The importance of growing media in horticulture and landscaping
The UK uses over 4 million cubic metres of growing media each year. Roughly a quarter of that is used by professional growers to produce plants for the UK's parks and gardens, with the rest purchased by consumers for use in their gardens. Around 1,000 jobs in the UK are provided in the manufacture of growing media. Further along the supply chain, without high quality growing media for professional growers far fewer of the £1.3 billion of plants that UK growers produce would be grown competitively in the UK.
Changes in what's in growing media
For many years UK horticulture has been reducing its reliance on peat. Twenty years ago almost all the volume of growing media was made up of peat, and now the proportion is less than half. That's important, as peat is extracted from peat bogs, which releases carbon dioxide and impacts on habitats. Most peat alternatives are by-products of other industries. For instance coir (coconut husk) and wood fibre are byproducts of coconut farming and the timber industry. However they have their own environmental impacts such as carbon miles in transport to the UK. Availability of these alternatives can also be a challenge. Government subsidies for using wood fibre in biomass power generation as part of a moveaway from coal power stations means enough wood fibre isn't always available or affordable for use in growing media.
Moves to greater sustainability
The industry has developed a Responsible Sourcing Calculator for growing media. This assesses the different environmental impacts of different components of growing media, and generates a 'score' for how responsibly sourced a product is. Over time this will play a key role in educating consumers about the different considerations around sustainability, and driving choice for more sustainable alternatives. Work is beginning on extending this to providing carbon footprinting for growing media products, and on developing a strategy for further peat reduction.
Growing media - key facts and figures
You can read more about the facts and figures to do with growing media in this selection of research and statistics.
Transitioning towards peat-free growing media - this report from the University of Coventry examines progress towards peat removal from growing media, and examines the drivers and barriers to further peat reduction.