#46 Early Spring Rose Care and Pruning

It’s been nearly a year since I’ve written my column for The Smithville Times.  In the interim I’ve been very involved with that newborn granddaughter I mentioned  in February ’08 (she just had her first birthday), and with the election of last year.  Finally, I’m ready to return my thoughts to the garden.

It was rose pruning time when I last wrote, and so it is again.  I’m beginning the process a week or two early, since I have about 70 bushes to prune.  If you have only a few, you can start anytime around Valentine’s Day, or a bit earlier.  You don’t want to prune roses too early, or you’ll force a lot of tender new growth that might be killed in a hard freeze.  If you wait too long and the roses have budded out and begun to grow again, you may be wasting the plants energy by cutting off that very new growth to get the bush size or shape you want.

Some rose growers, especially those growing the modern Hybrid Teas and for rose shows, make a science out of rose pruning.  They cut the plants back very hard, to 18” or so, forcing them to branch out and produce only a few very large flowers in time for the exhibition.  If you are growing for the garden, or for an abundance of bloom, you can prune much less harshly.

I grow mostly Old Roses, and my collection is mainly the old Tea Roses. I start by cutting out any dead wood, and then cut them back at most 1/3 in height.  If there are branches that are crossed and rubbing, I chose the less healthy one and cut it out.  I do make a point of cutting the roses back to an outward pointing bud eye, which encourages them to spread out, rather than become denser in the middle.  Having that more open center allows more air to circulate, and discourages fungal diseases like black spot and powdery mildew.  Lastly, when the bushes are 3 or years more in age, I take out the oldest, largest cane to the ground.  Roses bloom on 1st and 2nd year growth.  This will help you control ultimate size and renew the bush a bit each year.

Growing the old roses, and some of the modern varieties hybridized for disease resistance, will make a big difference in general health of the plants and diminish their need for intensive maintenance.    One source for a list of resistant roses is www.earthkindroses.tamu.edu/EKroses.html .  These Earthkind Roses are a promotion of the Texas Aggie Horticultural Extension service, and specific to our TX climate.  Don’t think you must be limited to these few; it has to do with the class of roses they come from.  You can choose from any in the Tea or China class, some of the old Polyanthas, and then the old newer Shrub roses specifically listed as resistant to foliar disease.

Another trick I’ve learned over the years, living in warm winter areas like TX and CA, is to spray the bushes with dormant oil spray a few weeks before the pruning season.  I use the full dormant strength spray of 5.5 oz to each gallon of water.  The spray is organic; it is simply a refined oil based product that works by encasing and smothering overwintering pests and diseases on the leaves and canes.  It has gotten expensive and so this year I did a little research and discovered that you can use vegetable oil as a substitute.  I use my hose end sprayer (my Milnour brand has served me well for more than 15 years), pour in the canola oil, and then add about ½ tsp of dish soap to 16 oz of oil as a spreader/sticker.  I was able to buy a gallon of canola oil for about $7.50 at HEB.  The labeled horticultural oil was as much as $8 a quart at Kimas and Lowe’s Garden Center.  The other advantage of this dormant spray is that it causes the roses to drop their leaves.  In our climate the bushes never go really dormant.  The leaves hang on, make it hard to see plant structure when pruning, and then look shabby (until they finally drop off) when the new foliage emerges.  The spray takes care of that problem, in addition to its pest prevention properties.