Compost manufacturers have responded to the need to conserve our rapidly diminishing peat bogs, and there is a growing range of peat-free compost available.
What's in peat free compost?
- Wood and timber industry residues - Usually the primary ingredient in peat free compost, wood has a low pH and excellent drainage properties.
- Coconut fibre (coir) - A waste product from the coconut processing industry, buying coir will help the economies of many developing countries, although there are environmental costs to the long distances it has to be transported. Coir has excellent water and air-holding capacity.
- Green compost - Produced from garden and landscape waste from civic amenity sites. Microorganisms break down organic material into “humus” which can be used as a soil improver.
- Leaf mould - An invaluable ingredient in home-made mixtures, mature (two years old) leaf mould can be used neat for seed sowing, or incorporated into mixes to improve structure. However it can contain weeds and seeds.
- Garden compost - Home-made garden compost is nutrient rich. It is useful for potting on composts and long-term growing in containers. Timing of nutrient release can be very variable. It can contain weeds and seeds.
- Worm compost - Worm compost is ideal in mixes needing plenty of nutrients. It also has good water holding capacity, useful in hanging baskets.
- Manures - Well-rotted straw farmyard manure provides bulk and nutrients. It is best used in rich mixes for long term use, such as tomatoes or peppers growing in pots.
- Organic fertilisers - Bone meal, hoof and horn, seaweed meal and other organic fertilisers can be added to a mix to provide necessary plant nutrients. These are slow releasing materials, so large amounts are not needed.
What to look our for when buying peat free
- Make sure the bag says 'peat free'. If it doesn't, it probably isn't!
- Compost labelled 'environmentally friendly' or 'organic' may still contain peat
- A high quality peat free compost may cost a bit more
- Check the growing instructions to make sure you get the best results
What's the best way to use peat-free alternatives?
- Growing Seeds / Seed Sowing - Seed compost should be free draining and low in nutrients. Try using pure coir, mature leaf mould, or a mixture of leaf mould and loam.
- Potting on and growing cuttings - Use 100% coir to establish cuttings and pricked out seedlings. Feed the plants more frequently than with a peat mix. To boost nutrient and moisture retention add sterilised soil, leaf mould or green compost. To improve drainage add grit or sharp sand.
- Containers and hanging baskets - To make your own mixture, blend 50% coir with 50% home compost or leaf mould. Adding some bark-based compost will improve drainage. Adding manure gives a richer mix for greedy fast growing plants.
- Grow bags - Make your own mix by blending 30-40% garden compost or leaf mould into a bag of coir or bark/wood based proprietary product. Peat-free grow-bags are sometimes available.
- Soil Improvers - Soil improvers add organic materials to the soil, helping to boost soil biodiversity, nutrient level and improve moisture retention. Although frequently used as a soil conditioner, peat is fairly useless for this as it contains few nutrients. Composted organic products are much better.