Here are averages that might help you know how often you should change the air filter at home: Vacation home or single occupant and no pets or allergies: every 6-12 months Average suburban home without pets: every 90 days
Rating Newest Oldest. Best Answer: Cut off dead blossoms and dead bloom stalks when the iris has stopped blossoming, but don't cut back the leaves until they begin to turn brown in the fall. The leaves are needed to produce next year's blooms. When you do cut, leave a fan shape about six inches long. Feed your irises a teaspoon of bone meal every fall and when you replant. You can feed again a month before they usually bloom if you like, but they are quite tolerant of just one feeding..
Most rhizomatous iris should be divided every three to five years. If your iris patch is producing very few flowers, it's time to divide and conquer. When transplanting iris, first cut back the leaves to about one third of their height. Lift the entire clump with a spade or digging fork. Use a sharp knife to separate the rhizomes. Dip the knife in ten percent bleach after each cut. The new transplants should have a firm rhizome with roots and a fan of leaves.