Managing Last Year’s Mums
For fall flowering, first divide, then prune
If you purchased hardy flowering chrysanthemums for your garden last fall, most likely they have survived the winter, and the clumps are producing multiple stems. What was one plant last fall is now a plant with five to 15 stems originating from the stump. Some varieties of chrysanthemums produce from the root system, while other varieties produce multiple stems from above ground.
Get down on your hands and knees to examine the base of the plant.
In the Garden this Week
If you own property near open water, be on the lookout for mile-a-minute weed. This weed has triangular leaves and sharp spines on the leaf petiole and vine that grab back when you reach down to pull it out. I have found it along the shores of Rockhold Creek, and others have found it along Parker’s Creek. This weed is totally immune to glyphosate (Round-up) and most other weed killers. However it is extremely susceptible to horticulture vinegar. I wish garden centers would carry this product. Perhaps if many request it, they will. In the meantime, horticulture vinegar is available from A. M. Leonard Horticultural Tool and Supply Company, www.amleo.com. Use a pressure sprayer and apply it as a light mist on a sunny day.
Plan A: If you see new stems growing out of the soil, dig up the plant and divide it. It can be divided by using either a small hatchet with a hammer or a large carpenter’s chisel and hammer. Cut the clump in half so you can see the origin of each stem. Select only stems that have roots attached. Place the blade of the hatchet or chisel between the stems and use the hammer to bang the head of the hatchet or chisel.
If the stems are soft, they can be divided using a sharp knife.
Plan B: If the new stems arise above ground, strip the bottoms of the stems of leaves and mound soil over the base of the plants. Better yet, use sharp sand, which filters better around each stem. Distribute two to three inches of soil or sand around all the stems, and keep the mound moist.
The stems will generate sufficient roots to be removed from the mother plant in about two weeks. The plant can then be dug up and shaken loose of soil or sand. Using a sharp knife or pruners, remove the stems and plant them immediately.
Allow the rooted cuttings to become established before cutting them back to within three or four inches of the ground. Do not transplant and cut back the stems on the same day.
Pruning back the top will promote branching, resulting in a fuller plant. I like to shear the plant once or twice before July 21. Stop pruning the plants after July 21 for maximum flower production.