Soil scientists have urged residents to rethink the use of greywater from their washing machines to water their gardens.

Scientists at Stellenbosch University have published the first ever comprehensive research on the topic in the Journal of Hydrology, and found that especially powdered laundry detergent degrades the soil.

In due course water cannot soak into the soil, as the soil pores get blocked.

The study was led by Dr Ailsa Hardie of the Department of Soil Science in the Faculty of AgriSciences.