Radiant Radishes

The radish belongs to the Brassicaceae family. While we are all familiar with the red radish, other cultivars come in shades of pink, rose, scarlet, pure white, yellow and green, right through to purple and almost black. Their shapes range from oval to turnip-shaped, half-long and long. Because they reach maturity so quickly, they are a wonderful introduction to vegetable growing for children. Even if they won’t eat them, children will love planting and harvesting them.

Now is a busy time for gardeners in subtropical areas, but elsewhere June is the month for taking it easy. Take time to evaluate the past season, be aware of looming cold spells, and keep up your interest with one or two small projects – like growing some crunchy radishes

How to grow them

In milder parts of South Africa, radishes can be planted throughout the year. Where frosts occur, plant them until about three weeks before the average first frost date, as frost will actually improve their flavour!

Radishes will tolerate a wide range of soils but they do best in soil previously prepared with good amounts of compost for a main crop. Rake the soil well and break open any large clods. Sow seed thinly in shallow drills and cover with 1cm of soil. Firm the soil and water well with a fine spray. Keep the rows 15cm apart to allow for good root development.

Radishes grow rapidly so it is important to thin the rows out regularly, keep them free of weeds, and water the crop regularly. By planting succession crops every two weeks, you will be rewarded with radishes for an entire season.


• Sow radishes in situ – they don’t transplant well.
• Enrich the soil with compost before planting. Being such a quick crop, they won’t need fertilising but will benefit from fertile soil.
• If growing in containers, use good-quality, fast-draining potting soil. It can be mixed with some home-made compost.
• Keep the soil moist during germination, which should take place within 5-7 days. Sow thickly and use the thinned-out small leaves in salad. They are as tasty as the radish root, but not as peppery.
• Water regularly as radishes need to grow quickly if they are to be plump and crunchy. Uneven or irregular watering can cause radishes to split.

How to harvest them

Keep an eye on your radishes as you will be able to start harvesting from 3-5 weeks after planting. They must be pulled out before they swell too much.

Damaged or diseased roots should be discarded immediately to prevent an infestation of pests or further disease. Pull out the radishes when you see the top of the radish starting to push out of the soil. If they are left too long they become woody and unpleasantly pungent. If you plan to store radishes, remove the tops before refrigerating. This keeps them crisp and fresh.

What if radishes develop leaves without roots?

In winter the cause could be too little sunlight. They need several hours of direct sunlight for the roots to develop. It could also be that plants have not been thinned out, which can also stunt root development. In summer the cause is usually hot weather, which encourages the plant to bolt and try to set seed.

Try this fresh and tasty radish tzatziki recipe!

The Gardener