A version of this story appears in the February 2017 issue of National Geographic magazine. Citrus, in many ways, stands alone. So many cultivated species have come from so few primary ancestors.

We are used to valorising the mango as our ‘national fruit’ and rightly so ... The mandarin orange is apparently the most ...

The first citrus trees appeared about eight million years ago, before spreading around the world, say international scientists. The trees eventually gave rise to the fruit on our kitchen tables ...

Citrus trees are a long-term investment that will require patience and effort, but the payoff of homegrown fruit will make it ... but any plant in the legume family, including beans and clover ...