The first cool mornings, the sweet rot of fallen apples, the sight of seed heads – these are all signs that autumn is here. But what happens when it starts coming earlier? When the floor is littered with burnt leaves, when the summer crops give up early and the flowers fade before all the pollinators get their fill? What has happened is a “false” autumn .
The leaves on the ground of your local park and pavements are not autumn leaves, where a deciduous tree has reclaimed as many valuable chemicals as possible from the leaf, so that the colours beneath are exposed, before sending it to ground. The extraction of pigments in a leaf is a slow process that takes trees several weeks, but the blast of extreme heat stole this from the plants and instead they had to slough off resources as they struggled to stay hydrated. These are the leaves we see right now: brown, curled and fried by the sun.
There is a knock-on effect for these plants and their surrounding community. In some plants these reclaimed resources are stored – in dahlia and potato tubers, for instance – but in others, particularly deciduous ones, the resources are shared with others through complex fungal networks and the recycling of nutrients through the soil food web. This is done notably with evergreen plants, but also with the web of insects, worms and microbes, right through to the wider ecology. In the heat, the plants had no time for reclamation. It’s like trying to grab the things that matter most to you in a burning building; inevitably much gets lost.
Certain plants fared better in the heat than others, though trying to find the pattern isn’t always obvious. Walking through my neighbourhood, the trees that have dropped the most leaves are almost all in difficult positions, whether that’s street trees hemmed in with concrete or those in the parks that sit on very compacted or tired soils. The glare of sun bouncing off nearby buildings has also had an impact. In nearly all of these spaces though, it is poor soil that has exacerbated the problem.
Plants adapted to heat, such as Mediterranean types, have shone in good, free-draining soils. But in the wrong soils – those too heavy and rich in nutrients – they have done no better than woodland types, which thrive on our generally cooler, damper summers. In the south, the grasses are bleached summer blond still, but farther north they have mostly returned to more verdant green, as is their way. Grasses are well adapted to seemingly die off only to spring back to life. But wear and tear will start to show, particularly in urban parks, where baked hard soils and burnt grasses are vulnerable to footfall.
The list of plants that have suffered is long, but at the root of the problem is two things: these plants were either in the wrong position or in bad soils. Capitalism has taught us that we can seemingly have whatever we want and so we use plants like paint, as a cheap and easy splash of decoration, while ignoring their actual needs and growing them in places they aren’t suited. Or they have been grown on compacted or thin soils, or soils worn out and hungry from intensive cultivation, endlessly dug and ploughed with little return. Plants grown in these conditions don’t have a thriving soil food community from which they can draw strength.
These ruined and baked soils do not do well in the rain, and if the autumn and winter bring flash floods – which is likely as the other side of the climate chaos coin – the precious top layer will wash away, down drains, into our rivers and out to the sea. This takes all the chemicals we poured on them (that includes our gardens just as much as our farms) into our waters. A bleak outcome.
Our modern lives have swayed us to believe that we thrive only on certainty, but we now have to sit with the uncertainty of the climate crisis. There is no single answer to it, and that is as true for our gardens and parks as it is for our society.
Despite this, some corners thrive. There are gardens that are looking resplendent right now, there are growers gathering in good harvests, there are home gardeners bottling and preserving in great volumes. At the heart of all of these is a love and deep understanding of local soils and ecology – not importing gravel or soils from elsewhere, but growing what suits the situation. Their gardens are thriving because they return their riches back to the only bank that matters: the soil food web.
If you want to weather a (climate) storm, compost like your life depends on it, because a soil rich in organic matter is rich in a multitude of microbial life, and this is its resilience, and a strength it passes on to all of its community.
• Alys Fowler is a gardener and Guardian columnist
