Gardeners can learn about resilient plants and techniques from the city’s design, finds Emma Townshend
Chelsea Flower Show opens to the public today, with the usual floral dresses, celebrity appearances and royal rubber stamping – this year an RHS garden co-designed by the Duchess of Cambridge.
However, Chelsea also increasingly reflects an edgier sense of environmental mission, with charities and organisations taking the opportunity to deliver their eco-friendly messages and advice to a huge nature-loving TV audience, during 12 hours of BBC coverage throughout the week.
The Forestry Commission’s Resilience Garden by Sarah Eberle, for example, aims to highlight the challenge of how to protect our forests in the face of coming climate emergencies. The design features species that will cope with warmer, drier summers and wetter winters, planted around a farmyard grain silo.
There’s also the Manchester Garden, where its choice of planting around an undulating white sculpture, pools of water and hexagonal blocks tells how the city is now Britain’s leader in “future-proofing” urban environments through various schemes.
Readying our cities for climate change
“We are protecting the ecosystems that surround us – for example, rewetting the upland peat bogs between here and Oldham, which can act to absorb sudden rains and prevent urban flooding as well as moorland fire,” says Dr Kathryn Oldham, the city’s chief resilience officer. “Within the city, we have a huge programme for tree planting, as we’re aware that trees can manage temperatures in heatwaves.”
Representing the 10 boroughs of the Greater Manchester area, the design features 10 pollution-tolerant trees, providing shade above attractive, productive and drought-tolerant planting such as thyme and sage. “We want to show how Manchester is trying to protect itself as times change, and how to start a conversation about how others can follow,” says Sam Martin from Exterior Architecture, the garden’s designers.
“Future proofing” a whole city is no easy task, especially when it contains as much heritage as Manchester. The choice of plants is key, Martin says. “To protect the urban environment, we need resilient plants that will look after themselves, that don’t need watering and that can provide for people too.”
Adapting your garden
Chelsea might seem an ironic context in which to put over this sustainable long-term message, given the huge artifice of the pop-up show, which is expected to serve 32,000 pints of Pimm’s over the next five days, and which is built over less than a month and broken down in just five days.
Yet the Manchester team says it provides an ideal platform. “We want the garden to build awareness and start conversations,” Dr Oldham says. So what can ordinary gardeners learn from their showcase? They need a changed palette of plants, for one thing, using species that can adapt to weather extremes and a much greater degree of neglect, especially on less than perfect brownfield sites.
“Our planting needs less watering, has greater tolerance of low soil fertility, and generally, won’t require a great deal of care,” Martin stresses.
His colleague Jonathan Miley adds: “In cities there are often temporary open spaces, for example where a building has been demolished and a new one is waiting to be built. Or in a domestic setting, when a garden has been used as a dumping ground for bricks or building rubble.
“These are perfect spaces for what we call ‘remediation’ – bringing wasted land back into use. One of the best plants for this kind of environment is grasses.” The Manchester garden features Calamagrostis and Deschampsia, two dramatic grasses that fit this bill.
It also means using resources better. For home gardeners, the RHS, which organises Chelsea, recently commissioned useful research on how we can make better use of water.
Scientists from the University of Reading, led by Dr Tijana Blanusa, proved that panicky over-watering during a dry spell is the worst thing to do. Instead, watering container plants little but daily was found to yield excellent results – using that method requires only about a teacup of water per plant.
Affordable home irrigation systems using soak hoses below the surface of the soil worked a treat in the study, with even less hassle. Laid into flowerbeds and covered with soil, they water directly to the roots, so nothing is wasted by evaporation, and should cost under £20 for a 15-metre stretch.
The Manchester garden also demonstrates the benefits of plants being productive as well as decorative. The design includes varieties of sages that can be used in cooking, chives and fennel, and soft thymes edge the paths.
It also includes a good tree for the small garden, the dwarf mountain pine, Pinus mugo, which can be kept even smaller than the name suggests by a kind of bonsai treatment.
Councils can aim to do only so much. But Manchester hopes to involve whole communities. As Dr Oldham puts it: “We’re asking everybody to do their bit. Because every garden counts.”