Wee tip for compost that every gardener should know about

And one of the city's top growers is sharing the secret of his success to encourage others to adopt his slightly unconventional fertilising method - adding urine to compost.

Peter Wright MBE collects around six litres in recycled milk bottles every week, which he then adds to the compost bins in his back garden or to the large compost heap at his Edinburgh allotment. The acting chairman of the Federation of Edinburgh and District Allotments and Gardens Associations (FEDAGA) said the old technique provided a number of benefits, with urine being long-established as a free compost "activator".

Mr Wright, 70, who lives in Mayfield, said: "It helps as an activator. It attracts bacteria which activates the compost and gets it working. It is the bacteria that decomposes the food and peelings on the compost, and then the worms get to work on it.

"The urine is putting goodness into the compost as well - you get all the trace elements."

He added: "Energy is also saved. The water used to flush your toilet is treated to drinking water quality, using energy not only to purify, but also to pump it to your house.

"The waste water has to be treated at the sewerage works before being put back into rivers or the sea, again saving energy."

Mr Wright, a grandfather-of-three, has been growing potatoes, onions, sweet peas, red cabbage, white cabbage and beans at his allotment on Lady Road since 2003 with his special compost.

He said: "My uncle was a farmer and he used to do it. My aunt used to pee in a bowl for the compost. My other aunt and uncle fed tomatoes in their greenhouse with pee.

"You're just putting back into the land what you took from it. It's been a well-known practice for centuries."

Mr Wright was honoured with an MBE in 1993, while working in China, for his services to export and the nuclear construction industry.

He worked as a consortium site manager in charge of the construction of a power station in the Philippines before retiring in 1998.

Mr Wright, who recycles household waste in three compost bins in his back garden, admitted that family and friends think he is "slightly eccentric".

"Everybody thinks I'm a bit mad," said Mr Wright, who urged other keen gardeners to follow his lead.

He said: "If everybody in Scotland saved their pee like that, we'd probably be energy neutral!"