Repsol YPF

Sixty per cent of the world’s population will experience water shortages in less than fifteen years’ time and two out of every three citizens will have problems accessing water, according to data supplied by the UN. In addition to the gradual increase in temperatures, the lack of rain, and the pollution, an incorrect use of water is one of the main issues of this global problem, according to the World Water Forum. Large amounts of water are wasted that could be reused, in the garden, for example. 

Greywater; a good fertiliser

If you thought that the water used for cooking, washing, in the bathroom or the sink was no good for anything, you are wrong. This water, also known as greywater, which may seem useless at a first glance, can become the perfect fertiliser and is highly valuable for horticultural tasks. 

Although greywater pollutes lakes and rivers due to the amount of phosphorus, potassium and nitrogen that it contains, its excellent nutrients can, however, be used to water plants, once it is treated. As such, for example, gardening filters retain the cooking oil and direct the pre-treated water towards impermeable flower beds containing marsh plants which purify the water, making it possible to recover up to 70 per cent. 

Another system for recovering greywater is to use mulch. As the charity Ecologists in Action reports, this involves directing the greywater towards ditches filled with a layer of tree bark, straw and leaves, which will serve as a treatment.

Furthermore, the water from an aquarium or fishbowl, from vases or that which has previously been used to cook pulses does not need to be treated in order to be used for watering. Quite the opposite; this is water that can boost growth in your garden, since it contains a large amount of vitamins and mineral salts. 

Put rainwater to good use

Another interesting way of saving water in gardening tasks, and not having to use tap water involves collecting rain water. A simple way of storing this water, which is perfectly usable for watering, involves installing a recipient underneath any downpipe on the house. You can store it in drums or any other large recipient, although you should not keep it for too long without using it. 

Other complementary measures

As well as reusing water as stated above, you should consider certain habits when looking after the garden which will enable you to save water. As such, it is sensible to water during the night; it is not so hot and the plants will make better use of the water. Furthermore, and especially during the summer months, place plant pots in shady areas, so that the plants need less liquid to survive. 
You can also make holes around the trees so as to make better use of rainwater or watering. In terms of plant types, it is recommendable to use local species because they will be used to the regional climate. You will not need to water them as frequently so that they grow properly.

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