If you're a gardener, you know you need to prune. It is essential for healthy plant growth and yard maintenance. It can also be the single worst thing you ever do to your plants, aside from forgetting to water them, if you're not careful. Here are some harmful pruning habits to avoid so that you can keep your gardens growing in the right direction.
1. Pruning at the Wrong Time
I am guilty of going after my garden with loppers whenever the mood strikes me, which has resulted in some disastrous side effects over the years. I ultimately made myself a pruning calendar, because one of the biggest common pruning mistakes gardeners make is pruning at the wrong time. The right time is largely dependent on the plant and the type of pruning you need to do, but in general, there are a few basic rules you can follow.
Winter is the best time to prune most tree species, especially those prone to pests. Pruning opens up your tree to infections from diseases and pests, and since cold weather eliminates most of those, it makes sense to prune during this time. For deciduous trees, winter give you another advantage—sight. You can see the shape of your tree better without the leaves, allowing you to make more informed pruning decisions.
Early Spring Pruning
A lot of pruning takes place in early spring, which is actually perfect because it gives gardeners something to do while things are still too cold and muddy to plant. This is the time to get out your loppers and shears and cut back your ornamental grasses and herbs. It is also the time to take four inches or so off of your semi-woody perennials, like butterfly bushes and Russian sage, to encourage strong stems and vibrant blooms. You could also trim these woodier plants during the winter, but that takes some of the thrill of spring cleaning out of it.
Evergreen shrubs like boxwood might still be green in early spring, but this is the best time of year to prune back any foliage damaged during the winter. However, hold off on doing a lot of shaping until a little later so that new growth will cover up the cut tips quickly.
Wondering when to prune your roses? Along with any summer flowering trees, shrubs, hydrangeas, and vines, spring is the best time to cut back your rose garden. Use this time to remove dead or damaged growth and to do any shaping or size reduction.
Early Summer Pruning
Let’s get back to those evergreen shrubs. Now that you have removed the damaged growth, this is the time to shape and hedge your evergreens. As you trim, however, don’t forget to do some interior thinning to encourage healthy growth and discourage pests.
Spring flowering shrubs like lilacs, forsythia, and rhododendron form buds for the following year after their spring flowering, which means that you need to get out there and do your pruning before they form, or else you will end up cutting off those flower buds and sabotaging next year’s growth.
Fall is the time of year when I am most tempted to hack away at old growth, but I am learning patience. Fall is a good time to deadhead any annual and perennial flowers that will give you another flowering before the frost. Once the frost has passed, you can come back in and cut back any flowers that are not needed for reseeding. Don’t forget to mulch your beds, too, to protect them from frost heaves.
2. Tree Topping
Have a tree in your yard that is getting too tall? Convenient as chopping off the top might sound, experts say that tree topping is a harmful pruning practice. Instead of limiting growth, it actually creates unattractive, broom-like growth that is more prone to breakage. On top of that, pruning wounds created by topping take longer to heal, opening your trees up to pests and diseases, and the increased sun exposure also leads to bark damage.
The best way to avoid the need for tree topping is to plant trees in locations suitable for their size and to consult with a professional arborist about alternative pruning strategies for large varieties.
Ever heard the expression "death by a thousand cuts?" Tipping, or stubbing out, is a bit like that. It might seem like these small cuts hurt the plant less than a few big cuts, but it actually promotes much more growth than is healthy.
Every time you snip the tip of a branch, four to six new branches sprout. As those grow, we snip again, and the process turns into a vicious cycle. You are much better off making a few, large, selective cuts at the appropriate time.
4. Conifer Stubs
Conifers grow quickly, and those long limbs can get in the way of windows, walkways, and views. My first instinct is to just cut the branch off at the problem point, but like most of my pruning instincts, this is a recipe for stub trouble. Trimming a conifer branch like this leads to a permanent, brown, ugly stub that will never go away. To avoid this, cut the offending branch back to the trunk or the nearest healthy lateral branch.
5. Skipping Pruning
Pruning can feel like a hassle, but skipping out on pruning entirely leads to less productive, fragile plants. You will lose out on blooms, color, and garden space, so face your fear this year and get out there and prune right!