How to Grow Radishes

Overview

Radishes are one of the fastest crops in the garden, ready to eat in as little as 3-4 weeks from sowing. They are perfect for filling gaps between slower-growing vegetables and ideal for introducing children to growing food. Both summer and winter varieties can extend your harvesting season.

Health Benefits

Good source of Vitamin C: Even a small handful of radishes contributes to your daily Vitamin C intake, supporting immune function and skin health.

Natural digestive aid: Radishes have traditionally been used to support digestion and may help stimulate bile production for better nutrient absorption.

Contains glucosinolates: These sulphur-containing compounds, which give radishes their peppery bite, are being studied for their potential antioxidant and protective properties.

Soil Preparation

Radishes prefer light, well-drained soil that has been raked to a fine tilth. They are not fussy about soil type but grow best in soil that has not been freshly manured. A neutral to slightly acidic pH of 6.0 to 7.0 is ideal. Containers and window boxes work well for small-rooted summer varieties.

Sowing & Planting

Sow summer radish seeds directly outdoors from March to September in shallow drills 1cm deep, spacing rows 15cm apart. Thin to 2.5-3cm apart when seedlings appear. Make small sowings every 2-3 weeks for a continuous supply rather than one large batch. Winter radishes are sown in July and August and need wider spacing.

Care & Maintenance

Water regularly and evenly to ensure fast, steady growth. Radishes that grow too slowly become woody and unpleasant. They need very little feeding if the soil is reasonably fertile. Keep weeds down and protect from flea beetle by covering with fleece in spring.

Harvesting

Pull summer radishes as soon as they reach usable size, usually 3-4 weeks after sowing. Do not leave them in the ground too long or they will become pithy and hot. Winter radishes take longer and are harvested from October, storing well in damp sand for several months.

Common Problems

Flea beetle makes small round holes in leaves, especially in hot, dry weather. Cover with fine fleece and keep soil moist.

Bolting occurs when radishes are sown too late in summer or experience drought stress. Keep watering consistent and choose bolt-resistant varieties.

Splitting happens with irregular watering. Maintain even soil moisture throughout the growing period.

Companion Planting

Radishes are excellent companions for lettuce, peas, and carrots. They have no significant plants to avoid and make a useful catch crop between rows of slower-growing vegetables.