Improve hard clay and nutrient-poor soil.

In order to have beautiful flowerbeds and abundant crops of vegetables, fruits, and berries, good soil is required. But what does that really mean? Well, it means that the soil is porous, has a good structure, a rich microorganism life, and contains a moderate amount of nutrients, acidity, and water. By regularly adding compost, manure, and other organic plant materials, microorganisms, earthworms, and humus content (i.e. the amount of decomposed material) will greatly benefit. Nutrients that plants need will be released and the soil's ability will be improved.

Every time you harvest, a part of the nutrients in the soil disappears, which is why it is important to give back nutrients. That's exactly what you do when you fertilize with compost, bokashi or organic fertilizer. All soil benefits greatly from this, but it is especially important for the slightly more demanding clay and sandy soils.

If a soil is poorly drained and too clayey and compact, it means that it lacks airy pores and earthworm tunnels that can absorb rainwater and hold onto it for a while. Sometimes the problem is so obvious that you can see it on the surface - in the spring, water does not drain away and in the summer the soil is dry with cracks. In such soil, it is difficult for roots to grow - they prefer a porous soil, somewhat like a sponge. However, clay soil contains a lot of nutrients and can therefore be a good soil if you mix in plenty of compost, bark mulch, and other organic materials, such as manure, bokashi, crop residues, grass clippings, etc. Cover cropping, which involves adding layers of different plant materials, such as grass and leaves, also helps to eventually improve the porosity of clay soil of the poorest quality. However, you should not mix in sand - as this can eventually result in a concrete-like texture.

In a pure sand soil, there are few or no soil aggregates (small clay particles), and it also lacks pores to hold onto rainwater and nutrients – everything quickly drains through. The sandy soil thus often becomes nutrient-poor and dry. However, sand also has its advantages: For example, it maintains a more consistent temperature and is less prone to weeds than clay soil. To improve the properties of sandy soil and make it contain more soil aggregates and pores to hold onto nutrients and water, you can do the same as with overly compact clay soil; simply add organic material and cover crops – this builds up the humus content in the soil. You can also lay layers of grass on sandy soil and water with compost tea or nettle tea – this helps improve the soil for planting in the long run.,,Image: Liselotte Roll

The magic lies in the plant material - nothing promotes soil better - regardless of the starting point. In addition, the organic material develops food for microorganisms and earthworms that further improve the structure of the soil and that control harmful organisms and diseases.

Compost material - preferably half decomposedManureBokashi - significantly increases the number of earthwormsGrass clippingsPlant residues from the gardenLeavesBark mulch

There are also green plants that can help improve the soil. If you have hard clay, you can, for example, use comfrey or common yarrow. They have strong roots that help break up the soil. They are also very popular among bees and bumblebees. Tips: If you have very difficult soil and do not want to improve it, it can sometimes be easiest to grow vertically, for example in raised beds or using the "No dig" method.

Liselotte Roll, Swedish garden inspirator, journalist and author of books about nature, cultivation and animals, such as "Earth", "Cultivate for Insects" and "Chickens as a Hobby". (Photo: Sandra Birgersdotter Ek)