Plant mutation without germination

No.11098949 ViewReplyOriginalReport
Is it possible to cause meaningful (non cancerous) changes in plants via radiation (or any other mutagenic substance) when targeting grown individuals, rather than gametes/gametophytes?
For example, if I had an ivy vine, or a strawberry bush with many stolons, or spreading moss, could I induce mutation in the new branches/runners/blades? Or is that unlikely bordering on impossible?