How to use compost correctly

The compost is highly nutrient-rich, so follow the instructions on this page for best results.

Use of compost
Compost is great for general soil improvement and as a fertiliser, especially for perennial plants such as perennials, shrubs and trees.

Quantity and frequency:

• Apply a layer of 4 cm every 3-5 years or about 1 cm annually.
• A 1 cm layer is equivalent to applying 10 litres per m² or 1 m³ per 100 m².
• If you use compost for sowing, the compost must be incorporated into the soil before sowing.
• When planting, compost can be applied to the soil after planting. However, on clay soils where soil improvement is needed, it is recommended to incorporate the compost into the soil before planting.
• Compost or mixtures with compost should never be incorporated deeper than:
  • 20 cm on clay soil
  • 40 cm on sandy soil

Never sow or plant directly in unmixed compost.

When the nutrient status of the soil is in balance (possibly examined by a soil analysis), compost can replace phosphorus and potassium fertilisers and liming. This means that it is not necessary to use NPK artificial fertiliser. Only nutrient-demanding or fast-growing plants need extra nitrogen in the same year that a 4 cm layer of compost is applied.

With a small annual application of compost, it may be necessary to supplement with nitrogen. This can be done by using lime or calcium ammonium nitrate (e.g. 2 kg per 100 m²) or by mowing down nitrogen-fixing plant species such as ground clover or winter vetch.

If compost is applied regularly, there is no need to use sphagnum for general soil improvement. Compost is the most effective soil conditioner, especially in clay soils.

Kitchen garden and summer flowers:
Incorporate a 4 cm layer of compost into the soil before sowing/planting or spread on the soil after planting. Supplement with nitrogen fertiliser.

Old perennial beds:
Place a 4 cm thick layer of compost on the soil around the plants.

Landscaping your lawn:
Thoroughly and evenly incorporate a 3 cm layer of compost into the soil before sowing. Supplement with nitrogen fertiliser after emergence (but not during the winter months).

Planting perennials and small shrubs:
A 4 cm thick layer of compost is incorporated into the soil before planting or spread on the soil after planting.

Planting larger shrubs and trees:
The soil from the planting hole can be mixed with compost (1 part compost to 4 parts soil). Avoid putting unmixed compost in the bottom of the hole. After planting, spread an 8 cm thick layer of compost on the soil around the plant, but make sure to leave an area of bare soil close to the stem of the plant.

Old shrubs and trees:
Place an 8 cm thick layer of compost on the soil under the plants, but leave bare soil all the way around the stem.

Old lawns:

• Mix 1 part compost with 2 parts sand.
• Spread the mixture in an even layer of about 1 cm over the lawn in spring.
• Tear gently afterwards.
• If the grass is covered with the mixture for more than 1-2 weeks, you should water the lawn.

Greenhouse and houseplants:
Mix 1 part compost with 2 parts sphagnum before sowing or 1 part sphagnum before transplanting. Use unfertilised, non-calcified sphagnum.

How garden waste becomes compost at BOFA
Garden waste from both private and commercial customers is received and processed at BOFAa's facility in Rønne. Here, the waste is first broken down and then placed in compost bins. During the process, the windrows are continuously turned and watered to ensure efficient decomposition.

The temperature in the compost heaps rises to around 70-80ºC. This high temperature ensures that slugs and snail eggs do not survive, making the compost pest-free.

After about a year and a half, the garden waste is transformed into nutrient-rich and strong compost, which is distributed free of charge to the citizens of Bornholm.