Raised beds
Warm, fertile and ergonomic
Raised beds are becoming increasingly popular in gardens. This is hardly surprising, as their special design promotes plant growth, leads to earlier harvests and significantly reduces the number of snails. The concept is also ergonomic: you don’t have to bend over or kneel down and can garden comfortably while standing.
Advantages of raised beds
- The decomposition of organic materials inside the raised bed generates heat from below. This promotes the growth of heat-loving plants such as peppers, courgettes and tomatoes.
The resulting humus soil provides the plants in the raised bed with the best possible growing conditions. Once all the material has decomposed, the soil is spread around the garden and the raised bed is rebuilt.
- Recycling all valuable and healthy garden waste in your own garden.
The raised design makes gardening easier.
- Because the filling material settles over time, the bed is topped up with compost every year. This leads to a welcome revitalisation of the soil.
Creating a raised bed – how to proceed
A raised bed is constructed from various layers of biodegradable material. As this material decomposes, heat is released, increasing the soil temperature by up to 5°C compared to a flat bed. This results in faster growth and an earlier harvest.
Time and location
- The raised bed should be constructed in autumn or very early in spring.
- To make optimum use of sunlight, you should lay out the bed in a north-south direction.
- Dig a pit 20–30 cm deep and approx. 150 cm wide and keep the turf.
Construction
- First, build a wooden frame to the desired height.
- It is advisable to line the inner walls with plastic sheeting. This extends the durability of the wood and prevents drying out and evaporation.
- To keep voles out, you should line the bottom with a fine-mesh wire grid.
- Instead of a raised bed, you can also create a mound bed: it is constructed using the same materials, but is piled up on the ground in the shape of an elongated mound.
Filling the raised bed
- The inner core of the raised bed is constructed using shredded branches and twigs, hard pieces of stem and similar material. This ensures good ventilation of the bed and promotes the decomposition of the layered material.
- Now place the grass sods that you set aside earlier on top of the wooden core with the green side facing down. Alternatively, coarse garden waste, grass clippings or straw are also suitable.
- Next, add a layer of mixed leaves approximately 30 cm thick, which should be moist. However, do not use leaves from oak or walnut trees.
- Next, add a layer of coarse compost approximately 15 cm thick.
- Finish with a layer of fine compost and/or garden soil approximately 25 cm thick.
- Sprinkle Oscorna Soil Activator generously between the individual layers.
How to plant your raised bed
Experts recommend mixed cultivation
Whether through root secretions or scent, plants can protect and promote each other. Planting herbs between vegetables not only repels pests, but often improves the flavour as well.
Oscorna gardening knowledge “Mixed cultivation”
> Finding good plant partners
Timing is everything
In the first two years, the fresh raised bed contains the most nutrients.
For this reason, heavy feeders such as tomatoes, cabbage, celery, leeks, cucumbers and courgettes are ideal for growing. These will then thrive and grow strong. Light feeders such as herbs, peas or beans should therefore only be planted in the third year.
When the raised bed has collapsed after about 6 years due to rotting, you can continue to use it as a bed.
How to fertilise your raised bed
A newly created raised bed that has been layered according to our recommendations (> Creating a raised bed – how to do it) contains sufficient nutrients, meaning that no additional fertiliser is required in the first year.
From the second year onwards, we recommend fertilising with Oscorna-Animalin garden fertiliser and improving the soil with Oscorna-BodenAktivator.
| Application | Oscorna-Animalin garden fertiliser |
|---|---|
| Main fertilisation: | Heavy feeders 120 g/m²; medium feeders 100 g/m² |
| Re-fertilisation: | Heavy and medium feeders with half the application rate during the growing season |
| Main period of use: | February to November |
| Package size: | 1 kg / 2.5 kg / 5 kg / 10.5 kg / 20 kg |
| Application | Oscorna Soil Activator |
|---|---|
| Once a year in spring*: | 200 g/m² |
| Package size: | 3 kg / 5 kg / 10 kg / 25 kg |
*If you do not compensate for annual soil depletion in raised beds with compost, but use unfertilised soil instead, we recommend a second application of Oscorna Soil Activator at a rate of 200 g/m² during the growing season.
We recommend growing low-nutrient plants only after the raised bed has been in place for three years. No additional fertilisation is recommended here. Soil improvement with Oscorna Soil Activator (200 g/m²) covers the nutrient requirements for low-nutrient plants such as herbs, beans or peas in raised beds.
Heavy feeders and ascetics
The requirements of individual vegetable varieties vary greatly. Some need “concentrated feed”, while others are content with modest meals.
Vegetable varieties are therefore divided into three groups, for example:
| Heavy feeders | Medium feeders | Light feeders |
|---|---|---|
| Cabbage varieties such as red cabbage, white cabbage savoy cabbage cauliflower Brussels sprouts Chinese cabbage Cucumbers Potatoes Leeks Celery Pumpkin Courgettes Tomatoes Rhubarb |
Onions Garlic Carrots Beetroot Fennel Lettuce varieties Spinach Salsify Radishes Kohlrabi Peppers Melons |
Beans (legumes) Peas (legumes) Herbs |
When fertilising raised beds, please note that fertiliser should only be applied after germination in the case of seed crops. For plant crops, fertiliser can be applied at the time of planting.
If, contrary to our recommendation, you fill your raised bed with unfertilised soil instead of coarse compost, we recommend fertilising the crops and improving the soil with Oscorna Soil Activator from the outset. Low-nutrient plants can then be grown from the first year onwards.