Pruning recommendations vary by the farmer, consultant, and even the University researcher. Some advise to prune trees hard to regenerate growth (not so much in CA anymore), some suggest that only a few limbs be removed annually, while others advocate throwing away the pruning shears. With these differences in opinion, what is the proper way to prune a tree?
Young Orchards:
Research has shown that reduced pruning on younger trees can lead to larger, earlier yields. This is mostly due to increased canopy that is able to produce crop. Some research has found early benefits of leaving young trees unpruned, but have found that over time, these branches will split when the crop load begins to increase leading to yield loss. Hence, some structuring of first and second leaf trees is recommended to address tight branch angles and close proximity of scaffolds, which leads to included wood and weak branches.
Scaffold selection on young trees should be based on growing conditions. There is no set number that is ideal, and a farm level decision should take into account tree vigor, spacing and management practices. Heading the trees higher at planting (42” or higher) will provide more opportunity to select scaffolds, but will increase pruning time. Heading the trees too short may lead to issues with shaker head placement at maturity, leading to more bark damage. After the first year of growth, select scaffolds with distance in between and avoid scaffolds on the same plane and height of the trunk of the tree. By spacing the scaffolds vertically and around the tree, the growing limbs will be better attached, leading to less breakage. Remove steep angled limbs as these are often weaker. Limbs with a 45-60 degree angle are ideal. Avoid hard heading cuts as cutting the tree back too hard can spur lanky, vertical regrowth the following spring. My experience has shown that cutting trees back to a wood diameter of ½” to ¾” diameter generally provides the desired growth response. Finally, remember that less vigorous varieties and trees will require less pruning than more vigorous trees.
After the selection of scaffolds in the first year, not much pruning is needed. Typically, 1-2 cuts per tree is needed after the second growing season to remove limbs that are vertical or crossing over the tree. Limbs that are too low and are in the path of orchard operations should also be removed. After the third growing season, pruning should focus on removing limbs in the way of operations.
Mature Orchards:
Mature tree pruning should be minimized but not neglected as maintenance pruning does need to occur. Typically, maintenance pruning is performed as thinning cuts to remove limbs that are in the way of operations or to help develop the desired architecture of the tree. Keep in mind, however, the results of multiple research trials that have shown no yield benefit from pruning mature trees. These long term studies from Kern, Colusa, and Stanislaus Counties have found no yield differences within mature orchards. There are, however, reasons to prune mature trees, including: easier access, worker safety, increasing the amount of light to the orchard floor to assist with drying, and to remove broken, dead, and diseased limbs. Another reason that is often not discussed is to reduce pest and disease pressure. UCCE research out of the Sacramento Valley has shown a 6% decrease in navel orangeworm infestation in the upper canopy in pruned trees due to better insecticide spray distribution in the upper canopy.
Hedging- or making indiscriminate heading cuts in the upper canopy – mature orchards generally isn’t recommended. Even though this operation is useful for increasing the light on the orchard floor, it often leads to large sections of the productive canopy being removed. These heading cuts also create an odd regrowth pattern in which new limbs grow vertically. Instead, consider selected limb removal by making thinning cuts to help increase light penetration. This type of maintenance pruning may not be needed every year, allowing for the cost to be distributed over a three to four year period.
Pruning should only occur when rain is not in the forecast to avoid wound infections by pathogenic fungi that disperse spores during rain events. This is especially true with young, developing trees. Wounds can be susceptible up to two weeks after pruning, with larger wounds taking the longest to heal. Even with this healing time, pruning paints are not recommended as they can slow the healing process. Ongoing tests with biological agents have shown some promise, but they are still under evaluation. Pruning as late as leaf out will have no impact on tree growth.
Brad
December 14, 2018Interesting article. Can you provide a citation/link to the research comparing NOW damage with pruned vs. unpruned almonds? Thank you
David Doll
December 16, 2018I dont have the exact citation – but it was from work that Franz Niederholzer did at Nickel’s Estate. Here is an article he wrote about it a few years ago: https://thealmonddoctor.com/2013/12/19/pruning-improves-pest-control/
Hope that helps,
David
John Kluge
December 21, 2018When I am pruning I carry a spray bottle of 20% bleach which I spray on my saw and shears between trees to lessen fungal transmissions. I do this because that was the way I was taught to prune. Does this work? It usually results in very rusty saws and shears. Could I spray something on the cut itself to prevent the cut from getting spores in it?
JDK
David Doll
December 31, 2018Dear JDK,
Disinfecting pruning shears with bleach water will help reduce the transmission of fungal and bacterial diseases. Typically, we use 10% bleach water in experimental work, which has been shown to have a disinfecting nature. This will help reduce the rate of bleach (sodium hypochlorite).
In regards to other products, heat is also effective and isnt corrosive. There are other spray-able products, but 10% bleach water is probably the most effective. Cleaning the shears after each cut probbaly isnt needed, but should be done after cutting an infected tree. It is often advisable to clean shears after finishing a row to reduce any potential contamination.
When I use to cut fireblight in apples, we found that rinsing the shears with clean water and oiling immediately when finished did help reduce corrosion and increase shear life.
Hope that helps,
David
Yanik Allard
September 29, 2019Hello,
I bought a piece of land in Sardinia which has maybe a dozen mature almond trees, these have stunning flowers in late winter/early spring and give some fruits, not many though.
The problem is that these have been abandoned for possibly decades so some branches have died, some have lichen growing on them and some are healthy.
My local helper who seems to know a lot about local plants told me these could be rejuvenated by doing some very heavy pruning. Do you agree and how ‘heavy’ do you think we should go?
Many thanks for your help in advance!
Yanik
David Doll
October 2, 2019Yanik,
Pruning would help “rejuvenate” the wood, but if there are flowers, it may not be needed. There is a good chance that the flowers aren’t setting into fruit for other reasons. This could be water stress, nutrient deficiency, disease or frost. Before pruning the tree, I would start by applying a little bit of water in the fall to help rebuild carbohydrate reserves within the tree. Next year, a regular watering using a slow form of water application once to twice a month would be helpful. This type of low intensive irrigation is easy to do and should help increase the crop load in the future years (yes, water applied in 2020 mostly increases the 2021 crop). As a comparison, in farm operations they water regularly – sometimes daily depending on the irrigation system. I think this would be more work than you need to do for the 12 or so trees.
Finally, ask yourself – what do you want from the trees? If you enjoy the flowers in the spring, why prune them back? It will take 2-3 years for the limbs to redevelop. If a little bit of crop is what you are looking to produce, i think irrigation every 1-2 weeks would be the greatest help.
David
James
November 12, 2023Hi Yanik,
We have a similar situation in Mallorca. Did you go ahead with the heavy prune and how did were the results?
How Do Almonds Grow? Learn to Plant and Harvest an Almond Tree - The Public Goods Blog
February 20, 2020[…] you’ve finished filling in the hole, heavily prune your tree. You’ll want to remove anywhere from one third to one half of the branches. This clearing will […]
DeeDee V
March 22, 2020I have a basic and possibly stupid question. I get the scaffolding part of this, but what about the central leader? Should that be pruned to start the “vase” shape and if so when after planting? Next year during dormancy? I planted an All-in-one two months ago—barefoot. It has already leafed out nicely. Thank you.
David Doll
March 26, 2020DeeDee,
I wouldnt prune the tree too much. Almonds are more shrub-like in nature. Do remove a few limbs to open up the tree, but not much more pruning than that is needed. I would not prune the tree to a central leader structure (like an apple tree) as this doesn’t really fit the natural shape of the tree.
David
Dorian Dodson
March 30, 2020Thanks—it came with a central leader which was why I was puzzled (as well as some good scaffolding branches) and wondered if I should let that grow or prune it off. But I will heed your advice and not over prune!
David Doll
April 1, 2020Dorian,
Ah, I see. yes, the trees are delivered with a central leader due to the propagation method. Make a cut at about 42″ or so to remove the top part of the tree. Also, remove the lateral limbs by leaving a stub on the trunk of about a 1/2.” This will help develop the primary scaffolds. More information on planting new trees can be found here: https://thealmonddoctor.com/2010/12/27/proper-almond-tree-planting/
Hope that helps,
David
Sam
December 30, 2020I purchased a home 13 years ago here in coastal California. In the side yard, placed too close to the home was a large and in my opinion ugly mature tree. My first thought was to cut it down, but after awhile I grew to appreciate the shade and privacy it provides. I later determined it is an Almond tree.
I’m unsure of its age but its very mature. It flowers and produces almonds, sort of, they don’t look very edible. I have managed to find one baby tree from it. Anyway, my question has to do with heavy pruning or topping. Ive been told by a neighbor that I could prune the tree to almost nothing and it will grow back. I don’t want to go that extreme but would like to bring it down quite a bit. How far can I go without killing it?
Thank you.
David Doll
January 1, 2021Sam,
Sounds like it might be a seedling almond, which typically will revert to the wild type of bitter kernels and hard shells. Without knowing the size or issues with tree structure, I cant really provide clear guidance on how to prune. The question I have is: why do you want to prune it? If it is the shape and size you want, there isnt any need. If the tree is too big, thinning a few limbs map help reduce its height. If it is too “bushy,” removing a few (2-3) limbs to open up the center will help provide structure.
Pruning it back will not really help the tree – nor will it change the characteristics of the nut/kernel.
David
Patricia Allen
January 4, 2021On a few of our 5th leaf Independence there is a very healthy thick limb going straight up the middle. They originally were all pruned the same with the headers being cut, but a few must have grown a shoot off the header that then went straight up. I cant imagine taking off this limb, as it is one of the largest. The surrounding limbs are all normal. Should it be cut out to perfect the vase shape and let more light in?
David Doll
January 9, 2021Patricia,
Without seeing a photo, I am tending to agree with you and not removing the limb. Removing too much and opening up the center will most likely spur regrowth, which will be less productive.
Major structural cuts typically aren’t needed after the first three years.
Hope that helps,
David
Lisa Coggan
February 20, 2021Is it possible to train a very young almond tree into more of an almond bush? Is that even a thing? LOL. We are limited with width space To about 3 ft.², not Limited for height
Thank you
David Doll
February 20, 2021Lisa,
No problem in training the tree into a bush. Almonds tend to be more shrubby than a tree – and only have a defined trunk because of how we train them. Feel free to keep it narrowly trained. It will have to be pruned annually to keep its shape.
David
Javad
March 28, 2021Hi, I have a small garden in which I have planted a number of 2-year-old almond seedlings, but it has not bloomed since a week has passed since spring. What is the reason? Thank you very much.
David Doll
April 3, 2021Javad,
If they trees were just planted, they probably havent developed fruit bud. Give them a year or two to see if fruit buds develop.
David
Gary
December 16, 2021Hi David. We have an orchard with 4th to 5th leaf Independence Almonds. These trees were never clipped when planted, and have never been pruned. They are healthy, but there is no light interception through the canopy with all the uprights. Can the central leader be cut out to open it up? I do not want to cut too much so that yields drop. I do realize the non productive shoot growth that will occur.
Davidd
January 9, 2022Gary,
This is a complicated situation. If too much wood is removed, the tree will push new vertical shoots. The best thing to do is slowly remove limbs over a few years to bring the tree to the structure you want. Essentially, you wan to clean up the center of the tree without exposing too much light at a given point. To do this, I would remove more than 1-3 of the upright limbs. I have done something similar in an orchard on a P/A hybrid rootstock. We set a rule of 1-2 cuts per tree per year, and the orchard was able to be restructured over a 2-3 year period.
David
Javad
January 9, 2022Hello Dr. David
Thank you for the scientific and useful content you have posted on the site
I planted some almond kernels, now they are two weeks old, they are green and their height is 10 to 15 cm
Can I reduce their height a bit to make the stem thicker?
How can I send photos of some of them?
Javad
January 23, 2022Hello Dr. David
January 9 Regarding the pruning of green almond seedlings from almond kernels, which I planted and cultivated myself and they are about 30 months old and their height is now 30 to 40 cm, I asked for forgiveness. I am very excited. This is my first experience.
Can I send their photos to your email?
Javad
January 23, 2022Hi doctor, there seems to be a mistake in the translation. Their age is 30 days from the time they germinate and come out of the soil.
Amanda Dowd
January 20, 2023Great article, thank you. Have a very old almond tree that was hedge a few times and is now towering with vertical limbs. Seems the best now is to carefully thin it out and otherwise let it be. It is a marvel of a feast for pollinators in March.
Davidd
February 12, 2023You got it! Cutting too much at one time will result in the same vertical growth. Thinning must occur over a period of years.