Cut Back Knock-Out Roses Next Spring
This year I am doing my column on the Saturday before Thanksgiving instead of after due to the fact November had five Saturdays and only four Thursdays. I can hardly believe it is that time of the year.
We had a pretty good frost so most of the plants have been put to rest for this year. I have to admit we still have not gotten everything put away like we should.
I did have a question from a gardener about her "Knock-out roses." She wanted to know if she should cut them back now even though they were still blooming. You know this the wonderful thing about this very special rose. You do not need to do anything to it until next spring. If there is any winter damage to it, come spring you can cut it clear back without doing any damage to it. They have really been blooming big time this year.
If you have not gotten one of these plants then put it on your list for next year. You will not be sorry. It just keeps on blooming!
You know when it comes to cutting back on plants—if in doubt do not cut them! They are a nice winter interest plus the birds have a little protection. Remember, do not put on your mulch until the ground has frozen. This allows the plants to harden and not be so shocked when the cold weather sets in. Don't forget to ask "Santa" for some of those special garden items you have been wanting. Also, it is not too late to consider planting some shrubs.
GARDEN QUESTIONS FOR CENTRAL ILLINOIS
Q)Is winter protection necessary for roses? A)For our northern states winter protection is a must. But for us in the Midwest the only recommendation is a preventive measure. Summer treatment is the key to winter safety. A rose without plenty of food reserve in its canes, depleted by repeated defoliation from black spot, may die no matter how well protected in the winter. You can lose a few bushes to crowding, too much shade, too deep planting, crown gall and little "critters" but usually not to lack of winter protection. If you feel like protecting your roses a little, it is suggested to mound some soil around the base of your roses. Leaves and peat moss are not recommended for mounding because they retain too much moisture and increases canker disease.
Q)Why do shrubs bloom well some years and others very poorly? This spring my forsythia and flowering crabs were covered with blooms—but the previous year hardly any. A)There are a couple of reasons why your forsythia and flowering crab did not bloom. Some winters are cold enough to kill flower buds of plants such as forsythias. Then, too, many flowering and fruiting ornamentals, such as crab apples, bear alternately, that is they have profuse flowers and fruits one year, but few the next year. There is little the homeowner can do to change this sequence.
Q)How low should fall- planted barberry, spirea, and rose-of Sharon be pruned? A)With the barberry and spirea, cut out at about ground-level, half of the strongest stems; reduce the remaining about half their length. If the rose-of Sharon is on a single stem, it must not be cut to the ground. Cut out some of the branches at a point where they fork, and shorten the remaining ones to one fourth or one third their length.
Q)Can plastic be used as mulch around trees and shrubs? A)Plastic cuts off air and moisture exchange in the soil and virtually drowns the plant. If a plastic material must be used, use the planting mat that allows for air and moisture exchange around the plant. Be sure to not mound the mulch up around the tree trunk. All this does is make a "bed" for creatures to live in while they eat on the tree trunk.
Q)I have heard that I should not mulch my peonies. Is this true? A)Yes. Peonies and bearded iris should not be mulched. Mulch can cause them to rot.
Q)My neighbor says my firewood is full of bugs and I shouldn't store it in the house. What do you recommend? A)He's right! A variety of insects, including woodborers, worker carpenter ants, and wood roaches, live in the dead and dying trees that we use for the fireplace. To avoid problems in the house with these and other insects, do not store your firewood in the basement or any part of the house. When using your fireplace, do not bring firewood into the house that you will not be putting on the fire within an hour. If you wish to leave a stack of firewood next to the fireplace as part of the decor, heat each piece of wood in the oven at 150 degrees F. for 20 minutes to kill any insects present. Firewood should not be sprayed with insecticide, since dangerous fumes may be emitted when the firewood is burned. INDOOR GARDENING: Give Christmas cactus full sun and keep the soil moderately moist. Avoid over-watering houseplants to prevent root rot problems. Fungus gnats around houseplants may indicate the soil is too moist. Place Christmas pepper, cyclamen, kalanchoe and other blooming plants in cool (55-60 degrees F), sunny window for maximum blooming time. Place cacti and other succulents in cool, bright location, and keep dry to encourage flowering in spring and summer. Check all plants for insects and diseases before they are placed near other houseplants.
LAWNS: Avoid walking on frozen grass. This can damage crowns and create unwanted paths.
HERBS: Frequently mist rosemary and keep the soil moist.
If you have any horticulture questions, call the local U of I Extension office Monday through Friday at 345-7034. Volunteer Master Gardeners are not in the office this time of year but they will return your call.
This column is based on information and materials at the University of Illinois Extension office, located at 707 Windsor Road, Suite A., Charleston, 61920; phone 345-7034; or web site: www.extension.uiuc.edu/coles/