Explainers

How to grow radishes

Low-maintenance with a speedy turnaround, the radish is this season’s hero for “instant” crop gratification.

By Mat Pember

Low-maintenance with a speedy turnaround, the radish is this season's hero for "instant" crop gratification, says Mat Pember.

With the onset of winter we find ourselves reaching for life's little comforts. A slow-cooked meal and glass of red are as welcome as a sleep-in. So, in these cool months reach for a vegetable that suits the chill of winter - the humble radish.

While radishes are hardy enough to grow year round, warm temperatures cause them to bolt to seed prematurely, so it's best to grow them in the cooler months. Furthermore, being fast and easy to grow, they're the ultimate gardening confidence booster. Speaking for a generation that often expects instant gratification, the radish may just be our champion.

To begin with, source seeds from a reputable supplier (ahem, like The Little Veggie Patch Co).

We like the Cherry Belle, a familiar heirloom variety with red skin, white flesh, a sharp peppery taste and the same name as that of our favourite Indonesian girl group. There is, however, a whole world of weird and wonderful radishes out there, so comb the planet for more obscure varieties.

Radish seeds are as hard as rock and benefit from a soak overnight before planting to expedite the germination process. Simply drop the seeds into a jar, fill it with water and leave overnight. Meanwhile, take the opportunity to prepare a location in your patch.

A rule of thumb for root vegetables is to plant them in free-draining soil, not in that gluggy bog where your mint does so well. If you're growing them in a pot, use good organic potting mix. While radishes tolerate partial shade, too little sunlight will shift the plants' focus onto growing foliage to chase the sun rather than developing roots.

Once the soil is ready, sow seeds directly into the patch. Use the tip of your finger to create furrows that are about a centimetre deep and five centimetres apart. Watering is key here, because root vegetables are notoriously thirsty, but also prone to rot. Water every morning so the plants can draw on it throughout the day when they need a drink most. The seeds should germinate within three days and the crop will be ready to harvest in a month or so.

Perhaps the most heartbreaking process when growing radishes is thinning the seedlings. After about two weeks, there will be densely packed growth - what a great gardener you are. While each and every one of these plants will feel like one of your babies, it's necessary to cull a few to give your little radishes some space to grow. Pull them out gently, to avoid disturbing neighbouring plants, so that those remaining are spaced about five centimetres apart.

Radishes grow so fast that they experience little trouble in the way of pests, which are most active at night and generally attracted to moisture. By maintaining a morning watering routine, your patch should be reasonably dry come night-time and far less inviting for nocturnal invaders such as snails and slugs. A good watering routine really is the best pest prevention.

We let our radishes grow until the roots are at least three centimetres in diameter. But ultimately, when to harvest is a matter of personal preference; after about a month pull a few out to taste and assess the size. Unlike many root vegetables, radishes can't be left in ground beyond their prime, as they become tough and pithy. A timely harvest will keep well when properly stored in the fridge.

So, with winter comfort food such as stews and roasts on the menu, use your radish harvest for a crisp, fresh counter-balance and no one need know how easy they are to grow.

Tip of the month: culling seedlings
No one likes to see something go to waste and, for any seed that has managed to grow into a seedling, cutting its life short so early is an unbearable thought. In fact, tell a gardener to pull a perfectly healthy seedling from their patch and they're likely to cry murder. But for the greater good, a cull of your overcrowded seedlings is necessary.

Room to grow is imperative for fledgling plants to thrive. Without space to move, seedlings will start competing with each other - fighting for water, nutrients and sunlight - and once the battle commences there can be no winners. The answer is to cull quickly and cull cleanly. As soon as your seedlings are large enough to handle, cull away.

Less is more doesn't always apply, but this is one of those instances when the rule rings true, because less healthy plants that are adequately spaced in your patch will always produce more than too many plants packed in together. So there is no time to get sentimental - for the greater good, it's a job that must be done.