Less pruning and less stress are win-wins for you and your shrubs in summer.
Hedges — rows of plants intended to form a solid shape as a screen or wall — can be one of the most high-maintenance plants to maintain because they must be trained and pruned appropriately from an early age and clipped appropriately to conform to hard-edged geometry without weakening the plants. It’s an art form and a skill for sure, but without proper technique it’s easy to ruin long-lived plants.
In summer, you don’t have to go far to find commercial hedges that’ve been shorn too hard, leaving thin shells of leaves and bare twigs exposed to scorching sun. High-maintenance techniques like hedging and topiary are mistakes to avoid repeating at home.
At its best, your own pruning should increase plants’ health and vitality while doing the least amount of damage. An example: removing dead, diseased or crossing branches as we do with trees in the proper tree pruning season (winter.)
But when it comes to shearing and hedging during the hot season, we must educate ourselves, know the plant we are working with, and anticipate how it will react to the cuts we make – because by making a cut, we activate growth cells that might have been inhibited, forcing the plant to use its available water, nutrients and other resources to regrow delicate new leaves at the hottest time of the year.
In Texas, hedges are initially pruned to force low branching, and maintained with the top narrower than the bottom (so the bottom isn’t shaded by a wide top and sunlight can reach all of the leaves).
A healthy, young hedge can adapt or overcome pruning more easily than a plant stressed by weather, age or disease. So once a hedge has been trained, the severity with which we prune that plant should never exceed the ¾ that experts recommend. Remove no more than a quarter of the foliage length and even less in extreme conditions.
Typically, twice a year is all that is needed to maintain an evergreen hedge, depending on the species, weather and desired outcome:
- In a perfect world, especially for spring bloomers, give evergreen broadleaf hedges a cut after the danger of freeze has passed and following their flowering period; if any, before they’ve grown more than a foot.
- A second light hedging during the hot season is performed to maintain form and remove any over-enthusiastic stray or out-of-bounds branches.
Remember to be very careful after August because new shoots can be very susceptible to cold burns when winter approaches.
Keep in mind that severe and constant pruning can cause the plant to exhaust all its resources and not be able to produce more, leaving a plant weak and unable to resist insects and diseases.