Supermarkets are rationing off vegetables as they blame poor growing conditions in southern Europe for a shortage in stores.

Tesco has rationed the number of lettuces each customer can purchase in stores and iceberg, sweet gem and romaine varieties have been taken off sale completely by some online.

An extreme mix of drought followed by flooding and freezing conditions has severely affected growers in southern Spain, while poor conditions have also hit farmers in Italy, Greece and Turkey.

Experts have warned that if the weather does not improve in the coming weeks the problem may continue until April, with customers hit by price rises.

The lettuce shortage follows similar reductions in the supply of courgettes, while salad peppers, broccoli and cabbage supplies are also under pressure.

Concerned healthy eaters have been sharing pictures of bare supermarket shelves with the hashtags #lettucecrisis and #courgettecrisis, while complaining that prices have nearly tripled in recent weeks.

A Tesco spokesman said: “Due to bad weather conditions in Spain, we are experiencing some availability issues, but are working with our suppliers to resolve them as quickly as possible.”