Watercress was grown along the Wandle from about 1850. The cress bed would be flooded raising the water level by 4ins(20cm).This would protect the plants from frost, and encourage early growth. Watercress was one of the few salad stuffs that could be bought for most of the year. The number of cress beds increased greatly until the 1930's. Then in 1937 there was an outbreak of typhoid in Croydon, and the cress beds were blamed. In fact a polluted well in Addington was the cause but by then the damage had been done. It had become more profitable to use the land for building. Added to that a wider variety of fresh vegetables were becoming available, so the market for cress declined.
Mr Wakefield remembers watercress beds by the Merton Boards Mills and by Shirley's mill, they were there:
"cause the Wandle used to be all winding in and out round there".
Peppermint(Mentha Piperita) has been grown in Mitcham since before 1750. The soil in Mitcham has a special quality which meant that the plants grown in Mitcham also had a special quality. The oil produced from these plants was the best in the world. Even when the plants were transplanted to other countries the quality of the oil produced did not compare with that distilled from the Mitcham plants.
Perhaps one of the oddest crops grown in Mitcham was the squirting cucumber, (Momordica Elaterium). The plant gets it name from its habit of squirting its seeds and some of its juice when it is ripe. It was said to be quite dangerous to walk among the ripe fruits as the juice could cause painful irritation to the eyes. The fruit was collected and the Apothecaries Company made it into elaterium, a purgative.