Hybrid Tea Roses
by Cass Turnbull
“They've butchered our roses!” exclaimed the woman on the phone. She was calling to report this crime to PlantAmnesty. “There was nothing wrong with them. The grounds crew just came through and hacked them down to a foot off the ground. My God, there's not a leaf left on them!” As official answer person for the PlantAmnesty hotline and referral service, I did my best to calm her. “Correct rose pruning can look very severe,” I offered, and followed up with some illustrated literature.
It's true. To the novice, the annual pruning of hybrid tea- type roses (the kind most people have) can look quite frightening. Half of the canes are removed at the base and then those that are left get reduced in height to two feet or so. One rosarian I know teaches his students a chant, “You can't kill a rose by pruning it, you can't kill a rose by pruning it.” Novice pruners repeat it to give themselves courage.
Be prepared. Wear tight fitting leather gloves (hard to find, I know). Also wear a long sleeved shirt, not a sweater. Have a sharp pair of by-pass pruners, a lopper and a pruning saw. Gardeners tend to use the new “ARS” type of folding saws. They are easily carried in the back pocket, and fit into tight spaces between canes.
DEADWOOD REMOVAL is first. This means mostly sawing out dead canes and stubs. The stubs, which are many and rather large, can be found close to the graft union (looks like a bulge at the base of the bush).
Take your time and saw each and every dead cane or stub off
carefully and completely.
REMOVE SICK CANES and big old canes. How can you tell if canes are sick? Usually they are the older, thicker canes. But not always. The bark on “unhealthy” canes is mottled and blackish. The perfect, healthy cane (rarely seen in real life) is about as thick around as your thumb and the outer bark is a clear, unblemished green.
SHORTEN UNTHRIFTY CANES. Canes die from the topics down, as a result of freeze or drought. If the cane you are looking at fills an otherwise empty spot, you may want to keep it but shorten it to healthy, or at least healthier, tissue. To find out where that point is, cut a bit off the top and look at the cut end. The pith of an unhealthy cane is black, or partially black and brown. As you continue cutting back the cane, the wood usually becomes a more clear tan color. Then you finish off by cutting to the nearest side branch or bud facing outward.
Prune out canes that are TOO SKINNY, cutting them off where they meet the graft union. One recommendation is to take out canes that are smaller than a pencil.
REMOVE ROOTSTOCK SUCKERS. Cut or tear them off. Many roses are sort of spliced (grafted) to the roots of a tougher plant. The suckers are canes that arise from any portion below the graft union (it looks like a bulge at the base). Suspicious canes have different colored bark, different leaves, and grow in a different form. If the cane originates from the graft union itself, it is probably okay. If the cane originates from the roots, dig down to where it meets the parent root. Twist and pull (yank, actually) it off. If you simply cut a sucker off at ground level, you will get twice as many growing at the same place next year.
REMOVE CANES THAT RUB OR CROSS others and some that fill up the center. The perfect rose bush, should such a thing exist, would have five or six, clear green canes, each as thick as a thumb, radiating evenly from the center.
In reality, one does the best with what is available. Sometimes all the canes are weak and spindly. Sometimes the only decent sized cane that exists goes horribly the wrong way. Sometimes all you have are crusty, mottled, and huge canes. Just do the best you can. Keep in mind, it's no big deal. For all the disease, die-back and death found in roses, they are tough, tough plants. A rose's strategy for survival is to constantly renew itself by sending up replacement canes every year.
Finally, SHORTEN THE CANES WHICH REMAIN. How much? One rule of thumb is to cut no shorter than half a cane's original height. I like to prune most teas to about one to two feet. Some like them shorter, some like them taller. The thinner the cane, the shorter it is pruned. The fatter the cane, the higher you cut.
CUT TO AN OUT FACING BUD, generally speaking. In the late winter/early spring these are easier to spot as they begin to plump up. They are about the size of pencil topics. Some books call them eyes, since they look like eyes. Teeny-weeny eyes. One is apt to find gardeners out in the rose beds this time of year, one hand down, practically standing on their heads, peering at the canes, their faces perilously close to thorns. They are trying to locate the optimum buds. Unerringly, the bud at the right height is in the wrong place, that is - it faces into the center. As you prune, the height of some canes will be a little too high or too low. It's a balancing act. Sometimes the buds are a bit to one side or another. It is even okay to have a few that fill in the inside.
When you cut, the bud just below will be stimulated into growing out. It grows out the same way the bud is facing. You can anticipate how your rose bush will look, by imagining the shoots growing out. If two little shoots grow out from the bud, snap out one with your fingers.
Make the cut at a slant, channeling the growth energy the same way the bud is headed. Don't cut too close, or the bud will die. Don't cut too far away, or it will die back and leave an ugly stub. Actually (should I put it in print?) I find that I tend to cut a bit high on roses. Don't ask me why, except that I know other rose pruners that do so as well. One arborist took me to task for “leaving stubs.” “But it's a rose!” I pleaded my case.
WHY? All this thinning opens up the rose bush, allowing for increased light and air circulation. This is more important on roses than many other plants because they are perpetually plagued by a host of fungal and bacterial diseases. Open pruning helps, but rarely cures. Roses, like cherry trees, are sort of the sick but tough kids of the plant world. The homeowner is well advised to put up with a certain amount of cruddy leaves. And the first criteria for buying a new rose (in our area anyway) is whether or not it shows good disease resistance.
If you find evidence of a nasty bug called a cane borer (little holes) you may care to SEAL THE CUTS. There are commercial products for this, though a dab of clear nail polish or Elmer's glue works well, I am told. By the end of summer your rose bush will be an astounding five feet tall and full again.
Once the rose starts blooming, it is common to “deadhead” throughout the rest of the summer season. This means that every few weeks, you prune off the dead (spent) flowers before they turn into seeds (rose hips). This causes the shrub to continue to produce. (Really — you are preventing the bush from having babies. And so she has to keep putting on that fancy red dress to go out and try again. Poor girl!)
The general rule is to cut to a lower set of leaves with a bud in the axil facing out. We are always told to cut to a set of “five” leaves rather than to the other three leaf kind. The fiver produces flowers, not so the other kind. My husband tested this by pruning one rose bed to “fivers” and the other to “three-ers”. The five leaf bed bloomed more, although the other did still produce flowers.
IN THE FALL
(August or September) many folks let the rose finish up by ceasing to deadhead. The rose sets up hips. The theory is that, by finishing its life cylce, the rose bush will slow down and toughen up (harden-off) for winter. This means that it is less likely to freeze.
Around December, if and when they go dormant, I often shorten the roses some. The excuse I give is to prevent “wind rock” which actually occurs some places. But really, I do it because they are too tall and untidy, flapping around with dead leaves impailed on their thorns.
The major pruning is done in the late winter or early spring (other parts of the country prune in fall or winter). In Seattle's February, most gardeners are in a state of chronic angst, wondering whether or not they should prune the roses. Especially in a warm winter the roses have already started to bud out and grow. I should market Sleep-eze for roses.
The general rule is to wait till GEORGE WASHINGTON'S BIRTHDAY to prune. Our good friend Cisco insists on waiting until March. If one prunes too soon, the plants are stimulated into growing even more. If we have a late freeze, that tender new growth is apt to (shall I say it?) get nipped in the bud. Worse yet, it might freeze to the ground. The temperatures need to get down into the teens and twenties before I worry. If a plant dies, I see it as a wonderful opportunity to go buy a new disease resistant variety.
Now you too can start worrying and watching your roses. You can wait to prune till later, but once the new shoots are expanding, it is difficult to prune without knocking them off. And too, one feels guilty cutting off all that nice new growth. I doubt that it hurts the roses much. After all, you will recall, you can't kill a rose by pruning it.