There are roses and then there are roses. For some reason we group all members of the Rosa family together without distinguishing the vast differences in their flowering, disease resistance, fragrance and overall performance. Fact is, there are a few roses that I have planted and regret doing so. There are many more that I have grown in my garden with delightful results.
There are almost 50,000 rose varieties registered worldwide and several dozen sub categories or species into which each variety falls. It gets complicated.
What to avoid
I speculate that some roses are falling out of favour due to their reputation for black spot, powdery mildew and poor summer flowering performance. My advice is to avoid these varieties. You can do this by taking the time to read the label on the rose bush at the time of purchase. Labels have come a long way in the last few years. Follow these rules for purchasing roses:
If it does not say it, it ain’t so. If the label does not refer to a rose variety as being fragrant, disease resistant or ‘ever blooming’ (code for ‘colour throughout the summer’) than it is not any of these things.
Grown in Canada. Believe it or not, there are roses that are strip mined in Texas and California and shipped up here, usually in cardboard boxes or those ridiculous plastic bags. By this time in June, you might as well forget about these as they cooked in their container a while ago and are dead or near dead. Look instead for roses grown in containers, using a rich loam and labeled ‘Grown in Canada’. You will know that they survived a winter or two in our climate and that they are generally suited to growing in your garden.
AARS – this stands for ‘All America Rose Selection’ and it is a standard bearer of great garden performance. Some of my favourite roses are AARS winners but that is not to say that all AARS are winners in our Canadian gardens.
Plant deeply. A Canadian rose label will tell you to bury the ‘bud union’ (the knuckle where the main plant meets the root). American labels will often tell you to plant with the bud union exposed. Our winters demand that we get that knuckle under some sandy loam.
With several weeks of great rose blooming still ahead of us, now is a great time to plant container grown roses. When you shop for rose bushes this time of year you can often see the actual rose in bloom. There is no question about its’ colour or fragrance.
Note that hot, dry weather in summer generally causes roses to take a rest from their intense late spring flowering period but there is a second wind of flowering that occurs in September through to the hard frost of November.
If winterizing your roses is not on your gardening agenda then I would suggest that you check out the Canadian bred Explorer series of roses. None of these need to be heaped up with soil come late autumn. I like David Thompson best and have a hedge of them in full bloom right now. Avoid ‘Frobisher’ unless you like chasing suckers all around the yard and looking at yellowing leaves most of the summer.
Keep in mind that all roses require at least six hours of sun per day and they enjoy a rich but well drained soil. I add about 1/3 sharp sand to my planting mix.
And this week is the perfect time to purchase and plant Canadian grown, containerized roses.
Mark Cullen is an expert gardener, author and broadcaster. Get his free monthly newsletter at markcullen.com. Look for his new best seller, The New Canadian Garden’ published by Dundurn Press. Follow him on Twitter @MarkCullen4 and Facebook.