For generations, one of the most prevalent gardening tricks has been to put shards of broken pottery, or “crocks”, at the bottom of plant pots to improve drainage. This age-old technique has now been debunked by a new study.
In addition to aiding drainage, the shard of pottery would help to prevent the holes at the bottom of a plant pot from clogging up. This is an approved wisdom, and has even been demonstrated on by Gardeners World luminaries, Monty Don and Alan Titchmarsh.
The study, by consumer magazine Which?, suggests this is a myth. Researchers planted 40 pots with the flowering plant “million bells trailing yellow”, a plant prone to root rot in saturated soils, with half receiving crocks and half without.
The plants were recorded for “vigour and flowering impact”, with the final result showing that crocks made no difference to the final result.
Although the crock myth has been discredited, experts believe it is a tradition that will live on despite the scientific evidence.