Trim Your Hedges Properly

Leggy, woody, and unsightly. It’s not a roll call for a fairy tale cast. It’s the perfect description of that sad-looking hedge in your yard if you’re anything like most people.

A row of densely planted shrubs can make a beautiful way to mark boundaries and keep pets and children safe and provide shelter for birds. Hedges require regular watering, feeding, and pruning in order to be healthy. Even though people forget to give their roots water in hot weather and to fertilize in spring with a 10-10-10 formula in the early spring, this is where most people really fall short.

Roger Cook, a This Old House landscaper, says that pruning is something many people fear. However, it’s an art anyone can learn. You just need to know a few basics.

These expert tips will help you maintain your hedge plantings.

How to Keep Your Hedges Healthy

1. Hand-pruning is essential in conjunction with shearing

To remove branch tips and stimulate bud production, you can use shears, whether hand-held or power, with long, scissor-like blades.

As the buds multiply, shrubs can become so dense that it blocks sunlight from reaching its interior, which can prevent interior growth. This results in a hedge that grows larger every year but looks dead inside. Proper pruning allows sunlight to enter and allows you to trim back shrubs to keep them from getting too large.

To allow light and air to enter the artificial hedge screening, make sure you use bypass hand pruners at every shearing. Reach inside to clip a branch at a 45-degree angle every few feet. This is just above a leaflet or nub that’s growing in the direction you wish to encourage.

You will need to rejuvenate a hedge that is very overgrown or old. You can remove up to one-third of the thickest stems at the base of your plant and stimulate new growth. Repeat the process next year. You will have a healthier shrub, which is smaller.

2. Prune in winter

Hedges should be cut in the late winter when they are dormant. This is especially important if you’re cutting back. Roger says that you don’t want your plants to break buds before you prune. This is because you want the plant to use its energy to produce new growth. You’re reducing the plant’s energy and making it take longer to grow a hedge.

Particularly evergreens need to be pruned early in the season. Evergreens are generally slower-growing and will likely become bare (where interior cutting has been made) and yellow at the tips as new growth begins to emerge.

Privet, viburnum, and spirea are faster-growing deciduous hedges. The golden rule for pruning flowering shrubs is to wait until the day after the blooms turn brown. This will allow the plant to set buds next year and can continue to bloom on the same season’s wood.

The tips of fastigiate white pines can be hand-pruned to reduce their overall size.

3. The hedges should be wider at the top and narrower at bottom

If left alone, most hedges will begin to grow at the top where they get the most sunlight. This creates a V-shaped shape that shades the lower branches, resulting in less foliage. Roger says, “You want that V to be upside down.” Roger says that a sheared hedge should be wider at its bottom and narrower at its top, regardless of whether it is flat, pointed, or rounded.

Start at the bottom, and work your way up to the top when shearing. Roger prefers to use his eyes to achieve a natural look.

Because it doesn’t shed as much snow, buzz-cutting the top of a plant can make it more susceptible to snow damage (broken branch). For winter, tall hedges can be tied up. Just make sure you use rope or chain lock (plastic tree-guying material) instead of hose-covered wire. This can cause trunks to become girdled if left on for too long.

4. Before you plant your hedge, decide how tall and wide you want it to be.

Start from scratch and choose plants that are able to make a hedge. This means that they will naturally grow tall and straight. The name ‘columnar’ or ‘fastigiate’ indicates this type of growth habit.

Formal hedges require shrubs that can withstand shearing and frequent pruning. A hedge should be at least 3 feet wide. Maintaining your hedge at eye level is the best way to make maintenance easy. Otherwise, you will need to climb a ladder in order to reach the top.

It is important to determine how tall and wide your hedge should be before you plant it. Roger says that it is important to research the habits of any plants you are considering hedging, and then choose a variety that will not overgrow your space. You’ll have to fight an uphill battle to trim the hedge to its proper size.

Western arborvitae and eastern red cedar are good choices for evergreen hedges with larger shapes that don’t require much pruning. You might also consider informal hedges made of flowering shrubs such as rugosa roses, lilacs, rose of Sharon, crape myrtle, and hydrangeas where four-season foliage is not necessary.

5. Learn the difference between privacy and hedge plants

A hedge should not be expected to give you privacy or block out unwanted views. Privacy plantings can reach 30 feet. Hedges should be maintained between 6 and 8 feet in height. Screen plantings can be much wider and include a mixture of evergreen and deciduous shrubs, perennials, and shrubs. This gives them a natural look. Roger says, “Let a fence be a hedge–an attractive shrub boundary that encloses and unifies your yard.” If privacy is what you want, look at large trees.