An annual of disturbed, nutrient-rich ground, especially cultivated land on deep, fertile soils. It is usually casual but can be persistent in S. England and S. Wales. Lowland.
There is a continuous archaeological record of this species in Britain from the Iron Age onwards. Despite this, there were very few records of it in the 1962 Atlas away from its strongholds in the Fens and the London area. Even allowing for the possibility that it had been under-recorded elsewhere, it seems likely that this species has undergone a marked expansion of range since the 1950s. The reasons for this are far from clear.
As an archaeophyte C. ficifolium has a Eurosiberian Temperate distribution.