Willamette Valley, Zone 8b
Pruning is an art form. Consequently, there are eleventy-one ways of doing it well. However, there are a few guidelines that will help you feel confident that your actions will help and not harm your tree or shrub.
Dormant Season Pruning of Fruit Trees, Shrubs, and Canes
December through February is a good time to prune most fruit trees (except cherries). As well as cane fruits like raspberries, blackberries, and elderberries. Wait for a hard frost in January to do your grapes, and February for blueberries and roses.
Most fruiting trees and shrubs benefit from dormant season pruning. Removing branches in the winter will concentrate the tree’s stored energy for an improved fruit yield, rather than vegetative growth and more fruit of lower quality.
Fruit Tree Pruning Rules of Thumb
- Take less than 30% of your fruit tree annually to avoid stimulating a survival response that creates excessive weedy growth.
- Cherry trees: Summer prune to discourage growth. Cherry trees are generally vigorous growers and will quickly lift the fruit out of reach. Wait until fruit production is done, then prune in late July through August to remove energy from the tree to slow its growth rate.
- Use clean, sharp bypass shears. Bypass shears work like scissors with two sharp blades, anvil pruners tend to crush branches.
- When using a pruning saw for larger branches. (Over an inch.)
- Undercut the branch just through the bark.
- Move to the left and cut from the top to remove the weight of the branch.
- Undercut again near the collar.
- Then finish with a clean cut through the top.
- These steps prevents the bark from peeling like a banana when the branch breaks during sawing.
- Disinfect tools between trees. Spray alcohol, or alcohol wipes will do the trick.
- Take more thinning cuts (cut back to the adjoining trunk or branch) and fewer heading cuts, (cuts to the middle or tip of a branch).
- Remove broken or dead branches.
- If branches are rubbing on another, remove the weaker one.
- Cut a branch back to the wrinkled bark (collar) for better healing. Don’t leave a nub that will rot and become a source of infection.
- For more detailed pruning information, check out these books out from your local library:
- Pruning Trees, Shrubs & Vines What When & How Published by Storey Publishing. ($3.95 for a super accessible primer with helpful illustrations.)
- “How to Prune Trees and Shrubs: Easy Techniques for Timely Trimming”, by Barbara W. Ellis
- “Backyard Orchardist: A Complete Guide to Growing Fruit Trees in the Home Orchard”, by Stella Otto
Tip: Each specific species has a preferred pruning method. If you need a primer for pruning apple trees, make sure you look up methods specific to apple trees.
First thing to understand is the growing habit of your variety.
For Erect and Semi-Erect Varieties:
These have strong upright growing canes. I have Triple Crown which is a semi-erect variety.
Dormant Season Pruning:
- First remove any very old, damaged, pest infested or diseased, or dead canes.
- Top all rangy canes to be about 5’ tall.
- Trim all lateral branches to be 1’ – 2’ long.
- Top all new canes (primocanes) when they reach 5’.
- Cut back lateral branch growth as necessary.
- Remove any sick or dead canes.
These don’t have much internal support and need to be trellised. Marionberries and tayberries are common trailing varieties.
- Do not tip the canes of trailing blackberries, let them grow to be a long as they want.
- Let two new canes per crown grow, wrapping them around your trellis. (I have a tall 6’ trellis with several wires, I wind them around the wires.)
- They generally don’t fruit the first summer.
Year Two and Beyond:
- The trellised canes should fruit the following summer.
- Let two new canes emerge from the crown and allow them to trail along the ground. Trim back any others.
- The trellised canes that produced fruit will die during winter. Remove those, then retrieve the younger canes that were allowed to trail and wrap those ones around the trellis for the upcoming season.
These are separated into two groups:
- Primocane fruiting: Produce fruit in year-one AND year two-canes, then die back.
- Floricane fruiting: Produce only on year-two canes.
I have Heritage raspberries which are a primocane fruiting variety. The first year canes put out a crop of late season berries at the very top of the canes. So canes should be allowed to grow as tall as they like. Next season, those same canes will put out some small lateral branches and flower and fruit again. After their second fruiting the canes die in the dormant season and need to be removed.
Floricane fruiting varities of raspberries can grow a little crazy tall and need to be topped at about 6 feet. Let them grow to the top of your trellis and cut off the top. Then in year two, they will produce fruit during the summer and die during the dormant season. Since you get new canes every year, after year two you should have a steady supply of fruiting canes. It’s a cycle of topping in the spring, then removing dead canes in the dormant season.
President’s Day is for Roses & Blueberries
These two plants both appreciate a hard pruning right before they put on spring growth.
Since there are so many different forms of roses it is important to know what type you have and follow a guide meant for that type. I have tea roses of a color variety known as Tropicana. It was the favorite of my husband’s grandfather who was a Royal Rosarian.
To prune tea roses, first remove any dead canes. I like the “open vase” form, so I take out any canes growing directly up from the crown. Remove any root suckers. Then prune all the canes down to just above my knee height. I like to side-dress them with epsom salts and wish them well.
During the summer, remove leggy canes and root suckers as needed. Also deadheading will prompt a continuous supply of fragrant flowers. Sometimes I get aphids and blackspot, but I don’t treat either. Aphids are a food source for beneficial insects and blackspot is gross, but doesn’t seem to affect their overall health.
Once blueberries are beyond three years old, they require vigorous pruning in order to maintain a good fruit set. That means bigger, sweeter fruit and less disease potential.
How much is” vigorous pruning”? On a well established bush we need to remove 50% – 75% of the fruiting wood. That’s a lot right?
It’s OK, really. Fruit is produced on canes that are 3 to 6 years old. So we need to remove the 7th year canes (very woody looking) to stimulate new cane growth. On each of the target 3-6 year old canes we need to remove a lof of the weaker fruiting wood. This concentrates the energy that is currently stored in the root system on the strongest branches. It also allows sunshine to penetrate the plant for photosynthesis and reduces disease pressure by allowing sun and air to more thoroughly dry the plant after a rain.
Check out this video from University of Maine. You will feel much more confident—I promise.
Check for Pests and Disease
While pruning, keep a sharp eye for signs and symptoms of diseases. Refer to OSU’s Managing Diseases and Insects in the Home Orchard for identification and treatment options. I also make use of the Ask an Expert part of the Washington County Master Gardener website. They have been extremely helpful in identifying pest and disease issues and suggesting resources and IPM strategies.
Pruning Tips for Popular Ornamental Shrubs
Hydrangea and Azaleas: Prune or deadhead just after flowering, but not after August or you risk cutting away next year’s flowers.
Rhodendron: Prune in late winter. Perhaps adding to your President’s Day pruning list.
Questions? Feel free to drop any questions in the comments section, or email me at email@example.com
- OSU Extension: Growing Blackberries in your Home Garden
- OSU Extension: Growing Table Grapes in your Home Garden
- OSU Extension: Growing Raspberries in your Home Garden
- OSU Extension: Growing Blackberries in your Home Garden
- OSU Extension: Growing Blueberries in your Home Garden
- OSU Extension: Pruning Roses
- OSU Extension: Pruning to Restore and Old Neglected Apple Tree
- OSU Extension – 10 Minute University: Pruning Made Easy
- Video OSU Extension: Apple Tree Pruning
These books give me the confidence to get out there and start cutting. The one on the right gives the essential information, no fluff, and great illustrations for less than a latte. (No judgment there, I do love my blended coffee!)