Is there a species of winter flowering Iris in England?

Question

I saw several Irises flowering this afternoon in the Hill Garden,Hampstead Heath, London

Answer 1

There is a winter-flowering species called Iris unguicularis (Latin for claw, in reference to the roots). This Iris, native to Algeria, has a clump of thin green leaves, and the blue or purple flowers are found within the clump, rather than on tall stems.
In the past, this Iris was known as I. stylosa.
The cultivars 'Mary Barnard' and 'Walter Butt' are improvements on the species.

Answer 2

yes they are