The Philosophy of Pruning
Print this page
It’s easy enough to get out the loppers and hack away at your plants. It takes a little more prep work but ultimately is far more satisfying to take some time to understand what you want to accomplish and how best to do it (or “to prune with a purpose”). Below are some guidelines for your attack.
Generally if you’re about to haul out the loppers, there’s a reason:
- Removing dead wood
- Formative pruning
- Regenerative pruning
- Hedge trimming
There are some things you’ll need to know to be successful:
- Pruning tools
- The right way to prune
- The wrong way to prune
- Deadheading
Removing Dead Wood
Dead wood can and should be removed whenever necessary. However, be sure it is dead. Dormant wood can be deceptive. Scratch the bark and look for green before you cut. If you suspect the wood is diseased, disinfect your pruners between cuts and again after pruning by dipping them in 10% bleach solution.
Formative pruning
(To control size, enhance the shape, correct structural defects, preventative maintenance, and to encourage certain growth habits.) Usually this type of pruning is done in early spring, before the plant “leafs out,” when the limbs can best be seen and the clean up is easier.
- Woody plants can be pruned to change their growth habit and control their size.
- Lower limbs can be pruned to expose attractive trunks or to create clearance.
- Limbs growing in one direction can be removed to encourage growth in another.
- One of two rubbing limbs can be removed, as can one of two terminal shoots, to strengthen the total tree.
- Spindly branches that might break in winds or under snow loads can be pruned.
- Suckers should be removed from the base of trees.
Regenerative Pruning
(Thinning and cutting back to rejuvenate or increase flower buds.) Many shrubs need periodic hard pruning to promote vigorous new growth. One way to do this is to prune the oldest 1/3 canes of the plant all the way to the base. This can be done each year for three years, if necessary. Another way is to cut the entire shrub back to 6-12" in the early spring. The method will depend on the shrub, its flowering time, and what you hope to accomplish.
Fast growing shrubs can become leggy and weak. Thinning back to fewer but stronger stalks strengthens the plant.
Hedge Trimming
Creating and maintaining a dense hedge will require pruning. Be sure to shape a hedge wider at the base than at the top, so light hits all the surfaces. Otherwise, the hedge will be full on top and sparse beneath. Pruning can either be formal, with hedge shears or trimmer; or more naturalistic, by hand with pruners. Hedge trimming should be done in early spring before the shrub pushes out new growth. Prune again in late June/early July, after the flush of growth, if necessary. Prune no later than the end of July, to allow tender shoots to harden off for winter.
Pruning Tools
All tools should be sharp and fit well in your hand. A hand saw, hand pruners, loppers and/or pole saw are each excellent tools, used in the right place. The rule of thumb is: up to ½" branch, use hand pruners; up to 1" use loppers; over 1", use a saw. Never prune anything taller than you can reach comfortably, or larger than you can comfortably lift. Any large or tall trees should be handed over to a trained arborist. Pruning can be dangerous work!
The right way to Prune
- Make all cuts clean, with sharp tools
- When pruning trees, never leave stubs. Stubs won’t heal over correctly.
- Equally important, never cut too close to the trunk. A cut just outside the branch bark ridge will allow the wood to grow over the wound.
- Paint isn’t necessary on clean cuts. In fact, recent research has proven it may be detrimental. Let the tree heal itself!
- Prune back to just above a leaf node on shrubs, trees, and broad leaf evergreens.
- Disinfect tools after pruning.
The right time to prune
- The best time to prune almost everything is early spring, just before it leafs out.
- The exception will be spring-flowering shrubs and trees that flower on last year’s wood.
- With spring flowers, make a decision as to whether form or flower matters more to you, then prune either early spring or after flowering, depending on your decision.
- Prune lilacs no later than two weeks after they flower! They set flower buds for the next year almost immediately!
Deadheading
Deadheading broadleaf evergreens is good for them. Pinch the bloom off just after flowering, before the plant can set seed. This helps the plant direct its energy into leaf production and promotes bushier growth.
Not all plants respond the same way to the same treatment. Feel free to ask one of our sales associates about the best time and method to prune to accomplish your purpose!
Helpful pruning guide for common landscape shrubs
| Shrubs | When | How | ||||
| Barberry | Early spring | Little pruning required except to remove a few old branches occasionally to encourage new growth. Head back as necessary to keep plant in shape | ||||
| Butterfly Bush | Early spring | Cut out all dead wood. Remove some old branches and head-in as necessary to keep plant properly shaped. | ||||
| Clematis | Spring | Cut out weak growth but save as much old wood as possible. | ||||
| Crab (Malus var.) | Early spring | Prune moderately. Cut out dead and broken branches and suckers. | ||||
| Deutzia | After flowering | Remove a few older branches and all dead wood. Do not let growth get too dense. | ||||
| Dogwood, flowering | After flowering | Remove dead wood only. | ||||
| Dogwood, other | Spring | Varieties grown for colored twigs should have the old growth removed to encourage brighly colored new shoots. | ||||
| Elderberry | After fruiting | Prune severely. Remove one-half of the season's growth. | ||||
| Forsythia | After flowering | Remove a few older branches at the ground each year and head back new growth as necessary | ||||
| Honeysuckle, Bush | After fruiting | Cut out some old branches. Keep bush open | ||||
| Hydrangea | Early spring | Hills of snow variety: cut back to ground. Others: remove dead and weak growth, cut old flowering stmes back to two buds | ||||
| Laurel, Mountain | After flowering | Prune very little. Remove a few old branches at the ground from weak, leggy plants to induce growth from the roots. | ||||
| Lilac | After flowering | Remove diseased and scaly growth, cut off old flower heads, and cut out surplus sucker growth | ||||
| Mock-Orange | After flowering | Cut out dead wood and a few old branches to thin out plant | ||||
| Rhododendron | After flowering | Treat same as Laurel, Mountain | ||||
| Roses, Climbing | After flowering | Cut out about one-half of old growth at the ground and retain the vigorous new shoots from the root for next year’s flowers. Head back as necessary. |