Tips Misc-Pruning

Pruning helps to keep our plants healthy, improve their structure and appearance.  In this section we will help you identify the right season for your plants, the methods and tools to use.

Why We Prune

There are 5 primary reasons why we prune.  These are:

  • Remove a danger or safety issue.
  • Remove dead or diseased plant parts.
  • To shape or contain a plant to its space.
  • To encourage and enhance flowering and fruit.
  • To repair or rebuild a plant.

The Brooklyn Botanical Garden has a great webpage on Pruning – the Why and When.  Check it out for lots of great information.

Pruners
Loppers

Tools

First let’s talk tools.  Every gardener should own a good pair of Pruners, a Lopper, a Garden Hand Saw and a pair of Sheers.  With these four tools the home gardener can tackle almost all pruning projects.

All these tools can be purchased at your local garden center or online.

Important Note:  If you feel a pruning project is too big for you (e.g. removing a large tree limb), then it probably is too big.  Don’t take unnecessary chances, call in the professionals.  

Tree Hand Saw
Sheers
Tools – Bypass vs Anvil Pruners

Bypass pruners work like scissors, making a cutting action that is usually more precise and clean.  Anvil pruners use a crushing cut, pinching its sharp top blade against its bottom flat surface (i.e. anvil), crushing the plant material between, pinching it off.

Bypass are best for live plant material where exact, clean cuts are needed.  Anvil work best on dead material or thicker wood where more power is needed.

For more information on which to use where, see this excellent article from Davaon Garden Tools.

Tool Care

It is very  important to keep your tools clean and sharp.  A dull tool will do damage to your plants and possibly even hurt you as the unnecessary extra effort to cut into your plant increases your risk for injury.

Here’s an excellent video by a Master Gardner on how to sharpen your pruners & loppers.  We encourage you to search the internet for other videos and articles on tool care.  Whatever you do though, keep them clean, sharp and in good working order.

When to Prune

Pruning is a task that is best done from Winter to mid-Summer, but every plant has its season for pruning and its season for not pruning.  Therefore it is important to know when is the right time to prune your plants. 

Fall generally is not a good season for pruning as pruning promotes new growth which may not harden off before the freezing weather comes leading to winter kill.  

We’ll try to help you find the right time to prune your plant, but if in doubt, ask the experts.  Try your garden centers, your local cooperative (Rutgers EDU is an excellent choice for our area) and the internet.  When using the internet be mindful of our zone (7A) and the zone the internet article is covering.

There are two types of pruning that can be done at any time regardless of the season:

  • Dead or diseased parts of the plant.
  • Limbs or branches that pose a danger to people.

In both of the above, especially the latter, there is not bad time to prune.  When evaluating dangerous limbs make sure you have the tools and skills to handle the job.  If you’re the least bit unsure if it’s a job you can handle, then get professional help.

Here are some good sites to help you decide when to prune your plants:

Winter Pruning

Winter pruning occurs during the dormant period for your plants.  The hardwoods are best pruned in late Winter:

  • Quercus (Oaks)
  • Ulmus (Elms)
  • Sorbus (Ash)
  • Malus (Apples)
  • Crataegus (Hawthorn)
  • Pyrus (Pear)
  • Dogwoods (Cornus)

Please take special care of yourself when pruning bigger trees.  If you’re climbing ladders or the branch you want to prune weighs more than you, consider bringing in the professionals.

Spring Pruning

It’s a lot easier to spot deadwood in the Spring as trees & shrubs start to bloom.  Spring is also the right time to prune your fruit trees. Either just before they bloom in early Spring or a little later after their flowers fall.  

Summer flowering shrubs generally flower on new growth, so pruning these in early Spring will promote new growth and not hurt your summer flowers.  These include Butterfly Bushes, Caryopteris, Cotoneaster, Sumac and Spirea.

Butterfly Bush
Summer Pruning

Your Spring flowering shrubs are best pruned in late Spring or early Summer, after their flowers are spent and falling.  This includes Barberry, Flowering Quince, Forsythia, Lilac, Crabapples and Wisteria.

Many trees should not be pruned during the mid to late summer periods due to prime fire blight conditions – hot & humid.  These include Apples, Pears, Ash, Oak, Hawthorn and Spiraea.

Lilac
Fall Pruning

As previously noted, Fall is not a good season to prune because pruning stimulates new growth and if that new growth hasn’t hardened off before the freezing temps come, then you risk winter kill.  The exceptions being dead or diseased parts of the plants, or limbs & branches that pose a dangerous situation.

Pruning Techniques

Below are the more popular pruning techniques for trees, shrubs and perennials.  There are plenty more techniques that we haven’t covered here.  We encourage you to search the internet for others, in particular how to prune your specific plant to see if there are any special considerations before you take the pruner to it.  Also try YouTube if you want to watch your plant being pruned.  Odds are there exists a video of your plant being pruned.

Here are some great references for Pruning:

Pruning General Guidelines

These guidelines are provided by University of Minnesota Extension: 

  • Remove diseased, broken or dead branches.
  • Remove downward-growing branches.
  • Remove crossed & entangled limbs, keeping just one.
  • Remove suckers coming up from the roots or low on the trunk.
  • Remove vertical branches (watersprouts).
  • Make pruning cuts close to the branch collar at the base of the limb.
  • For larger limbs use the 3-cut method (see below).
  • Remove large limbs first, working towards the smaller limbs.

For young trees prune to shape the tree without cutting the central leader.  Important to shape the tree while it’s young to help avoid a heavier prune down the road.

Pruning Flowering Shrubs

You want to prune to open up the plant, allowing air and light in, reducing the chance for disease and helping promote new bud growth.

Important: Spring flowering shrubs should be pruned after they flower, while Summer flowering shrubs should be pruned in the Spring.

Use the General Guidelines listed above and consider these additional steps:

  • Remove about one-third of the oldest wood at the ground level.
  • Remove about a third of the younger, stalks to a third of their height each season.

Make pruning always about cuts 1/4 inch above the bud, sloping down and away from it at a 45 degree angle. Select a bud in the direction you want the new stem to grow.

For more information visit the Rutgers Cooperative Extension site on Pruning Flowering Shrubs.

Heading v. Thinning Cuts

Heading technique involves pruning the outer, top portion of the tree/shrub, even cutting the leader.  This is used to promote a bushier plant with many new shoots.  As much as a third of the plant is removed.  This technique is usually done on fruit trees to promote more fruit.

Thinning technique cuts limbs back to either a parent branch or the trunk/leader.  Thinning promotes air circulation and structure to the plant.

Here is a useful website from Sustainable Macleod on Heading v. Thinning.

Here is a good video by Marlene Simon on heading and thinning pruning techniques. 

Dead Heading

Deadheading is pruning old fading flower and seed heads from the plant to promote new growth and re-flowering.  As blooms fade, pinch or cut off the fading flower just above the first set of healthy leaves. 

Deadhead as often as the plant needs it, which for some plants could be a weekly or even a daily task.

Weather plays a part here as heavy rains and extreme heat can fade flowers more quickly.  But deadhead them back, drain over watered plants or water under water plants and you should get a new crop of flowers.

3-Cut Method

The 3-cut method is used for tree limbs that are too big or heavy causing the limb to tear away as the weight of it falls.

The first cut (A) is made about 12-18″ from the final cut (C).  This is an undercut of about a 1/3 of the way through the limb.  The second cut (B) is made about 8-12″ from the first cut (away from the trunk).  This cut is made completely through if it doesn’t tear away to cut A.

Now the weight is off the limb you can make the 3rd cut (C). This is made at the collar of the limb.

Here is a good video by Roger Cook of ‘This Old House’ on the proper way to do the ‘three-cut’ method. 

Shearing Method

Shearing is the removal of the outermost leafy layer of growth around the whole plant with the goal to improve the shape for aesthetic purposes.

Typically hedges, boxwoods and foundation plants are shearing targets as home owners want to keep these at a certain size and shape.

You should still consider pruning too at this time, to remove dead, diseased and problem limbs (see Pruning General Guidelines above).

Here is a good YouTube video by Polo Fields Lawn Service showing the different Shearing techniques and tools.

Red Twig Dogwood
Red Twig Dogwood - Coppiced
Coppicing Method

Coppicing method takes a tree or shrub right down to the ground.  Although coppicing sounds drastic, for centuries it has been a well used method to promote new vigorous growth.  It originates in tree harvesting, collecting the cuttings for commercial purpose while leaving behind the roots & crowns to build the next crop.  Your average home gardener is unlikely to be interested in coppicing trees, however, small shrub coppicing has a lot of value.

Coppicing small trees and shrubs encourages a broader plant and can promote some interesting coloring of stems.

Home garden candidates to coppice include:

  • Dogwoods
  • Hydrangea
  • Willow
  • Holly

Most needle leaf plants (e.g. pines) will not survive a coppicing.  Check with your local cooperative or tree expert whether coppicing is an option for your tree or shrub.

Coppicing is best done in the late Winter or early Spring.

Typically you want to leave the stumps close to the ground, however the variety of plant will dictate how much to leave above ground.  Have your stumps cut at 15-20 degrees from flat, facing south to help eliminate standing water on your stumps.