Be ruthless. It’s time to chop ornamental grasses and butterfly bushes. Cut them down to the ground.
Also remove the old flower stems and old foliage of sedum to make room for new growth.
In addition, it’s time for serious pruning of lilacs that are over-grown or infested with stems borers. Trim azaleas, rhododendrons, cherry laurels and hollies that make it impossible to look out of the bedroom or living room windows. Some of the branches that you cut can be brought in and forced to flower.
Late winter and early spring are the best times for hard pruning. The roots of all ornamentals growing in your landscape are packed with sugars, carbohydrates and nutrients just waiting to move upward into the stems to produce new branches and leaves. Hardy ornamental plants survive and flourish no matter how drastically you prune them. So you don’t need to fear killing the plant if you remove too much.
Cut those clumps of ornamental grasses as close to the ground as possible. To eliminate the need to carry away the old dry stems, cut them into pieces six inches or smaller and allow them to become mulch. While you are at it, cut those stems of butterfly bushes as close to the ground as possible. I use a chainsaw to prune my butterfly close to the ground, forcing new branches to emerge from the roots. If the forsythia and weigela shrubs are over-grown or not flowering well, cut those branches close to the ground as well. This is how you force the new branches to originate from the roots and not from branch stubs.
Overgrown azaleas, rhododendrons, hollies, yews and cherry laurels should have their branches pruned to 12 to 18 inches lower than the desired height. You will avoid having to prune them again in a few years, and regrowth will have a more desirable appearance.
You don’t have to be a certified professional horticulturist to know how to prune hardy ornamental plants. These plants are survivors and dormant vegetative buds up and down the branches are waiting to burst into active growth. That plant will recover and appear normal in a relatively short time. Trust me.
Plow Pan Is Your Problem
Q We have been growing perennials, a few annuals and various vegetables and herbs on the same large garden plot for about 13 years. I’ve noticed that the plants aren’t as healthy as they once were, despite the fact that we’ve added soil and fertilizer over the years. What do you recommend to improve the soil for the garden overall and in particular where the perennials are located?
–Amanda Gibson, Lothian
A If you have been gardening in the same area for 13 years, and have been tilling or plowing each year, most likely you have developed a plow pan about six inches below the surface of the soil, and it is now affecting drainage and root penetration. The only solution is double digging or sub-soiling. To test my theory, sharpen a broom handle (or use a piece of half-inch pipe) and see how deep you can push it into the ground. Test several areas in your garden. If you can’t penetrate deeper than six inches you have plow pan and need to dig below. If you have a tractor, I have a sub-soiler you can borrow.
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