Tesco has started selling green lemons to help prevent a potential lemon shortage in UK stores.

While the skin of the fruit is green instead of the usual yellow, according to Tesco the fruit is ‘still as crisp and zesty’ as a completely ripe lemon.

The supermarket normally has colour and quality guidelines in place to prevent green lemons making their way into the stores, but has relaxed its specifications.

Poor lemon growing conditions have been reported in Spain, which supplies the UK with the fruit over the spring season. South Africa normally takes over from Spain as UK’s lemon supplier in late June, however, Tesco has decided to purchase lemons from South Africa earlier than usual to avoid gaps in supply.

The move will also help to offset domestic food waste by adding up to an extra two days of shelf life to the fruit as it ripens.

Tesco’s citrus buyer Savia Weidinger-Reich said: “These greener lemons that we now have on sale are already mature and perfect tasting inside but need longer for the skin to turn yellow.

“With the South African crop, that happens towards the end of June as evenings cool, which helps the fruit to colour.

“The move not only means that shoppers will again be easily able to buy a fruit that is growing in popularity, but they will gain extra freshness.”

According to Tesco lemon sales have increased by nearly 10% over the last year.

The green lemons are currently available in 800 Tesco stores across the UK.

It is not the first time the retailer has sold non-spec crops. Last October Tesco offered green satsumas and clementines in a drive to reduce food waste. Both satsumas and clementines initially grow as green fruit and turn orange as nights cool, but the warm weather in Spain prevented the fruits from turning orange.

The retailer says it has committed to making sure no good food goes to waste and works with farmers and suppliers to adjust crop specifications.