Compost is certainly the most valuable and easiest to use fertilizer the gardener has available. It is inexpensive because you can make it yourself. There is also no risk of over-fertilization. What should you pay attention to when fertilizing with compost?
How do you properly fertilize plants with compost?
The best way to fertilize with compost is to spread a kilo of compost per square meter of soil and rake it in lightly. Use fine-crumb, sifted compost soil, avoid acidic or lime-rich compost types for sensitive plants such as azaleas and rhododendrons.
Fertilizing with compost – when and how?
You can give compost all year round. In spring, the compost soil is spread generously under the plants and - where possible - lightly raked into the soil. Fertilize as needed as the year progresses.
There is no risk of over-fertilization with compost. However, you shouldn't overdo it. As a rule of thumb, you should not exceed one kilo of compost per square meter of soil.
Which plants should you not fertilize with compost?
There are a number of plants that are better cared for without compost. Compost can be very acidic or too rich in lime. You should not fertilize with compost:
- Azaleas
- Rhododendrons
- Meadow plants
- Plants without high nutrient requirements
Provide compost as a starting aid
When planting new trees, shrubs and heavy feeders, you should improve the planting substrate with compost before planting. Work the humus into the soil.
Sift compost before fertilizing
It is a good idea to sift the mature compost before use. To do this, use a grid (€29.00 on Amazon), which you set up at an angle and pour the compost through.
Sifting creates a particularly fine, crumbly soil that is ideal for young plants.
If you want to use potting soil made from compost, you should steam it first. This destroys pests, weed seeds and fungal spores that could harm the seedlings.
Improve acidic compost with lime
Acidic compost is created by excessive amounts of lawn clippings and leaves. In this case, you can amend the compost with lime to increase the pH.
But it's better to have the soil examined in the laboratory first. It is not possible for a layperson to determine the nature of the soil.
Tip
You should not use compost that contains materials such as ash, cat litter or citrus fruits for vegetable or fruit plants because of the pollutant and pesticide contamination. This compost is only suitable for flower beds or lawns.
