Why 18-inches? Well, that’s what works best for my shrub roses. Clearly, they need to be cut back or they become unmanageable (fine for large commercial sites, not so fine for a small residential lot), but what height? I’ve tried 12-inches. I’ve tried 24-inches. The first was truly too much. The plants struggled that year. At 24-inches, you could really see where the plants had been cut off and the new growth stood out in an odd way. At 18-inches you can clear out the riff-raff (dead parts), direct structural growth and still leave enough resources for the plants to grow to 5½ to 6 feet tall during the summer. That’s just right in my opinion.
What things do you need to consider after height has been established? Well, cleaning out dead or diseased branches is important. Then, I select for (keep) branches that are headed up and out—not going into the canopy of the plant or growing too close to each other, causing damage. Making sure there is good air flow will help reduce disease (though I see very little disease in my 'Double Pink' Knockout Roses). After those choices are made, I cut next to a bud that points outward, helping to direct future growth. That’s it! I spin around my shrubs with my 18-inch stick and make decisions about where to cut. I’m not saying it’s the fastest process ever, but it’s not all that slow and I really enjoy the work. In the end, I’m almost always pleased with how the pruning went and am rewarded with bountiful blooms all season long—no other management required.
What’s on your garden tending list this year?