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. That’s it for the technical side. Let’s start growing radishes in the backyard now.
Introduction on growing radishes easily.
When you talk about radishes, most people think about the small red balls with green leafs you can buy in the shop. It has a quite pungent and bitter taste. But there are other kinds of radishes. You can also find long white radishes, long white and red radishes, radishes looking like a white carrot, etc…
Around here, radishes are mostly eaten raw. Raw with a pinch of salt, radish can be a delicacy.
Some radishes grow fast, other radishes take a bit of time to grow. As I like fast-growing radishes, I sow the round red saxa. The saxa radish goes from seed to harvest in about 40 to 50 days. Sometimes it takes a little longer and sometimes it goes as fast as 30 days to maturity when growing radishes later in the spring.
What are radishes?
The radish, Raphanus sativus, is, in fact, a cultivated form of horseradish. This vegetable is part of the Brassicaceae family with cousins like kale, broccoli, and cauliflower.
The part we mostly eat, the red or white bulb, is, in fact, the underground part of the stem that thickens up just above the root, so the radish as we know it isn’t a root crop. It’s a bulb made of the stem just above the root part, it’s called the radix.
The strong and peppery flavor can be found in the peel of the small ball. The flesh itself is a bit milder tasting.
The radish has been cultivated for over several thousands of years, but it was only imported in Europe in the 16th century. Now you can find the plant on every continent as a cultivated plant.
Where can I start growing radishes?
A soil amended with rich compost and a good amount of potash is more than enough to grow big, tasty radishes. I personally like to grow radishes in containers in rows because this is easy to check on the plants in case of pests and diseases.
In this region, at about half march, it’s possible to sow directly in the soil. You can even start growing radishes in February in a cold frame if you choose the right variety.
Don’t overuse the fertilizer as this will weaken the plants and develop diseases or attract pests. The plants will also start to bolt a lot sooner.
In my container, I always use a distance of a bit more than one inch between the seeds and between the rows. As radish is an easy to germinate seed, I only use one seed per inch. If you’d like to sow in the soil, you can make rows with a bit more than an inch between the seeds in the row and enough space to cultivate between the rows.
If you use the square-foot method, you don’t need to consider making space to walk between the rows, you can just grow 9 radishes in a square foot.
Radishes can also be used to mark the spots where you planted plants that have a longer growing period, this way it’s easy to see where you have sown your other seeds, and by the time the small plants start to develop, it’s already time to harvest the radishes. There is a small catch with this system which I will be explaining further in the message.
You don’t have to spend a lot of time to take care of radishes. If the plants are in the right soil and they have enough space to grow, you’ll just have to water them in time and that’s it.
It’s best to sow every fourteen days so you can extend your harvest over a couple of months.
The less water the plant gets, the spicier the taste will be.
You can find it weird that I’ll be talking about transplanting radishes as radishes are always sown in their final spot but what I’m going to tell now is only necessary if you want to harvest the radish and the seeds from the plant.
Every year I use some radishes to harvest seeds and I don’t do this the “normal” way. So, I sow my radishes like everyone else does and I wait for the radish to mature as everyone else does but when harvesting, I do something different. Instead of cutting off the greens at the top of the ball, I leave about 1 centimeter of the top part of the radish, on the leafs. I eat the rest of the radish but the small part I left on the greens I just plant it out again.
It takes some time but after a while, the plant will be growing roots and will start bolting. From then on, I just have to wait for the insects to fertilize the flowers and the seeds to grow. When the plant starts dying off, I hang the plants upside down and let them dry thoroughly until the pods are hard and then I start to harvest the seeds. This has worked for me for a couple of years now and I keep on doing it.
If you want to harvest the seeds of your radishes and you let the plant bolt, make sure there’s a stick of about 1 meter (3 feet) to keep the plant straight as it tends to fall over due to weight and the wind.
There is a second point if you want to harvest your radish seeds. Make sure there are no other Brassicaceae plants in the surrounding area as these can cross-pollinate (called xenogamy) and give you totally different plants.
You can harvest radishes by just pulling out the plant of the soil, this tends to be really easy.
With some exceptions, you don’t need any special tools to remove the radish from the soil. Just make sure you, when thinning, not to disturb the neighbor plants too much. This can cause a shock and stop growth for a while, it can even make the next bulb bolt.
Diseases and pests
Although splitting radishes isn’t a disease or pest, I still want to talk about it. Long periods of rain can make the radishes split in half. They will also break when you don’t water them consistently.
The cabbage fly or Delia Radicum
, also called Delia brassicae, can lay its eggs next to the radish plants and the larvae will eat their way through the radishes. This makes radishes useless for consumption. You can use an insect screen if you put it up early enough.
If it’s already too late and the larvae are around, you can use spinosad
on the soil and the plant, this will kill off any sucking, burrowing and plant-eating insects.