Hi all, and thanks for the replies.

Root damaged is a possibility when they dug out for the new lawn.

No chemicals etc have been used on the "old new" lawn or this new lawn before or after it was laid. But I think the new lawn may have been treated before we received it. But this problem was there before the new grass was laid.

The sand was removed after the latest lawn was laid but the part between the hedge and lawn still has some of the sand under the plum slate.

Can anyone recommend a brand of suitable fertiliser.

Thanks again Gav