QUESTION: "We have a new home (2 years old) and I have Knockout roses across the front of the house. Some have grown quite bushy and, not being a gardener, I am uncertain when or if I should prune them. If so, do I prune at a slant or what? They have been absolutely beautiful. Also, I have not "deadheaded" them but wonder if I should. Thanks for any advice you can give me." - Beth Haynie
ANSWER: First of all, it is not necessary to prune roses at a slant. Pruning comes down to a matter of personal taste and what you find aesthetically pleasing to look at. If you feel you need more uniformity and want them all about the same then you may need to prune. If you prefer a wilder, more natural look, some slight trimming could be all you need to do.
Deadheading refers to pinching off spent flowers to force the growth of new blooms. The deadheading process fools the plant into believing that its reproductive cycle is not yet complete, so it compensates by producing additional blooms and thus the seeds that accompany them.
The Knockout rose was introduced in 2000 and became an immediate favorite due to its hardiness (in USDA zones 4 - 9) and its exceptional disease resistance, blooming from spring to frost. The Rainbow Knockout is one of my favorite varieties.
QUESTION: "I am not able to work in my yard during the hot weather so therefore my yard is a MESS! Weeds, I know, can be cut down anytime and I have a ton of them. But I have Rose of Sharon to be cut and other bushes (I am not quite sure of their names) that need to be trimmed. So is spring or fall the best time to do this?" - Linda Sutterfield
ANSWER: Fall is here and what a time to be outside! Weeds can usually wait, but when they put on flowers, they should be clipped or pulled off as soon as possible because they will produce seed and spread all over for germination next year.
If you aren't sure what the shrub varieties are, the rule on spring and summer flowering shrubs is to prune them after their blooming cycle. Generally, spring and early summer flowering shrubs will set their buds for next season by mid summer. If you prune those during fall/winter, you will lose flowering for the following year. Rose of Sharon will bloom throughout the summer season and blooms best on new wood, so you can prune it at any time.
QUESTION: "I'm trying to develop a sloping southeast facing rock garden in a full sun area. The soil drains well because of the slope. It is about a 45 degree angle. It is anchored by rocks with planting spaces in between.
I formerly had St. John's Wort and coneflowers growing in this area. While they seemed to grow well and seemed to be shunned by deer, still I wasn't satisfied because neither spread. The St. John's Wort did not make a significant enough statement with either the tiny blooms or with the less than luxuriant foliage. The coneflowers may have been the wrong sort as they had small blooms with small rounded cones and didn't show up well.
What I think I need is a ground cover to start over with. Do you have any recommendations for this sunny, deer-prone, sloping rock garden as to groundcover to spread among the rocks on the full sun slope?" - E. Clark Buchi
ANSWER: you could go with any number of ground covers but the ones that I would choose for the area would be Dragon Red sedum, Vinca or Periwinkle and Green Sheen pachysandra. Spread them out across the area and they will eventually come together. You could also mix in some creeping thyme which we have amongst our plantings around rocks and such. You might want to add some of the low growing ornamental grasses for texture, easy maintenance, and winter interest.
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