Extremes of weather from heavy flooding to long periods of drought, that are only set to worsen with climate change, present an ever-growing challenge. However, creating rain gardens can help to reduce the risk of flooding whilst coping with dry spells too. Despite its name, a rain garden is not to be confused with ponds or bog gardens, which are designed to retain water permanently. Instead a rain garden only remains waterlogged during periods of rain and then for up to two days afterwards, following which it can be dry for long spells. With such extremes, plants are carefully chosen that will thrive in these conditions.
When it rains, run-off from roads, pavements, driveways, patios and rooftops all contribute to an increased risk of flooding as drains become unable to cope with the sheer volume of water. Moreover, rain water that does find its way into public drains will, in turn, end up in streams and rivers, the nutrients and chemicals polluting the water courses and harming wildlife. Creating a rain garden not only diverts some of this run-off away from the drains but also acts as a filter whereby a high percentage of the nutrients and chemicals are removed.
Rain gardens are low maintenance, so they can almost be left to look after themselves. In times of drought rain gardens do not need watering, conserving not only natural resources but time too. (However, they will need watering in the first couple of years whilst the plants become established.) As the plants grow and provide ground cover, they act as a natural weed suppressant. Minimal intervention also benefits wildlife as the site can be left fairly undisturbed apart from occasional tidying and pruning. Rain gardens are also more effective than lawns in soaking up rainwater. An important consideration is where to site the rain garden with various factors to take into account. These include capturing surface run-off from roofs and other hard surfaces, channelling the water into the rain garden, the minimum distance required from buildings and the maximum slope of the garden area. Whilst the rain garden will soak up plenty of water, the ground may nevertheless still become waterlogged and unable to contain all the precipitation. In these instances, any excess water should be able to divert to a drain to avoid flooding the rest of the area.
When designing the rain garden, it’s useful to sketch out a plan of the site. Whether it’s a small-scale rain garden in a container or a much larger area of garden, decide on the size and shape and create a planting scheme to complement or contrast with the rest of the surroundings, ensuring that plants that cope with waterlogging are placed towards the middle and those that also like dry conditions positioned around the edges.
Spring and autumn are the ideal times to start planting a rain garden. When selecting plants, consider their height and spread as well as colour, texture and structure so there is plenty of variety. Think how the garden will look during the different seasons too. Statement planting can bring bursts of colour whilst grasses add year round structure. Choose native varieties that will attract pollinators and increase biodiversity. If you’re not sure what to plant then the Royal Horticultural Society (RHS) has some suggestions.
 To make even more of your garden, why not install a garden bench, somewhere to sit and enjoy watching the wildlife. A bench or chair handmade by TDP from recycled plastic waste is the obvious choice as, just like the rain garden, the award winning sustainable furniture is suited to both extreme wet and dry conditions – the recycled plastic profiles from which the furniture is made are guaranteed to neither rot nor split, so will look just as good, year after year, as the day the furniture was installed. Rain gardens offer not only a practical way of diverting rainwater away from hard surfaces and storm drains, but offer a creative way of solving some of the challenges that climate change brings. Even just one rain garden can make a difference and if everyone created one, the effects could benefit communities across the country whilst helping to reduce the effects of flooding.