For peat's sake!
For those of a certain age, and I include myself, the late Geoff Hamilton was the figurehead of BBC gardening. He was especially passionate of the need to halt the use of peat-based products, for good reason, he felt it was unnecessary for gardeners to endanger natural peat bogs to grow plants.
Yet over quarter of a century later, peat remains a key constituent to most UK composts while the case against peat has escalated to focus on its contribution towards global warming.
Why is the horticultural industry reluctant to switch to alternative products? Peat is undoubtedly a brilliant gardening product. It is a uniform, free from pests and diseases, gives good aeration at the roots while being able to retain large amounts of water. It is clean to handle and tactile making it pleasant to work with and one that gardeners have mastered the art of using to produce great looking plants. It is naturally nutrient-poor, making it possible, by adding the correct proportions of fertilizer (and lime), to produce a multitude of commercial compost mixes to suit any plant. No wonder peat is so popular, so what’s all the fuss about?
Many of today’s peatlands were formed around 10,000 years ago. They comprise semi-decomposed plant and animal remains, that are very acidic and waterlogged. This produces a special environment for distinctive plants and animals, yet is inhospitable to most micro-organisms. This means rates of decay are slow and peat gradually accumulates. In so doing, the peatbog forms a massive deposit of thousands of years of the greenhouse gas, carbon dioxide. Globally, peatbogs cover 3% of the Earth’s surface, yet hold as much stored carbon as all the world’s forests combined. Critically, once peatlands are damaged, through drainage and extraction, decomposition rates accelerate and carbon dioxide is leaked into the atmosphere, contributing to climate change.
Fortunately, peat-free alternatives make good replacements although unfortunately still hard to find. These comprise composted garden waste, pine bark, dried sewage sludge and coir. Coir is the leading product from the thick fibrous husks that surround coconuts. Like peat, coir is very absorbent yet able to maintain a high air content. Westland’s ‘New Horizon’ compost is perhaps the most readily available peat-free compost, while MiracleGro, Levington and SylvaGrow all offer alternatives. However, be warned...
In my experience, if 'peat free' is not emblazoned across the front of the bag then it's almost certainly not peat free.
In 2011, the government set voluntary targets to end sales of peat-based compost for domestic use by 2020. This dramatically failed, leading to the current cohort of celebrity gardeners protesting loudly. It is certainly unacceptable that peat-alternative composts remain hard or impossible to find in garden outlets despite the ‘writing on the wall’ for horticultural peat, so if you can’t find any at your local store make sure you ask: ‘Why not?’