Choosing the right compost needn’t be a challenge. Follow Amateur Gardening’s easy-to-understand guide and your garden will be bloomin’ lovely!
The best all-rounder. Once called ‘universal’ compost, these mixes cater for a host of uses – including sowing large seeds, pricking out seedlings and planting-up pots, containers and hanging baskets. Don’t use it to sow small seeds though: choose a seed compost (see no. 4, below). Go for a quality brand of multi-purpose such as Miracle-Gro compost or Levington. Expect bags of multi-purpose to contain around 40-70 per cent peat.
Peat-free multi-purpose compost
Peat is widely regarded as one of the best compost ‘ingredients’ for raising plants. In recent years, concern has escalated over its use, with a growing band of gardeners arguing that peat is best left in bogs, which are considered to be important wildlife habitats. A decade ago, early peat-free composts were dire – but today’s eco-friendly mixes have come on in strides, although extra care may be needed with watering and feeding. For best results, opt for a bag from a well-known manufacturer. As well as the Miracle-Gro peat-free shown here, those made by New Horizon have won applause from gardeners, too. Peat-frees can be used for the same tasks as multi-purpose compost, above 1.
High-peat multi-purpose compost
Many gardeners swear by peat, with some arguing that it is a renewable resource. It’s light, free-draining and is an excellent growing medium for plants. To meet this demand, manufacturers are introducing more high-peat multi-purpose composts, which should offer great results. Incredicompost (80 per cent Irish peat and 20 per cent wood fibre) is new from Thomson & Morgan for 2015, although it’s only available by mail-order. It’s a premium multi-purpose that’s ideal for pot and container plants, and comes with a sachet of fertiliser. An established high-peat blend is Westland’s Jack’s Magic, which can be found at garden centres nationwide. It’s another good all-round compost.
Sowing seeds compost
Choosing the right compost to make your seeds burst into life is critical. That’s why we recommend a seed compost for germinating seeds, especially small ones. A good seed compost will coax flower and vegetable seeds into life; helping young seedlings to develop strong roots and healthy growth. Most seed composts work well for rooting cuttings, too.
Pricking out – Seedling compost (John Innes No.1)
Once your seeds have germinated and are growing well, you’ll need to prick them out them out before they become leggy (tall and spindly). You can use multi-purpose, but a low-nutrient seedling compost is better, and is ideal for cuttings that have rooted. A good seed compost will contain sufficient nutrients for the first two to four weeks of use. You’ll notice that a lot of composts have the name ‘John Innes’ on the bag. John Innes is a formulation that was developed over 60 years ago and comprises heat-treated loam, sphagnum moss peat, horticultural sand and fertilisers. The exact blend depends on the product you’re buying, but the mixes make such composts perfect for specific gardening tasks.