Sow winter radish now: the underrated autumn classic
While the summer harvest is in full swing, what ends up on your plate in October is decided now. Winter radish is the easiest way to fill beds that have just opened up.
Garlic out, early potatoes out, the first lettuces harvested — by late July, gaps are opening up in many beds. That’s exactly where winter radish fits in: robust, low-maintenance, and with a harvest window stretching well into late autumn. Sow now and you’ll get a second full crop from the same patch.
Why late July is the perfect moment for winter radish
Radish can be sown in spring and summer — but the July and August sowing is the most rewarding. The soil is warm, germination takes just a few days, and the shortening days from August onwards keep the plants from bolting prematurely. Varieties like the classic black winter radish or mild Asian types build up sturdy roots by October that you can harvest well into November.
There’s a crop rotation bonus too: after garlic, onions or early potatoes, the soil is loosened and free of close relatives — ideal starting conditions.
How to sow it right
Sow directly into the bed, 2 to 3 centimetres deep, in rows about 25 centimetres apart. Within the row, the plants will eventually need around 15 centimetres of space — you can sow more densely and thin the seedlings to that spacing once they’re up. Don’t toss the thinned seedlings: the leaves add a fine peppery note to salads.
One thing matters in summer heat: keep the seed furrow evenly moist until germination. A thin mulch of slightly dried grass clippings between the rows helps lock moisture into the soil.
Location and neighbours: what radish cares about
Radish likes sunny to semi-shaded spots and deeply loosened soil — compaction leads to crooked, forked roots. Fresh manure or heavy nitrogen feeding is off limits, otherwise you’ll get lots of leaves and little root.
In companion planting, radish is easy-going but has clear limits: lettuce and spinach make good neighbours, and it’s happy next to tomatoes too. What doesn’t belong nearby are brassicas — radish is a crucifer itself and shares pests like flea beetles and diseases like clubroot with cabbage. For the same reason, avoid sowing radish in a bed that already held cabbage, radishes or rocket this year.
Care until harvest
The most important factor is even watering. If the soil keeps drying out, the roots turn woody and unpleasantly hot; a heavy downpour on dry soil can even make them split. It’s better to water deeply twice a week than a little every day.
Against flea beetles — small black beetles that chew holes in the leaves — a fine-mesh insect netting right from sowing helps, combined with regular hoeing and moist soil. Harvest starts in October, once the roots have reached their variety’s typical size. Stored in a cool cellar, packed in moist sand, winter radish keeps for several months.
And what comes from August onwards?
Winter radish is just the start of the autumn sowing season. From early August, the windows open for spinach and turnips, and from mid-August lamb’s lettuce follows — all three handle the shortening days with ease and keep delivering when the rest of the garden has long clocked off.
If you want to plan which gap gets which crop: in Rootivo, the bed editor shows you instantly which neighbours and which crop rotation fit that open spot — including a warning if a crucifer already grew there this year.
Im Lexikon: Rettich