Prepare Your 7 Selected Plants for Autumn Harvest by Pruning in August, Yielding an Additional Blossom Spurt Before Summer's End
August is a crucial month for garden maintenance, as it's time to prune and shape various plants to prepare them for the rest of the year. Here's a comprehensive guide to help you navigate your pruning tasks.
Wisteria plants benefit from a two-step pruning process. After flowering in the summer, prune the long, whippy green shoots to about 5 leaves (around 15-30 cm). This controls size and encourages flower bud production for next year. This summer prune complements a winter prune in January or February when stems are shortened to about 2-3 buds.
Perennials can be lightly pruned or deadheaded in August to refresh plants and improve their appearance. Some perennials, such as yarrow, bellflower, asters, lavender, hardy geranium, lady's mantle, bearded iris, and bee balm, can also have heavier cuts to promote fall blooms or control their size.
However, there are some plants that should not be pruned in summer to protect flower buds and prevent vulnerable new growth. These include plums and cherries, which can promote silver leaf disease if pruned in winter. Hydrangeas that bloom on old wood, such as Bigleaf hydrangeas, should also be pruned in late winter or early spring.
Most trees and shrubs should avoid heavy pruning in late summer, as it can stimulate new growth vulnerable to cold damage. Light trimming and removal of diseased or dead wood is generally acceptable.
Shrub and climbing roses can be lightly pruned in August to remove dead or diseased wood and shape plants. However, heavy pruning is best done in late winter or early spring. Rambling roses do not repeat flower after blooming in summer and should be pruned in summer as the season ends.
When pruning, protect your hands from thorny roses by wearing garden gloves. A pair of pruners can be purchased from Amazon for all your trimming needs, and a quick haircut with a hedge trimmer can be done on shrubs with affordable options available under $100 from Home Depot.
In colder climates with fall frosts, do not prune shrub or climbing roses this late in the year, as it may stimulate growth that will be damaged by frosts and freezes. Similarly, Oakleaf and Bigleaf Hydrangeas should not be pruned in summer. Especially Bigleaf hydrangeas bloom on old wood, so pruning in summer would remove flower buds.
Bougainvillea, not specifically mentioned for August pruning, generally requires pruning after flowering to shape and encourage bushier growth. Heavy summer pruning is usually avoided due to bleeding sap and stress.
In summary, Wisteria benefits from a two-step pruning process including August, perennials and some shrubs can be lightly pruned or deadheaded in August, while hydrangeas that flower on old wood and many trees/shrubs should avoid summer pruning to protect flower buds and prevent vulnerable new growth. Protect your hands while pruning thorny roses with garden gloves, such as best sellers from Amazon.
Consider pruning your Wisteria plants after their summer bloom, shortening the long, whippy green shoots to encourage flower bud production for the next year. Additionally, August is an ideal time for light pruning or deadheading of perennials such as yarrow, bellflower, asters, lavender, hardy geranium, lady's mantle, bearded iris, and bee balm to improve their appearance and promote fall blooms.
