Do you know if they are bearded iris?

Beardeds need to have 6 weeks before the first frost to put down roots. To divide an old tangled clump, dig up the entire mass, dig in some bonemeal or bulb fertilizer, hose the dirt off the mass, toss old withered rhizomes and replant firm ones. If you need to cut a withered portion away from firm, allow the cut to heal overnight in the shade. Cut leaves by 1/2 to keep them from tipping over. Give them a real soaking and ignore for the next month. Then another good soak if you haven't had rain.

You might also want to read through the FAQ here at the forum. How do I dig, divide, and transplant bearded irises?

I would start my having them rake the landscape rock well out of the way, so it won't end up full of soil.

Sue

Thanks for your response. Yes they are bearded iris, they are beautiful and the colors vary. The bed is the whole width of the house. The landscape rock cannot even be seen because of all of the folage.

My grandkids are going to love me, hehehe.