Ericaceous compost is needed for plants that prefer an acid soil (a low pH) – like rhododendrons and blueberries. If you have alkaline soil then the simplest choice is to avoid growing these plants, as they will not thrive without special care – they struggle to take up the right nutrients in the right quantities in what is, for them, the wrong soil.
Alternatively you can grow them in containers in an ericaceous growing medium, but the commonly-available ones all contain large amounts of peat. Peat-free ericaceous composts are now available (often based on composted bracken), although you may have to source them via mail order.
To make your own ericaceous mixes you’ll need a pH testing kit or probe, so that you can ensure the pH is lower than 5.5. Garden compost tends to be slightly acidic, depending on what you add to it (onions and citrus peel will add to the acidity, egg shells reduce it), as are coffee grounds. You can also use composted pine bark, and coir.
Cocoa shells make a good mulch for acid-loving plants, but be careful if you have pets as they can be poisonous to some animals. You can also use pine needles and coffee grounds for mulching.
Sulphur chips are a way of lowering pH over time (over small areas). If you have the wrong soil then your mains water is likely to be too alkaline as well, so try and water acid-loving plants with rain water whenever you can.
Seed bombs are one of the Guerrilla Gardener’s tools of the trade – thrown onto vacant lots they contain everything a seed needs to grow except water. Once it rains the seeds germinate and grow and add a touch of nature to the urban environment.
Guerrilla gardening is not entirely legal. It involves taking care of someone else’s land, and if that involves trespassing then you could get in trouble. Throwing in a seed bomb is a low risk way of improving the area, but many guerrilla gardeners prefer to tend patches of neglected public land where the legal implications are more hazy.
Guerrilla gardening is now so trendy that you can buy ready-made seed bombs (and grenades!) but many of the older recipes for making your own still contain references to peat. It’s actually easy to replace the peat with peat-free compost. Seed bombs only contain three (or four) ingredients – seeds, a small amount of growing medium (and a sprinkle of fertilizer if necessary) and a clay shell to hold it together. You can buy clay powder to make that, or use your own garden clay.
The idea is to use a good, hard throw, so that the seed bomb cracks on impact, leaving Mother Nature to do the rest of the work for you. Wildflower seeds are often used, as they grow into plants that can take care of themselves.
For more information on seed bombs and guerrilla gardening, check out the Guerrilla Gardening website.
Carnivorous plants grow in peat bogs – the have evolved a taste for meat as an extra source of food in these nutrient-poor environments. These plants need peat to thrive, but we shouldn’t be digging up peat bogs (and these plants in their natural environment) just so we can grow them at home instead.
The easy option is not to grow them, and to visit them in the wild. If you do want to grow carnivorous plants then it is possible to buy reclaimed peat – peat that is collected from water than runs off peat bogs. It’s a waste product removed from the water, and the bogs are left unharmed. It is a renewable resource, available in limited quantities. You’ll almost certainly have to source it mail order, and it’s expensive. But if you’ve followed the rest of the advice in this book then you’ll have cut out all other sources of peat from your garden and cut down on the amount of potting compost you have to buy – so splashing out on this sustainable product to support your hobby won’t break the bank.