With fall here, the first frost is not far off. Linn County Master Gardener, Claire Smith, describes how to save geraniums before that hits and overwintering mums:
Mums and Geraniums. Two of my favorite flowers. Did you know you can successfully save and replant both from year to year? Mums just speak of fall, of cool crisp evenings, apple cider and hay rack rides. Now available in nearly every fall hue, choosing from sunny yellow to definitely bronze adds vibrancy to a shock of corn stalks and enhances your display of jack-o- lanterns, ghosts and goblins. Mums can be overwintered if you purchase a HARDY or garden variety. If you’re inclined to decorate and discard, choose florist or tender mums. Ask which you are purchasing as they often are sold under the name “mum”.
Garden/hardy variety mums produce underground shoots or stolons which enable mums to survive from year to year. Mums can be successfully planted in the fall if in the ground six weeks prior to the first killing frost. Mums like full sun, but not a night or street light as they are photoperiodic. They require even water, but do not fertilize or cut them back before winter. It’s wise to avoid stress by protecting them from a cold north wind. Wonderful green leaves will provide an accent to your spring blooming plants followed by an explosion of color come fall.
Geraniums have been spectacular all season. Coupled with Dusty Miller and a Kale plant—think silver, pink and purple—the whiskey barrel at the head of my lane provides stunning curb appeal. Because Geraniums can be expensive, overwintering is a good plan for me. And, being a bit on the lazy side, the bag and hang method has worked well. Shortly prior to the first frost, we pull up the plants, shake off excess dirt and hang them upside down inside brown paper bags. In my case, they winter in a closet in an unheated upstairs room. Rooted ends should be placed in water to rehydrate monthly. Prune back and remove all the dead leaves in March, pot up and water well. You’ll be surprised how soon the plants are ready to be transferred outdoors again.While annuals generally bloom longer, any way we can save by overwintering plants year after year is a bonus in time and the pocket book. Just remember to start out with healthy plants from a reputable garden center or horticultural organization.