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January: plant your raised bed
Whether you opt for an old piano, a modern high-tech all-in-one solution or a popular DIY pallet raised bed – there are many different possibilities for external design. And yet it’s the content that counts, as a raised bed offers fertile soil for vegetables, herbs and flowers.
As a rule, raised beds are 70 to 120 centimeters high so that the working height is easy on the back. A grid of hare wire separates the soil from the ground and protects against voles. The bed box is then filled with coarse twigs and branches up to a depth of about 20 to 30 centimeters, followed by 15 to 20 centimeters of chaff, i.e. small shredded wooden cuttings – this serves as an organic drainage layer to prevent waterlogging.
The right amount of nutrients is then incorporated into the bed by means of a 20- to 30-centimeter layer of coarse raw compost, which has not yet completely decomposed. The raw compost also establishes the ideal conditions for earthworms, which help amateur gardeners to keep the soil loose and rich in oxygen. Finally, soil is mixed with rotting compost, and the bed box is filled up to the top – your raised bed is ready. If you don’t want to have to wait until January, you can plant your raised bed in the fall. The advantage at this time of year is that it is easy to find enough green waste that is suitable for the bottom layers.
February: leave nature to do its work
Ideally, you should wait a few weeks between filling and planting the raised bed so that the contents can settle and composting can begin – this provides a nutrient-rich environment. The biggest advantage of a raised bed is that due to the decay of the lower layers, heat develops in the raised bed even during the cold months of the year. Amateur gardeners who integrate a cold frame attachment, which turns the raised bed into an elevated greenhouse and protects seedlings and seeds from frost, can start to weed and shovel their raised bed in late February or early March.
March: bring the first plants to life
In the first year, you should opt for plants with a high nitrogen uptake that can cope with the rich nutrient content of the freshly planted raised bed. Tomatoes, peppers, celery, cucumbers, cauliflower, red cabbage and eggplants can be planted in February or March under the protective cold frame glass. A growth fleece placed between the top frame and the young plant gives added protection against cold and excessive sunlight.
But it’s the right neighborhood that counts:
- Tomatoes, cauliflower, red cabbage and celery get on well with each other and thrive alongside one another.
But never plant two types of cabbage together, as they compete for nutrients.
- Cucumbers and eggplants don’t like being in direct proximity to tomato plants, so they should be planted at the other end of the bed. The same applies to eggplants and peppers.
- Cucumber and celery go well together.
Tip: if you prefer flowers to vegetables, again you should choose plants with a high nitrogen uptake such as sunflowers, asters, chrysanthemums, small citrus trees, geraniums or tulips.
April: plant your vegetable garden to your heart’s content
More cold-sensitive plants with a high nitrogen uptake such as fruity strawberries, carrots, kohlrabi, beetroot, radishes and zucchini can now be added to a glass-protected raised bed. The right neighborhood remains just as important:
- Strawberries appreciate proximity to radishes and herbs such as chives, garlic and parsley.
- Carrots thrive particularly well near cucumbers and beetroot.
- Kohlrabi has no problem with being close to tomato plants.
But watch out: zucchini grow quickly and easily, but should be planted carefully in raised beds, as this plant from the pumpkin family spreads extremely quickly.
May: open-air at last
“You’re never safe from night frost until after St. Sophie’s day” – this old country belief is still observed by farmers and gardeners today. From mid-May, once the “Ice Saints” have passed – including St. Sophie’s day on 15 May – amateur gardeners can finally discard the cold frame on their raised beds. The young plants now get enough warmth day and night to develop freely without a glass roof, and there is no longer any risk of ground frost.
June: the first harvest
If you have not already pulled the first hot radishes out of the ground at the end of May, now is the time. After five months of care, worry and observation, the first harvest is now ready: cauliflower, cucumbers, strawberries, carrots, kohlrabi and zucchini are also ripe and will make the amateur gardener’s heart almost burst with pride.
July: protection against the heat on hot days
July is the hottest month of the year in Switzerland. There are a few tricks to provide natural heat protection, to make sure you will get a second harvest in your raised bed. You can protect the soil from drying out too quickly over the summer by spreading straw, grass cuttings or bark mulch around the plants up to a height of around three to five centimeters. However, because mulching removes nitrogen from the soil, you should fertilize regularly, for example with nettle liquid manure, dry coffee grounds or cold potato boiling water. You can also stretch an awning or garden fleece over the raised bed on particularly hot sunny days to protect the plants.
August: abundant watering
August is another hot month. The one thing you must never forget, especially on summer days, is to water your plants! There are also some other points to consider. To prevent the water from evaporating directly, and to protect sensitive plants from sunburn, water them early in the morning or in the evening when the sun is not as strong. For particularly thirsty specimens, such as tomatoes or potatoes, there is a little trick: dig small trenches around the plants so that the water flows directly to the roots and does not evaporate as quickly. What’s more, it’s better to water the soil directly rather than the whole plant, because tomatoes or cucumbers tend to develop disease and fungi quickly when the leaves are moist.
September: harvest and cook
The second big harvest is due in early fall: beetroot and celery will be ripe by now – if you have done everything right – and tomatoes, red cabbage, carrots, peppers, zucchini and cauliflower will produce bulging fruit again and again in a raised bed. You can preserve beetroot in vinegar to keep it for longer, cook tomatoes in aromatic sauce, prepare red cabbage for Christmas – and you will soon have filled your store cupboard with vegetables in preserving jars. However, you will quickly run out of space for all the zucchini, so you may find yourself simply giving them away to neighbors, friends and relatives.
October: plant winter vegetables
Even in the fall, there is still no end in sight to the growing season in a raised bed. The incorporated layer of raw compost continues to rot, develop heat and act as a built-in heater. The temperature in the raised bed is therefore about five degrees higher than in the open field. Since even young plants are protected from freezing frost, you can relocate seedlings from the raised bed and bring them into the house in October. Leeks, radishes and winter salads such as lamb’s lettuce grow quickly and can be harvested in the same year. You can plant all types of cabbage, onions and garlic now and harvest them in early spring.
When sowing winter vegetables, use the cold frame attachment or a foil tunnel – both of these store additional heat. You should only open the roof during the day to provide fresh air for the plants and stop them from getting fungal infections. On very cold nights, a fleece can give the plants additional protection and stop them from freezing.
November: a fresh winter harvest
Leeks, radishes and lamb’s lettuce are crisp and ready to pick. But watch out: never harvest at sub-zero temperatures, otherwise you will damage the plants and they may become mushy and inedible.
December: tender loving care for the raised bed
Unless you have planted cabbages, onions or garlic, which are not harvested until spring, your raised bed is now empty. Green manure represents real tender loving care for the soil. Plant your raised bed with hardy legumes (Fabaceae or Leguminosae) or clover (Trifolium), – this protects the soil from erosion, wind and weather, and binds the nitrogen in the soil, which is important for the new plants next year.
Conclusion: full speed ahead in the first year
Due to the different layers of soil and compost, the conditions in a raised bed are different from those in an open garden bed or balcony tub. Especially in the first year, amateur gardeners should stock the raised bed with plants with a high nitrogen uptake that appreciate the high nutrient content, which will allow them to develop magnificent fruits.
In the second and third seasons, you should mainly grow plants with a medium nitrogen uptake, which require fewer nutrients and less nitrogen. Fennel, leek, chard, radish, string beans, garlic and various types of lettuce are appropriate in the second year, for instance. In the fifth season, apart from a few site-specific plants with a medium nitrogen uptake such as strawberries or herbs, only plants with a low nitrogen uptake such as peas, lamb’s lettuce, rocket and bush beans should be added, as they have only low nutritional requirements. And before the fifth season, everything starts all over again. Then you will need to get the raised bed back into shape, change the filling and replant to your heart’s content.