Radishes are a must when growing vegetables at home. They can be grown in the garden bed and on the balcony. If you know how to cultivate and harvest properly, you will be rewarded with a bountiful harvest. This article explains what is important when growing radishes and gives valuable tips.
radish
The Raphanus sativus var. sativus, as radishes are scientifically called, are among the easiest to grow and fast-growing vegetables. Even novice growers will find it easy to grow and care for if they do it right and keep important things in mind. This article will provide you with everything you need to know about growing radishes.
location
So that the radish can grow magnificently and impress with a juicy aroma, the right choice of location for cultivation is an important aspect. If you stick to the following points and then determine the location for your sowing, you have already done a major part.
- Minimum outdoor temperatures of five degrees Celsius
- Light conditions: sunny to semi-shady
- half-shady location optimal in summer (does not tolerate hot sun)
- three to four hours of sun a day promote growth
- place protected from drafts
Before, after and mixed culture
Radishes are perfect as a pre- and post-culture for numerous other types of vegetables. As a mixed culture, the Raphanus sativus var. sativus is well tolerated with many different types of plants. Here is a brief overview of your options.
preculture:
- bush beans
- cabbage
- paprika
- Beetroot
- garlic
- tomatoes
post-culture:
- Lamb's lettuce
- Green salad
mixed culture:
- carrots
- peas
- strawberries
- lettuce
- spinach
- cucumbers
- zucchini
- Parsely
- basil
floor
The right soil conditions is another factor on which optimal growth depends. Here you can choose between conventional bedding soil for outdoor planting and substrate for planting in containers or vegetable boxes. The soil/substrate should meet the following points of criticism.
- high, even humidity
- rich in humus
- permeable
- relaxed
- slightly acidic with a pH between 5.5 and 7.0
A substrate should have the same properties. A nutrient-rich substrate enriched with perlite ensures looseness and water permeability. Additional coconut fibers optimize water retention. This is especially necessary when using substrate, otherwise the flavor intensity will suffer if it dries out.
sowing and harvesting time
outdoor
As a rule, most radish varieties can be sown in early spring from March, such as the Saxa, Neckarperl and Cyros varieties. However, you should still protect them with fleece or plastic film from any icy winds and sub-zero temperatures that may arise.
Varieties that are more sensitive to cold, such as Parat, Raxe or Sora, should only be planted outdoors from May after the ice saints. When sowing in March, the foil/fleece can be removed after the ice saints. Sowing is possible until early autumn. The harvest time is around four to six weeks, which is why in autumn the latest sowing date should not be later than mid-September, as experience has shown that temperatures drop below the five degrees Celsius mark from mid/end of October and it would then be too cold for the radishes.
If you have a high need for radishes, it is advisable to sow them every four weeks.
Glasshouse
This radish species can already be cultivated in the greenhouse in February. You can expect the first harvests at the end of March/beginning of April.
sowing
planting distance and planting depth
In order for the radishes to spread undisturbed in their growth and the roots to establish themselves, you should definitely keep an optimal planting distance. This should be between eight and ten centimeters all around. If you do not keep the planting distance and sow too close together, you have no choice but to “separate” the plants that have already grown to about three to five centimetres. This means that you have to remove neighboring plantings, otherwise the growth of the plants will be immensely hampered. The radish tubers remain significantly smaller as a result or there is no development at all.
If you plant Raphanus sativus var. sativus in a row, a distance of between 10 and 15 centimeters between them is sufficient. The seed should be placed about an inch into the ground.
soil preparation
Before sowing the seed, it is advisable to prepare the soil well. Loosen this well with a fine-toothed rake to a depth of between eight and ten centimetres. This ensures that compaction is released and the soil becomes more permeable to water.
In addition, practical tests show again and again that the growth of cruciferous plants is promoted if you enrich the bedding soil with compost. This creates a basis for the optimal supply of nutrients to the vegetable plant. If you plant in substrate, there is no need for additional compost. Also, moisten the soil well before sowing and drain any excess water. Once the seed has been sown, watering is no longer necessary and overwatering is avoided.
TIP: Do not use farmyard manure instead of compost. This promotes pest infestation, which must be avoided at all costs.
sowing
- When sowing in rows, make a long hollow with a garden shovel
- When sowing individually, make a well about one centimeter deep in the soil
- bring the seed into the ground according to the minimum distance
- Row wells about an inch high the seed with soil
- When sowing individually, cover seeds with soil up to the surface
- Press or tap the soil/substrate lightly
- do not water if the soil has been previously moistened
- at temperatures below 5 degrees Celsius, stretch fleece or film over the outdoor seed
- Remove foil/fleece after the ice saints
pour
Water your seeds continuously throughout the growing season until harvest. It is important that the soil does not dry out. In spring and from late summer, the water requirement is usually covered by sufficient rainy weather. In summer, on the other hand, you should check daily whether watering is necessary.
You can check this by doing the thumb test. If the soil surface can be pressed down less than one centimeter, your radishes need water. If you can easily press your thumb deeper than a centimeter into the soil, there is still sufficient moisture. If you let your radishes dry out, this will change the taste and possibly the consistency. Water too much and you risk rotting.
TIP: If you forget to water and the tubers shrivel, soak them in cold water for a few minutes. They pull up the water and the tuber layers tighten again.
Fertilize
If you have already enriched the soil with nutrient-rich compost before sowing, there is no need for further fertilization within the next four to six weeks until the harvest is ready. If you have not prepared the soil, you can also work in compost on the surface afterwards. Since radishes are flat-rooted, a superficial distribution is sufficient. Just make sure it's old, rotted compost, as fresher can contain too many salts that could harm the vegetable plant.
Alternatively, you can give a liquid fertilizer for vegetables, such as Plantation Feed liquid fertilizer from Green24. This promises strong rooting and is made purely from ecological ingredients. This means that adding fertilizer does not affect the safe edibility. This should be added to the irrigation water shortly after the first leaves have formed.
TIP: Do not fertilize with mineral fertilizers that contain nitrogen. These promote leaf growth, but otherwise have no beneficial effect.
To cut
Radishes are not usually cut. Mostly due to care mistakes and/or unsuitable location, brown leaves can form. You should cut these off, as they will continue to draw nutrients even after they have dried up. As a result, these nutrients are missing in the healthy parts of the plant.
Brown leaves and dead plant parts can also be the result of a disease or pest infestation. In this case, you can shorten the radishes to just above the tubers. However, at least two sheets must remain. If the tubers are affected, you usually only have to dispose of the affected plants, because they are usually no longer suitable for consumption.
hibernate
radishes in winter
If you don't want to do without radishes in winter either, you can sow and harvest them in a greenhouse between October and January/February. However, not all varieties are suitable for this, only special ones, such as “Fakir” and “Jolly”. When sowing, proceed as already described under the heading of the same name. The ambient temperature in the greenhouse should never fall below five degrees Celsius. An ambient temperature between ten and 15 degrees Celsius is ideal. Don't forget to water regularly.
harvest
If all the conditions that the Raphanus sativus var. sativus places on sowing, location and care are met, you can expect the first yields when sowing outdoors at the beginning of April if you sowed early in March. A last harvest of the current year is possible at the end of September/beginning of October. Anyone who owns a greenhouse and chooses suitable radish varieties can harvest all year round.
tuber size
It is important that you do not miss the optimal harvest maturity. If you wait too long because you are still hoping for a few centimeters in circumference, the tuber will already begin to lignify internally. They can burst open, become spongy and lose their sharpness with each passing day of overripeness.
The optimum degree of ripeness should be reached no later than six weeks after sowing. Classic signs of maturity are a tuber size between two and three centimeters. As soon as a radish plant stands out among the others with its largest leaves, you should check the tuber size on the specimen daily.
maturity test
The best way to find out whether your radishes have really reached the perfect level of ripeness is to do a bite test. To do this, hold a bulb in one hand and the petiole in the other. Now turn both hands in opposite directions until the stalk snaps off the tuber. Rinse the tuber briefly under cold water and bite into it. If it is crisp and tastes aromatic and hot, it is ready for harvest and you should harvest all other radishes with the same tuber size as soon as possible.
If the tuber is still too hard, you should carry out the bite test daily until the desired degree of ripeness is reached.
harvest time
It is advisable to only harvest radishes in the late afternoon. At this time, the vitamin content is highest and the nitrite content is lowest. This is due to the fact that the nitrite is mainly stored in the plant tissue due to the sunlight. The vitamin content is also influenced and boosted by sunlight. In the evening, this drops again and nitrite moves into the tuber in a significantly higher concentration.
overripe
If you missed the perfect time to harvest and the bite test showed a spongy, soft consistency, then the tubers are overripe and only partially suitable for tasty consumption. However, you do not have to harvest the overripe Raphanus sativus var. sativus, you can simply leave them in the bed or in the vegetable box. In the period that follows, the tubers lignify and pods form. If these have reached a light brown discoloration, they contain germinable seeds inside. You can dry them until the following year and then use them for sowing.
harvesting technique
With radishes, half of the tubers grow in the ground. The upper half grows above the surface of the earth. Since they are flat-rooted, they sit relatively loosely in the ground and can be pulled out easily. To do this, grasp the leaf stalks and pull on them vigorously. Avoid breaking the stems by holding them together. This distributes the pressure and you can also withstand a stronger pull if the soil is very compact and firmly encloses the tubers.
TIP: If you moisten the soil before pulling out, the tubers can be removed even more easily.