One of the main keys to growing vegetables is the use of irrigation or the ability to water your plants as required especially in height of summer. Last season the GardenAdvice team trialled growing vegetables with a drip irrigation system designed to save water and deliver the water directly to the plants resulting in a 30 percent increase in crops.
On an allotment quite often there is not a supply of water for every allotment so you best option is to install an gravity feed with a drip irrigation system controlled by a small battery operated timer.
Using old water system tanks or old farm bio fuel tanks that have been washed out installed on some concrete blocks its possible create a head of water to run a drip irrigation system through a small timer.
The tanks can be filled from a shed or greenhouse roof with a drainage down pipe and topped up with hose from a main allotment watering point of stand pipe in the summer months.