Your irises don't look as if they are needing splitting yet to me... You can dig them up and split and it isn't difficult to do just get in there with a large fork once they have finished flowering and lift them. Separate the rhizomes and replant where you want them having cut back the foliage to just a few inches.

Thanks for that, this is an old picture, taken in their second year, so a bit deceiving, they have deteriorated since then, so will follow your advice to split hem. Would it be ok to do that witin the next 2 weeks?

Yes go ahead and split anytime now.

Thanks ...hope it`s dry at the weekend!:-)