To add the the confusion there is soilless compost that usually contains sphagnum peat moss, coir, vermiculite and sometimes perlite. is made from rotted waste materials such as plant foliage and stems, vegetable and fruit waste, grass cuttings and cardboard and paper. It’s perfect as a soil improver. Do use fresh compost each year to pot up your existing and new plants as this minimises risk of pests and diseases being carried over. It will also provide fresh nutrients to replace those that have been used up.

Used on it's own,loam would be totally unsuitable for growing in pots - much too dense, it would 'slump' or compact in the pot, excluding the air that plants roots need. So we add things to the loam to give us the desired results we need. The John Innes recipe called for sphagnum moss peat but we prefer not to use peat. Its use is controversial to say the least and, rightly or wrongly, environmentalists will lobby government to ban its use all together. That process hasstarted already and is well under way. So, instead of peatwe use a peat-free compost. It is actually manufactured by one of the large commercial compost manufacturers and is based on coir (coconut husks), recycled wood waste and composted bark. We have tried it on its own but results were poor resultsalthough others report excellent success with it. John Innes Potting Composts (Soil Mix and Fertiliser Base)– best for established plants and general use Loam (or soil) obviously varies from area to area - you can probably tell that from your own garden. The original J.I. requirements were for a medium clay loam, stripped from grass ley (established pasture). Now, I suspect that mostmanufacturers use a sandier soil, but clay is the magic ingredient. It is mainly the clay fraction that provides and holds on to nutrients and retains water. But clay is heavy (gardeners talk about a heavy clay soil and it is physically heavier) and can be difficult to handle, especially if it's wet.Loam requires to be sifted before use to remove stones etc. and wet clay is impossible to sieve.

What are the different types of John Innes used for?

There are several different common John Innes composts, or potting media that are on the market today. These are: This is derived from volcanic glass and is mainly used added to compost for growing cuttings as it retains a certain amount of moisture but also opens up the compost structure and so avoids compaction and water-logging. It also has excellent thermal properties so that the compost doesn’t swing between temperature extremes which can retard growth. Perlite can also be used alone for rooting cuttings. Also if considering a green roof where weight is an important factor combine a percentage of Perlite as it is extremely light. No. 2 contains moderate nutrient levels, and is used for growing established plants and most vegetables. [1] The base soil is amended with: John Innes Compost No. 2– for transplanting young plants or plants that don’t thrive in rich soil like thyme However, you wouldn’t use garden compost for seed sowing or to root cuttings (it has too many nutrients) and its bulk would make it quite heavy for hanging baskets. If you want to turn it into potting compost, it’s important to mix it with other things – sand, grit, topsoil or leafmould. See advice on container growing and how to make peat free potting composts. Potting composts

But it is important to remember that there are certain plants that need a different formulation, that is more free draining or which contains a specific mix of nutrients. This is a loam compost with reduced peat mix. It is specially designed for lime-hating (acid-loving) plants. Those who are trying to avoid harmful practices and want to garden as sustainably as possible should aim to avoid choosing products that contain peat, non-sustainably sourced loam, and any non-organic fertilisers or other problematic ingredients.This has twice as much nutrients as the No 1 and is used for more established plants such as container grown vegetables which don’t require large amounts of fertiliser, spring and autumn bedding plants and houseplants.

Coir: Also known as coco coir, or coconut fibre, this material is made from the pith and/or outer husks of coconuts. It’s a long-lasting and effective growing medium, helping to keep soil aerated and moist, and is often used as a substitute for peat. READ NEXT: Our roundup of the best composts you can buy What are some common compost ingredients and terms to be aware of? These soils are the best soils for gardeners. They combine the best qualities of different soil types and are great for plant growth. This type of loam based compost is used for young plants, cuttings that are rooted, and seedlings (potted up). John Innes Compost No.2 So many people are familiar with John Innes media, and know how to use it, very few will actually know what it is or why it is named such. Some people believe there is a company named John Innes, others believe that it was invented by a horticulturist called John Innes, but neither is true.This growing medium contains coir, propagating bark, Melcourt’s proprietary Growbark, and enough nutrients and fertilisers to keep your seeds happy for around six weeks.

The completed mix then needs time to ‘mellow’ for around two weeks; this allows the nutrients and lime to be absorbed onto the loam and organic material. Ideally the mix should then be used within three months. This normally gets put over the soil and it’s a precious commodity because most of us can’t make enough for the wholes garden. It needs to spread in autumn, round precious plants, and then it’s pulled down by earthworms. It’s good garden sense because leaves can’t be added to the compost heap the lignin in the leaves is hard to break down. The amount of lignin varies. Beech leaves take longer to rot than many others because they’re high in lignin. Turning your leaves three or four times a year speeds up the process and should produce friable leaf mould within a year. Once cooled, the topsoil then needs to be mixed with moss peat to increase the permeability, aeration, and the water and nutrient holding capacity. Alternatively, more environmentally friendly forms of organic matter can be used such as coir (coco / coconut fibre) or fine bark. This should then be followed by an addition of sharp sand (or grit). The ratio of the mix should ideally be 7:3:2 topsoil:peat:sand. If a large volume of growing medium is being produced then a cement mixer will assist with the mixing process. Sand - The coarse sand or grit is used as a physical conditioner to allow excess water to drain from the compost and thus prevent water-logging. It also helps to provide stability for larger plants.

Soil improvers and other materials

This mix contains double the amount of nutrient in John Innes No 1 to suit established plants. It is suitablefor most houseplants and vegetable plants in containers. Again, you can easily recreate your own peat free potting mix, see how to here. Soil improvers and other materials Commercial composts of this type, either John Innes composts, or composts with ‘added John Innes’ should have been specially formulated to allow for good drainage, aeration, fertility and optimal plant health and plant growth. Loam: While most composts don’t contain soil, certain types, such as John Innes composts, will contain loam. Loam soil is notable for its particular proportion of minerals: a roughly 40-40-20% blend by weight of sand, silt and clay, which give it excellent water retention and drainage, as well as making it easier to till. Loam soil is also generally rich in nutrients, and soil organic matter such as humus. Melcourt has been producing bark-based, peat-free replacements since the early Eighties. Many commercial nurseries use the company’s composts as a growing medium. It’s been successful for me, although containers of spring-flowering bulbs haven’t done as well. The bags are sizeable because wood-based composts are light. SylvaGrow multi-purpose compost with added John Innes is peat-free and contains no green waste. It scored highly in a Which? Gardening trial in 2017. melcourt.co.uk, 01666 502711. Wool based