My French granny says it is more hygienic to poo in a big hole in the garden, like she did when she was growing up, than it is to go inside. Is this true? She also said that in olden days, people collected pee and used it to make plants grow better. Could we do this now?
• It was urine, not excrement, that was collected in barrels in 18th-century London and shipped to the alum industry in Whitby (24 February). The excrement, or night soil, was collected separately and sold to market gardens in east London and Essex.
Derek Morris, Harpenden, Hertfordshire, UK
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• The nitrogen in urine is a useful horticultural nutrient, but urine shouldn’t be put directly onto plants because the concentration of nitrogen it contains could cause chemical scorching. The best use for it is in your compost heap.
UK readers who listen to BBC Radio 4’s Gardeners’ Question Time will be familiar with one of the programme’s panellists, an organic gardener who advocates urinating directly into your compost heap whenever you happen to be working in the garden.
This might be easy enough for men, depending on how many neighbours can see over your garden fence – but I find one of the otherwise much-maligned plastic food containers to be useful for transporting urine from the bathroom to the garden.
Pam Lunn, Kenilworth, Warwickshire, UK
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