August Pruning Essentials for Gardeners: Focus on these 7 Plants to Keep Them Healthy - Cut back these blooms and bushes straightaway to avoid late-season damage
August Pruning: Maintaining Garden Health Across the US
August is a crucial month for garden maintenance, as many plants have finished blooming or benefit from a refresh to encourage a second bloom cycle and maintain form. Here's a guide to the best plants to prune in August, tailored by species and regional climate considerations.
Bottlebrush (Callistemon)
Prune your bottlebrush shrubs after flowering to keep them compact and bushy, encouraging new growth before winter. These drought-tolerant plants thrive in sunny yards, making them an ideal choice for a warm and dry spot in your garden.
Japanese Holly (Ilex crenata)
In cooler hardiness zones like 4 or 5, shape and trim Japanese holly as topiary or hedges to harden the plants before frost. It's essential to prune these toxic plants no later than two months before the average first frost.
Lavender
Deadhead spent flower spikes on your lavender plants to encourage a second bloom and keep them compact. Avoid cutting into woody bases to prevent damaging the plant.
Wisteria
August is the perfect time to prune wisteria for shaping and preparing for the next bloom cycle. Remember to prune twice a year, once in winter for hard pruning and training, and again in August for thinning and cutting back long whippy new stems.
Perennials
Light cutbacks, deadheading, or trimming in August will refresh perennials such as catmint, bearded iris, wild bergamot, coreopsis, salvia, garden phlox, yarrow, bellflower, asters, bee balm, hardy geranium, and lady’s mantle. This action promotes late blooms, controls size, and helps remove diseased parts before winter.
Bushes and Hedges
Light trimming to maintain shape and remove damaged, diseased, or dead branches is recommended for bushes and hedges in general. Heavy pruning should be avoided or done very carefully.
Climbing Hydrangea and Box (Boxwood)
August is also the ideal time to prune climbing hydrangeas and boxwood to maintain shape and health. For climbing hydrangeas, prune after the white flowers turn brown to maintain shape and encourage growth. A telescopic ladder is recommended for pruning climbing hydrangeas that cover tall exterior walls.
Thyme
Creeping thyme should be trimmed after flowering finishes in August to keep it compact and bushy. For pruning thyme and other herbs, the author recommends using Felco F2 pruners.
Tips for Tools and Timing
When pruning in August, it's important to keep tools clean and sharp. Using an Okatsune sharpening stone can help ensure your tools are always ready for use. Also, remember to prune at least 6-8 weeks before the average first frost to allow plants to harden off, particularly in colder zones like 4 or 5. In warmer zones, pruning windows may extend later into the season.
For a native, non-invasive wisteria, try the 'Blue Moon' American wisteria. French lavender, available via Walmart, is a good option for adding a new plant to patio pots this year.
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- To maintain a well-groomed home-and-garden lifestyle, August is a crucial month for pruning various plants to encourage new growth and maintain form.
- Garden tools, such as Felco F2 pruners, should be kept clean and sharp to ensure effective pruning, particularly when maintaining shape and health for plants like climbing hydrangeas and boxwood.
