Easy to Grow Shrub Roses!
Each week, I receive emails asking how to care for their shrub roses. Shrub roses, which include the Knockout Varieties, are great to work with. They require little effort and hardly any ongoing attention and yet, they bloom gorgeous blooms from April (in many zones) until hit by a hard frost in fall. For the color and life they add to gardens and landscapes for such an extended period, they offer one of the best values around.
Shrub roses, like regular roses, do enjoy a pH of around 6.0 to 7.0. Most much all rose varieties require about 6 hours of sunlight each day, which is preferably morning sunlight. Protection from the hot afternoon summer sun will help to keep them happier. It is a good idea to watch the sunlight in the area you want to plant shrub roses to make certain that there is not only enough light, but afternoon protection.
They grow best in areas with high organic matter content, so you can’t go wrong by mixing in aged manure and/or aged compost into the soil. When planting shrub roses, dig holes 18 to 24 inches deep, place the plant’s root system (minus pot if container grown or minus plastic if bare root), fill in hole with a blending of the soil and organic matter up to the root collar. Then, mound around the base of the plant with aged manure, aged compost, or wood bark mulch. Be sure to add more organic matter or mulch each spring. Water the plants at least once a week during the growing season. Do not water roses by overhead irrigation or other type of sprinkler system. Morning watering is best for shrub roses as it will allow time for the sun to dry any moisture on the leaves.
Organic matter is the best to give the plants the nutrients that they need, but supplement fertilize (if you use it) should be applied in early spring after the shrubs have begun leafing out.
Pruning is a big topic, so let’s address that now. Early spring, before the shrubs begin to leaf out, prune out all dead, broken, damaged, touching, or crossing branches. Once accomplished, the plants can be clipped for shape, which is a personal issue as some like the natural look while others prefer a rounded manicured look.
A couple of common problems of roses to look for are cane borers and canker.
Cane borers are the larvae of Sawflies and Carpenter Bees. They lay their eggs on the tips of newly pruned stems in late spring. The eggs hatch and eat their way through the stems towards the center of the plant. If they reach the center of the plant, it can kill it. If you notice a small hole in the center of a pruned cane, it is a sign that the plant may contain borers. Brown sections on the stems/canes, dying foliage at the top of plant, wilting and yellowing leaves that drop off also can indicate borers. Treatment of borers is simply to prune the cane just below the infected area until you see solid greenish white in the center of the cane.
Rose cane canker is a fungus that spreads down the canes and will can cause girdling of the plant and/or lead up to the death of the plant. I have a link to the University of Illinois Extension site with a report on rose cankers complete with pictures for diagnosing.
http://web.aces.uiuc.edu/vista/pdf_pubs/626.pdf
These are common issues with shrub and other hybrid roses that one should be aware of. I hope you have found it helpful.
Until next time……Cheryl
To respond to or suggest topics you would enjoy reading about, drop me an email at cherylsnotes@greenwoodnursery.com .
