Editor's note: This column will be on hiatus for several months.
We planted mums nine years ago that return with blooms and lovely fragrance every fall. But they have grown long, long "legs" and sprawl. What's the solution? Should they be divided?
Too much nitrogen fertilizer contributes to legginess, as does overcrowding. Most mums need to be divided as often as every two years to keep them vigorous. Yes, you can do that in spring. Discard the center of the old clump. Divide and transplant the rest. Chrysanthemums need full to part sun. If shade has increased, that's another reason to transplant to a sunnier location.
To make mums compact, tip prune. You can start "pinching" off the ends of growing tips when plants reach about 6 inches high in spring. Repeat about every two to three weeks. Experiment to see what interval works best for your mum variety. After the last pruning, it takes time for mums to produce buds, so stop pinching several weeks before you expect blooms.
My Egyptian walking onions grew back too close together. Right now there are green shoots about 6 inches high coming out of the ground, one almost on top of another There is no way the bulbs won't be stunted. Can I move them to respace them?
Egyptian walking onions are one of those crops that, once you plant them, can go on forever. When the onion stalk leans over and its head of bulblets takes root in the soil, new plants will be very close together. You can leave the entire clump to sprout into young plants and harvest them like spring scallions. Alternatively, now is a good time for you to separate and respace bulblets, which insures the individuals grow into large mature plants and perpetuate your crop.
University of Maryland Extension's Home and Garden Information Center offers free gardening and pest information at extension.umd.edu/hgic. Click "Ask Maryland's Gardening Experts" to send questions and photos.
Digging deeper
Seedbox, rattlebox
Ludwigia alternifolia
During autumn foliage displays, keep a close eye out for other plant shows in progress. Seedbox wildflower is one. All growing season, it has displayed one charm after another. First, weeks of little flowers with yellow petals framed by a square of sepals, plus red stems and highlights, followed by red autumn leaves. And now, little brown boxes. These cubical seed capsules persist for some time, providing winter garden interest and wildlife food. A shake of the capsules produces a rattle, inspiring its other common name, rattlebox. Seedbox is a Maryland native perennial growing to 3 feet or more with a upright profile, which can be massed to make a statement. It enjoys damp soils along waterways, marshes, rain gardens or that wet spot in your yard. Give them full sun to part shade. They are trouble-free.