From the Daily Mail in the UK:
Gardeners keen to boost their crop of tomatoes may be surprised to learn they can turn to an unusual and free source of fertiliser.
Allotment growers can enrich the soil and therefore their plants using their own wee, according to a new study.
Scientists discovered the unusual addition made crops up to four times larger.
A team of Finnish researchers found that sprinkling tomatoes with human urine mixed with wood ash was the ultimate eco-friendly fertiliser.
It worked just as well with cucumber, corn, cabbage and other crops.
Although scientists have previously tested urine on plants, this is the first one to mix it with wood ash.
The mixture produced bumper harvests when compared to untreated plants.
It could one day be substituted for costly synthetic fertilisers.
The university study, published in this month's Journal of Agriculture and Food Chemistry, found using nitrogen-rich urine does not carry any risk of disease.
When combined with wood ash is perfect to provide minerals and reduce the acidity of soil.
Report author Surenda Pradhen said the findings could lead to a new source of cheap fertiliser without the need to use potentially dangerous chemicals.
'The results suggest that urine with or without wood ash can be used as a substitute for mineral fertiliser to increase the yields of tomato without posing any microbial or chemical risks,' she concluded.
Read more: http://www.dailymail.co.uk/sciencetech/article-1214346/Urinating-tomato-plants-fruit-times-larger.html