By late spring many of the cranesbills have past their spring best. The leaves are large, soft and tall. Sometimes the whole clump has fallen open.
This is the time to cut the whole clump right to the ground. Its better to do this sooner rather than later while the soil is still cool and moist. The plants will regenerate and flower again in a few weeks. Their foliage will be more compact and harder so able to withstand summer heat. It would be a good thing to give them a feed at the same time to speed up regeneration.