Important Pruning Tips from Landscape Pros

Lee ArmilleiField Notes

So your landscape is filling in, and it looks simply gorgeous, but for how long will it last? Often the key to maintaining a healthy, vigorous garden is actually to cut it back. Promote the kind of growth you want and manipulate plants for their best features by pruning.

Definitions

To get started, let’s define some general pruning terms:

Prune

Selective cuts made using a sharp tool to specific locations on a woody tree or shrub.

Prune plants to remove dead wood; alter the shape or size of the plant; allow more air flow through the plant; and encourage specific branching habits.

Cut above a node on a branch or stem, to encourage more branching. Or remove the branch entirely by cutting just above the branch collar.

Prune large branches in three cuts. Do not cut into the branch collar.

Dead-head

To dead-head is to remove spent or wilted flowers from annuals, perennials, and occasionally shrubs.

Dead-head to prevent the production of seeds after a plant flowers. Plants require a lot of energy to produce seed and will use that energy instead of flower production. In plants such as herbs, the desirable trait is the foliage. Pinch flowers off as soon as they begin to develop so that energy goes into flowers, foliage, and flavor.

To dead-head perennials and annuals, pinch the flower between fingers to remove it from the plant. Remove flowers from woody plants with pruners.

Cut-back pruning

To “cut a plant back” means to reduce the size of the plant. Cut back some shrubs by less than 1/3 to keep them healthy. Cut others all the way back to six inches for the best stem color and size. Know your shrubs before you prune! If you need help, hire a gardener to do it for you!

Cut back perennials and grasses in the spring. Leave perennials up through the winter to add beauty and interest in your garden. Hollow stem perennials also provide nesting places for pollinators and other insects. Wait until nighttime temperatures are consistently over fifty degrees or use these tips to figure out the best time in your yard.

Shearing

Shearing means to cut all of a plant to one plane. You will often see boxwoods, cherry laurels, or privet sheared into spheres, boxes, or other shapes.

Shearing provides an immediate, neat-and-tidy look. However, the pruned branches will not grow back at the same rate, so those shrubs may soon look raggedy. The solution is shearing again.

Basic pruning principles

Whether you’re pruning or cutting back, the best place to cut is usually on the stem, right above a leaf or branch.

For a safe bet, prune trees and shrubs immediately after the plant flowers. You can always prune in late-winter or early-spring, however, some plant species bloom on old-wood and will not bloom if these buds are removed.

Pruning specifics

Pruning Hydrangeas

Some hydrangeas, specifically Big-leaf Hydrangeas (Hydrangea macrophylla) and Oakleaf hydrangea (Hydrangea quercifolia) flower on old wood. They generally don’t require much pruning if they are in a good location in your garden. But if you want to prune them for size, cut them back immediately after they bloom. This will give them time to set flower buds for next year.

Other hydrangeas, namely Smooth Hydrangea (Hydrangea arborescens) and Panicle Hydrangea (Hydrangea panniculata) bloom on new wood. Prune them in winter or early spring without risk of loosing blooms.

Pruning Lavender and sub-shrubs

Prune lavender in the early spring to remove any dead branches that did not survive winter weather.

To shape lavender plants, make cuts in the green, fleshy tissue, not the wood at the base. Prune to the shape desired and then use the cut lavender stems rather than composting them. Tie stems together, dry them indoors, and then use them for decorations or to make lavender sachets.

Depending on how many shrubs you have, you can either hand-prune each one by gathering a handful of stems and using pruners to prune sections at a time, or you can pull out the hedge-trimmers and get a whole lot done fast! The sooner you can do this after flowering, the longer stems have to re-grow and provide the old-wood needed for a floral display next year.

Pruning Perennials for size and blooms

Extend bloom time or the size of perennials by cutting them back by late May or early June. Cut back the height of a planting by one third to reduce its size and prevent the plants from flopping. Or, cut back the front section of a planting to delay its bloom. This will result in the pruned sections blooming later than the unpruned sections with an overall longer bloom time.

Basil

Most people know to dead-head basil plants to keep them from going to seed and tasking bitter. Pinch the stems back, immediately above a leaf set. At each pinch point, two new stems will grow, creating a bushier plant. The pinched stems last for a week or more in a bud vase on the kitchen counter.

Remember, this is your garden, so have fun with it! Try different pruning techniques each year to see what works best for your property. Use these tips to shape, prolong the bloom period, and increase the health of plants throughout your property.

And if you need help, contact us!