Use organic pest control methods such as row covers, handpicking pests, and applying diatomaceous earth. Rotate crops and practice good garden hygiene to prevent disease.
When and how to remove the plants
Remove radish plants after harvesting all roots. Cut back foliage and add it to the compost. Rotate crops annually to maintain soil health and reduce pest and disease pressure.
What to plant before and after
Plant radishes after nitrogen-fixing legumes like peas or beans to improve soil fertility naturally. Avoid planting after other root crops to minimise disease and pest issues.
Follow radishes with leafy greens, brassicas, or legumes that benefit from nutrient-rich soil. Rotate crops annually to maximise soil health and productivity.
What to interplant with
Companion plant radishes with carrots, lettuce, or onions to deter pests and maximise garden space. These plants complement each other and promote overall garden health.