The Eden Project is planning to reopen on 17 May 2021, subject to the latest Government guidance. Timed entry tickets for 17 May onwards are available to pre-book online. Our online shop remains open.


Citrus plants growing in Eden's Mediterranean Biome

Monroe tells the fascinating story of how citrus plants can produce some interesting hybrids.

Play video


  • No, the fruits of this tree aren’t lemons on steroids, although they are from the citrus family. In fact, these giants are almost all rind and pith, or 'albedo'.
  • It was possibly the first citrus cultivated in Europe and may have come overland from Persia on the caravan routes. Greek scholar and ‘father of botany’ Theophrastus learned of the citron from the scholars who accompanied Alexander the Great.
  • Jewish mythology identified the citron or ‘etrog’ with the forbidden fruit of Eden and it was believed that eating it when pregnant produced a male child.

Where it grows

The citron possibly originated in north-east India and is now cultivated in subtropical and tropical regions. It needs rainfall of 900–3000mm.

Common uses 

The use of the albedo pith as candied peel is well established in the food industry, but it also produces a soluble fibre for which there is a growing market in the US. The juice of the citron is used as a drink and as syrup.

Useful links