There are many benefits to collecting rainwater, something that homeowners and businesses are finding out. With changes in our climate expected to make our weather hotter and for longer periods, it could be that we face more summer droughts and water shortages.
For those of us enjoying part of full-self-sufficiency with our garden or allotment, being short of water is bad news for our crops. It makes sense, therefore, that many gardeners are investing in rainwater collection and polytunnel irrigation systems. But rainwater is not just for plants…
Collecting and using rainwater
There are two rainwater harvesting solutions broadly categorised as potable and non-potable.
- Potable solutions – using a variety of filtering systems, rainwater is turned into water that is safe to drink and shower.
- Non-potable – is probably the solution we are all most familiar with. Rainwater is collected and used as garden irrigation systems but is also clean enough for flushing toilets and washing down cars, buildings, windows and so on.
What you want to use the recycled rainwater for will inform which harvesting system is right for you. Clearly, water that you want to drink and cook with needs to be safe to do so. If this is your aim, consider working with a professional rainwater harvesting specialist.
Why collect rainwater?
From water butts to reed bed filtration systems, collecting rainwater is simple but brings many benefits;
1) Conserve water.
As an alternative water source for watering the garden or for use with polytunnel irrigation systems, collecting rainwater makes perfect sense. During the hot dry months of summer, you will have plenty of water to keep your cropping and fruiting plants in great shape.
2) Conserve energy.
When you turn the tap on, you use water that is chemically processed at a waterworks. This takes energy and so, by consuming less tap water you are consuming less energy too.
3) Prevents flooding and erosion.
When it rains, the majority of the water if funnelled away in sewers and storm drains. This hard landscaping prevents rainwater from seeping naturally into the water table below. Slow runoff or blocked drains lead to localised flooding and erosion.
4) Decrease water contamination.
Farmers and commercial food growers in an attempt to satisfy demand will often turn to chemical insecticides and pesticides. When it rains, this runs off into watercourses and can cause contamination. Limiting runoff means reducing contamination in lakes, stream and rivers.
5) Reduce your water bill.
For those on a water metre, washing the car with harvested rainwater and watering the garden with rainwater means you pay less for water.
6) Supply plants with ready nutrients.
Rain contains nitrates, an important nutrient for plants. It becomes available to plants as nitrogen, one of the three key macro-nutrients that your plants and crops need to thrive. Nitrogen is the nutrient that gives the plants it lush green, abundant leaves. Many forms of nitrogen are not absorbable by plants and so sometimes, those expensive fertilisers don’t provide everything your plants need.
7) Provides ‘soft’ water.
Depending on the rock or watercourse that rainwater filters through gives soft or hard water and varies across the country. Hard water contains dissolved calcium ions and magnesium ions, making it hard for detergent and soap to frith and clean items. Soft water is the opposite and so using potable rainwater to wash clothes etc. gives a better clean. And neither is there a lot of soap scum to deal with.
Harvesting potable water
Potable water is achievable by creating a system that filters it. There are many ways of doing this, some of which are in action in countries where sourcing water from wells and other natural sources is the main source of drinking and washing water. You can create your own potable water system.
Harvesting non-potable water
The simplest way is to invest in a water butt, connect it to a drain pipe and collect water each time it rains. Using a watering can, you simply water your plants and flowers with it.
It is possible to refine the process, creating ‘pressure’ in the system to use it as part of an irrigation system, perfect for no-fuss water of flower border, allotments and polytunnels too.
Do you use rainwater in your garden? Have you noticed a difference in your plants?
Originally posted 2018-04-03 09:00:18.
Sean Barker is the MD of First Tunnels, and is enthusiastic about providing quality gardening supplies to gardeners across the UK