The world’s climate change conference in Glasgow, COP 26 has been put back a year thanks to the coronavirus pandemic, but the looming climate crisis can’t be postponed.

We gardeners can continue doing our bit to help. As I’ve been outlining here since January, what we buy and how we garden will reduce carbon and other damaging emissions.

It’s estimated that global soils store three times as much carbon as the atmosphere and all vegetation combined. And that’s where we need to keep it.

Firstly, only use compost or soil conditioner that does not contain peat. Peat bogs sequester 10 times more carbon per hectare than any other land, including forests. We’ve destroyed much of our Scottish peat bogs to service the horticulture industry and are now importing fresh supplies, especially from eastern Europe.

The horticulture industry has fought hard against plans, introduced in 2011, for phasing out the use of peat. So as well as shunning peat compost, gardeners should support enlightened nurseries that use peat alternatives and demand plants and seedlings grown in this way.

Our garden soil also sequesters much more CO2 than had previously been thought and a recent study by Leicester University found that ploughed agricultural land contained much less carbon than undisturbed soil because ploughing had released it into the atmosphere. I’ve been delighted to see that my conversion to ‘no dig’ gardening not only saves my back but is recommended by modern research.

Digging the garden breaks up a complex, but invisible, fungal community, including mycorrhizal fungi that have a symbiotic relationship with plants. These organisms very slowly break down decaying vegetation, a process that’s continued by bacteria. But digging brings bacteria closer to the warmer surface and they respond to the warmer soil by working more quickly and releasing more CO2.

Lawn management also matters. Natural grasslands are brilliant carbon sinks, and while we can’t mimic that in the garden, less frequent mowing all or part of the grass helps. Five years ago, during a study of two Swedish golf courses, researchers found that frequently mown fairways emitted significant amounts of CO2 while the root systems on the rough sequestered carbon.

The study of the golf course greens also highlighted the damaging effect of lawn fertilisers. This was echoed last year by David Wolfe of Cornell University who explained that the production of every tonne of nitrogen fertiliser releases 4-6 tonnes of carbon.

Since these fertilisers deliver much more nitrogen than our grass or other plants can use, soil microorganisms convert excess nitrogen into nitrous oxide, N2O. This gas has 300 times more heat-trapping ability than CO2. The lesson is clear. If you’re concerned about climate change, don’t use synthetic chemicals in the garden.

Concerned gardeners want to cut back on plastic products as well. Discarded plastic chokes the seas and kills many of its inhabitants. Emissions from extraction, production, distribution and disposal of plastic are currently estimated to be almost one billion metric tonnes of CO2.

More alternatives to plastic are becoming available to gardeners: let’s use them. Gardeners can also combat the climate emergency with plants that absorb and store carbon from the atmosphere. All perennials do this, none more effectively than trees. Even if this carbon absorption largely stops at maturity, trees safely sequester it, unless, like Sitka spruce plantations, they are felled.

To a lesser extent hedges also do this and, like trees, provide shelter, shade and a cooler environment for us during hot weather. They reduce the effects of gales and torrential downpours and the noise and air pollution in towns and cities. By acting together, gardeners can make a significant difference in the climate

change war.