Lightweight, cheap and rot-proof even when damp, plastic is an incredibly convenient material in the garden. In the 60 years it has been in widespread use it has permeated every area of gardening, from seed trays and plant pots to horticultural fleece, hoses and fruit cage netting.
But the very qualities which make plastic so useful come at a high price to the wider environment. Plastic is among the worst pollutants of our oceans, devastating marine wildlife and washing up as unsightly rubbish on beaches. Changing the way we garden to avoid using plastic, by turning to biodegradable materials like wood, paper and coir and making careful choices, reduces the environmental cost of gardening – and sometimes it’s better for your plants, too.
Nine ways to reduce garden plastic
Here are some hints, tips and simple swaps that will help minimise the amount of plastic used when you're gardening.
Seed trays (HDPE) last well and are lightweight but once broken are difficult to recycle. Swap them for wooden or bamboo seed trays.
You can buy wooden seed trays or make them yourself from scrap wood. They are easily repaired, so last indefinitely when well looked after. Wooden trays are heavier and must be stored somewhere dry over winter. They need more watering, but it’s easier to re-wet dry compost as wood is absorbent so doesn’t let water run straight through as plastic can.
Bamboo seed trays give the look and feel of plastic and are lighter than wood. But they aren’t repairable and you can’t make your own.
Where to buy ►Burgon and Ball ►Great Dixter shop ►Suttons ►Haxnicks ►RHS online shop
Modules (PP or PS) are often flimsy and shatter easily; they are rarely recycled. Swap them for newspaper pots, soil blocks, toilet roll inners or pulp modules.
Buy biodegradable pulped cardboard modules or make them for free from newspaper or cardboard toilet roll inners (best for larger seeds). Plant seedlings without removing containers, which rot away in the soil.
Soil blocks are cubes of compressed blocking compost, shaped using a soil blocker; sow into the top and the seedling’s roots bind the compost into a natural module.
Home-made modules take time to make and need more frequent watering. But seedlings never suffer from potbound roots and establish more quickly.
Where to buy ►Bloomling (biodegradable modules) ►Nether Wallop Trading Co. and RHS Online Shop (paper potter) ► Ladbroke soil blockers (soil blockers)
Plant labels (PP) are easy to write on and reuse but break quickly and are difficult to recycle. Swap them for wooden lollipop sticks, bamboo plant labels, slate labels, copper or aluminium metal labels.
Buy lollipop sticks cheaply from craft shops; wooden plant labels are also widely available, though more expensive. You can also make your own by splitting thin pieces of scrap wood lengthwise.
Untreated wooden labels wick up water from damp compost, though, and writing becomes blurred, so they're perhaps best for short-term labelling such as vegetables sown in a greenhouse then planted out. Bamboo is less absorbent, so labels stay legible all season. Slate labels are expensive but handsome and easily reused; metal labels cannot be reused once engraved.
Where to buy ►Buddly Crafts (lollipop sticks), ►Nutscene ►The Garden Label & Sign Co. ►Alitags ►RHS Online Shop (wooden and recycled labels)
String and netting (PP, PET) are strong and long-lasting but rarely recycled; wildlife can become entangled in plastic netting, too. Swap for: jute or hemp twine, jute netting, metal mesh. Natural twine is readily available and kinder to plants than plastic ties as it won’t cut into stems. It needs replacing every couple of years. Jute pea netting looks beautiful but again, you can only reuse it once or twice.
To protect fruit and vegetable crops from birds, make individual cages from fine 1cm (½in) gauge galvanised metal mesh stapled onto wooden frames. It is more expensive and heavier but doesn’t tear like plastic can, so lasts many years.
Where to buy ►Quickcrop (jute netting), ►Suregreen (wire mesh) ►RHS Online Shop (jute twine and netting)
Plant pots (PP, LDPE, HDPE) are lightweight and cheap, but difficult to recycle once broken. Alternatives include terracotta, coir, fibre, Vipots, bamboo and waste cardboard.
Single-use biodegradable containers are widely available. They are not removed before planting, avoiding root disturbance, but this means they must be bought anew each year. Coir is made from imported coconut hulls, so has a high carbon footprint. It can also be slow to decompose in dry soil. Fibre pots, made of cellulose, break down more quickly.
Terracotta containers are handsome and last years, but they’re heavy and, like most of the biodegradable containers, dry out more quickly. Lightweight options, reusable for 3-5 years, include Vipots, made of rice and grain hulls, and bamboo. All are expensive, but you can make them for free: cut out 7cm (3”) square boxes from waste cardboard, tape together with paper masking tape, then plant.
Where to buy ►The Natural Gardener (coir pots) ►Nutley's Kitchen Gardens (fibre pots) ►Agriframes (bamboo pots) ►Tamar Organics (Vipots)
Compost bags (LDPE) can be reused as rubbish sacks but can be recycled only if cleaned first. You can avoid plastic use by making your own compost at home or re-using compost bags where possible.
Buying growing media in large quantities, as bulk bags or loose loads, cuts plastic use but requires space. One Kent garden centre, Edibleculture, sells compost in refillable ‘bags for life’, but remains the only retailer to do so.
Make your own potting compost by blending topsoil, garden compost, leafmould, grit and fertilisers in a bucket or wheelbarrow according to requirements. Home-made composts are more susceptible to weed seedlings and soil-borne disease, and it takes practice to get the mix right, but you can tailor it precisely to your needs.
Watering equipment (PVC, HDPE, LDPE) comes in multiple types of plastic, including vinyl (used in most hoses), linked to harmful toxins. Swap plastic for metal watering cans and water butts for galvanised troughs.
Hoses and automatic irrigation systems are exclusively made of plastic, so the only plastic-free alternative is to stop using them. Metal watering cans are heavier and watering takes longer, but hand watering uses water more economically and targets irrigation more efficiently – plus metal cans have a much longer lifespan than plastic ones.
When replacing rigid plastic water butts, galvanised steel cattle troughs make attractive alternatives. Stand on bricks and fit a tap into the drainage hole, then add a wooden lid. Troughs come in various sizes and are priced similarly to plastic.
Where to buy ►Haws (watering cans) ►Mole Valley Farmers and McVeigh Parker (troughs)
Glasshouse insulation and plant protection (HDPE, LDPE, PP, polycarbonate) includes bubblewrap, polythene cloches and woven plastic meshes and fleece which shred easily into fragments and cannot be recycled. Rigid polycarbonate contains the toxin bisphenol A. Plastic-free solutions include glass cloches, hessian and straw and cardboard insulation.
Glass tent or barn cloches are heavier than relatively flimsy polythene tunnels and stay in place better in bad weather. Though they are more expensive and can break, they usually last much longer.
Delay planting frost-sensitive plants to avoid using horticultural fleece and wrap tender plants such as bananas in hessian or newspaper stuffed with straw over winter. Lining greenhouse walls with cardboard also offers some insulation over winter.
Where to buy ►Hibbitt of Oswestry and RHS Online Shop (glass cloches)
Most gardening purchases come packaged in plastic, from mail order blister packs to fertiliser bottles. New plants also bring more plastic pots. Most is single use and difficult to recycle. Look out for plastic-free mail order nurseries, buy bare root plants and grow your own from seeds, cuttings and divisions.
Careful shopping choices help: fertiliser, for example, is often offered in cardboard boxes. Home-made fertilisers are also very effective. Some nurseries now wrap mail order plants in waxed paper or newspaper. Perennials, roses, hedging, fruit and wallflowers are available bare-root from autumn to spring; they are sold when growing conditions are at their best, though availability for perennials remains limited.
Raising bedding from seed avoids plastic plug trays and blister packs; you can also raise more unusual perennials, shrubs and even trees from seed, cuttings or divisions. It takes longer but can be considerably cheaper (and more satisfying!).
Where to buy ►Bluebell Cottage (plastic free mail order) ►Brookside Nursery, Unwins, Thompson & Morgan (bare-root perennials)
How to switch responsibly
A like-for-like exchange of biodegradable substitutes for plastic brings its own environmental cost. Firing and transporting heavy clay pots, for example, has a high carbon footprint and contributes to global warming.
Wherever possible, opt for home-made alternatives which reuse waste materials, and when buying, opt for sustainably sourced products and second-hand items available online or at auctions and salvage yards
What to do with existing plastic in the garden
Continue to reuse plastic pots, trays and other equipment until they reach the end of their useful life to keep them out of the waste system as long as possible. Compost bags can be put to multiple new uses as rubbish sacks, weed-suppressing ground cover or for growing new potatoes.
Once they need replacing, substitute for biodegradable alternatives and recycle spent rigid plastic wherever possible to keep the plastic in circulation. Many garden centres offer pot recycling collection points, and a few councils accept pots in kerbside collections. Larger municipal tips also accept coloured rigid plastic, but not black, as recycling equipment cannot ‘see’ black pigments.