Growing through drought: practical advice for London’s community gardens

It has been a hard summer for London’s community growers. With our fifth heatwave looming this week and regular highs of 30°+; the prolonged dry weather has led to hosepipe bans across the city. We've collated some tips and tricks to help keep gardens healthy through extreme weather conditions, and busted some of the myths around the ban. 

What the hosepipe restrictions mean for growers:

For those unsure about the new restrictions, Thames Water has confirmed several important exemptions.

1. Hosepipes may still be used to water newly planted trees and plants.
2. Commercial businesses growing crops may also continue using hosepipes.
3. Food crops at home or on an allotment when using a watering can isn't practical.
4. Approved drip or trickle irrigation systems are also permitted. These must have a pressure-reducing valve and timer, must not be handheld, and must deliver water directly onto or beneath the soil without causing runoff or spraying water into the air.
5. If you have mobility difficulties, you are permitted to water gardens, plants and allotments and fill or maintain a domestic pond (you don't need the be in possessed of a Blue Badge). 

The hosepipe itself as a water tool is not banned. You may still use one if the water does not come from the mains supply, including:

• Grey water from household sources such as sinks, showers, baths and washing machines.
• Rainwater collected in a water butt.
• Water from a private borehole.

You can use your hose through siphoning, see how here. However, avoid using grey water that contains toxic chemicals, as these can enter waterways at a time when rivers and lakes are already under significant environmental stress. 

Practical measures to mitigate drought conditions:

Short-term tips for this summer

• Water early in the morning or later in the evening to reduce evaporation and allow water to reach plant roots.
• Mulch around plants with compost, bark or other organic matter to keep soils cooler and reduce moisture loss.
• Shade vulnerable crops with netting or shade cloth during the hottest part of the day.
• Where possible, invest in irrigation systems or alternatives such as ollas – porous ceramic pots that slowly release water into the soil.

Longer-term investments

• Reduce areas of bare soil. Covered soil is biologically more active and holds moisture for longer. Soil exposed to sun, wind and heavy rainfall is more vulnerable to erosion and drying out. Let the weeds grow over winter, or plant in green manure crops.
• Plant more drought-tolerant flowering species that also support pollinators and other beneficial insects, including tansy, wild carrot, yarrow, red and white valerian, evening primrose, wild marjoram, viper's bugloss, sedum, hyssop, catmint, ragwort, oxeye daisy, knapweed and rambling roses.
• Grow more perennial crops. Trees, shrubs and perennial herbs are generally more resilient to year-to-year fluctuations in water availability because of their established root systems.
• Harvest water as it moves through your site by using ponds, tanks, swales or marshy areas- if you have the space. Any overflow systems should be designed to cope with increasingly intense rainfall events.
• Install water butts or rain barrels beneath roof downpipes on homes, sheds or greenhouses.
• Consider creating rain gardens to capture and slowly absorb rainfall in times to torrential rain to avoid flooding and soil erosion.

Although drought and extreme heat are placing growing spaces under real pressure, a combination of careful watering, healthier soils and long-term water harvesting can make plots more resilient. Check the latest guidance from your water supplier before using a hosepipe, share these tips with other growers and start with the changes that are most practical for your site.

To hear more about how London’s growers are working with nature to protect their livelihoods and plots from extreme weather, check out our recent piece, “London's driest July in 190 years: how urban growers are coping in extreme heat”.