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HOW TO PRUNE A PLUM TREE
Looking after a plum tree is principally a once a year task of pruning it. If pruning is done correctly, and it's not complicated, then they are unlikely to suffer from many problems.
There are three forms of plum tree, the most common is the bush form, the less common are pyramid and standard forms.
Occasionally people grow plum trees in a fan form against a wall.
This article deals with pruning a bush shaped plum tree, by far the most common. It answers the common questions of when to prune, how to prune and also explains how to tackle older more overgrown plum trees.
Plum trees differ from most other fruit trees because they should only be pruned when they are in full growth. In the UK, the best time to prune your plum tree is in mid June 2017, never in winter when they are dormant. The reason is that pruning your plum tree when it is dormant will expose it to the risk of Silver Leaf disease and other fungal infections.
Strongly growing plum trees are more resistant fungal infections. It's also the case that Silver Leaf Disease spreads through spores which are far more common in the damp conditions which exist in autumn and winter.
In general any time from late spring to the end of July is the risk free time to prune your plum tree.
There are two exceptions to this rule (there is always an exception or two!) and they are:
- A newly bought one year old plum tree planted in winter. The supplier of a new plum tree should
have identified if they have sold you a one or a two year old plum tree. If not see the two
diagrams lower down this article to help you identify what age your tree is.
It is important to prune a one year plum tree as soon as possible to help it establish a good structure. At the same time, pruning in winter exposes the tree to fungal infections. With these two factors in mind we recommend pruning a one year old tree in early March (late March in cold areas of the UK).
Prune on a dry day and use a sharp pair of secateurs. Make the cut a sloping one to avoid water settling on the cut surface. See pruning a one year tree below for more details.
- Where an established plum tree suffers breakages of one or more branches (wind and weight of
fruit are two common reasons) then it is best to prune back the broken branch to good solid wood
immediately. The tree will suffer less if a branch has been cleanly cut compared to a breakage
where the surface of the broken branch is open and ragged.
Prune on a dry day and use sharp secateurs / pruning knives.
HOW TO PRUNE YOUR PLUM TREE
Many books and website articles over-complicate the task of pruning plum trees but in truth they are far more tolerant of incorrect pruning compared to apple and pear trees. The basic principles to adhere to are to prune once a year at the time given above and to prune them to a wine goblet shape with the centre of the tree relatively free from branches and foliage.
The "wine goblet" principle of pruning encourages the branches to grow up and away from the centre of the tree. The majority of shoots growing into the centre of the tree are pruned away completely and those growing outwards are hard pruned to encourage more growth this and next year.
The picture above is our graphically challenged attempt at explaining the idea behind pruning a plum tree to a wine goblet shape. In an ideal world your plum tree should end up with three or four main branches growing from the main trunk of the tree.
The diagram shows only two of the main branches coming from the main stem although if you are lucky you might manage all three or four coming from the main stem. In many cases though, only two main branches will come at the correct height. Another main branch should then be left to grow from the original two branches (see branches 3 and 4 in diagram)
It will be impossible to get it exactly accurate, but however many main branches you choose to have, they should be roughly evenly spaced out to give the tree balance.
If you prune your plum tree at the correct time of year (see section above) you will be pruning your plum tree when the fruit has already started to form. This will lead you into the temptation of under-pruning it to avoid cutting off fruit bearing shoots and stems. Avoid the temptation and prune the tree correctly!
Most plum trees form far too much fruit and this can be severe enough to cause the branches to break under the weight, Victoria plum trees are a prime example of this. Correct pruning will indeed remove a few potentially fruit bearing stems but this will only improve the health of the tree and result in larger plums.
One particular plum tree we have reviewed, Cambridge Gage, is slow to establish and we recommend less pruning than recommended below. See the Cambridge Gage tree page here for specific details on pruning this variety.
Pruning in the first and second year of a plum tree's life is easier but slightly different because there are fewer branches to prune. The three diagrams below explain how to prune a plum tree in years one, two and three.
HOW TO PRUNE A ONE YEAR OLD PLUM TREE
Read the above section entitled "How to Prune Your Plum
Tree" above carefully before starting year one pruning. It will help explain
the overall process and aims of pruning your plum tree.
First year pruning is very easy, simply prune back the stem to about 1m / 3ft high in early to late March (see below for why at this time of year). If you are intending to grow your plum tree as a half-standard bush then prune to 1.2m / 4ft or 1.6m / 5ft for a full standard.
You want at least two branches to form from the main stem and these will come from buds clearly visible. So in year one you may want to prune the main stem slightly higher so that a promising bud or two, in the correct position, is left on the main stem.
It is important to prune a one year plum tree as soon as possible to help it establish a good structure. At the same time, pruning in winter exposes the tree to fungal infections. With these two conflicting factors in mind we recommend pruning a one year old tree in mid March (late March in cold areas of the UK).
The supplier of your plum tree will have told you the age of your plum tree when you bought it. If you don't know the age of your tree use the diagram above and below to decide if your new tree is one or two years old.
Prune on a dry day and use a sharp pair of secateurs. Make the cut a sloping one to avoid water settling on the cut surface. Current advice is not to use a pruning sealant on the cut.
So we can get the timings correct for year two and three pruning, let's assume you plant your new,
one year old tree in January 2017 and pruned it for the first time in March 2017. Dates below will be based on this date.
HOW TO PRUNE A TWO YEAR OLD PLUM TREE
This section on pruning a two year old plum tree applies to the following two situations:
- You bought a one year tree in January 2017 and pruned it shortly afterwards in March 2017 (see first year pruning above).
This second year pruning should occur in
mid June 2018.
- You bought and planted a two year old tree in winter (example date January 2017) and wish to prune it for the first time in mid June 2018.
Prune back the main branches to a length of about 30cm / 12in. Prune back any side shoots to a length of 15cm / 6in. Prune weak shoots away completely and trim back any stems which are crossing. Prune on a dry day and use a sharp pair of secateurs. Make the cut a sloping one to avoid water settling on the cut surface.
During the pruning cut the shoots and branches to an outward facing bud to try and achieve the goblet shape with a clutter free central part. If the position of an outward facing bud only occurs further down the stem to be pruned, prune to that point.
HOW TO PRUNE A THREE YEAR OLD PLUM TREE
Using the example dates given in the above two sections this pruning will occur in mid June 2019.
Third year pruning is the same as second year pruning. Prune back the branches to a length of about 35cm / 14in. Prune back any side shoots to a length of 15cm / 6in. Prune weak shoots away completely and trim back any stems which are crossing. Prune on a dry day and use a sharp pair of secateurs. Make the cut a sloping one to avoid water settling on the cut surface.
Cut the shoots and branches to an outward facing bud to try and achieve the goblet shape with a clutter free central part. If the position of an outward facing bud only occurs further down the stem to be pruned, prune to that point. Particular attention should be paid to keeping most of the centre of the plum tree free from branches. This helps the overall health of the tree by allowing free air circulation thus avoiding fungal diseases.
Yellow Mirabelle Plums
PRUNING IN LATER YEARS
Prune the top stems and branches by about a third to keep the plum tree from growing too high. Other stems and branches should be trimmed to maintain an overall goblet shape. Once again, prune away shoots growing into the centre of the tree to keep it relatively open.
PRUNING LARGER NEGLECTED PLUM TREES
Many plum trees are inherited when properties are bought and you may find that they are an overgrown, over-tall tangled mess. Fear not! We have written a web page which shows you exactly how to set about pruning such plum trees to reduce the height, open up the centre of the tree and bring down the level of fruit production so they can be picked without a triple extension ladder. Click here to go to that page now.
Because the best time to prune a plum tree is in the summer many gardeners are concerned that they will need to prune away branches which are bearing fruit. In the majority of cases though this is not really a concern. In years one to three the above recommendations do show significant pruning in order to establish a good basic shape for the future but very few plum trees will produce fruit in their first three years of life so almost no fruit will be pruned away.
In later years we recommend pruning the top growing stems to keep the height within bounds - these top stems will not be bearing fruit, the fruit will be lower down. Some pruning of the lower shoots is recommended to keep the centre of the tree open and if those inward growing stems are bearing fruit then a small number of fruits will indeed be pruned away. However, plum trees do produce lots of fruit and the crop will still be large.
In theory plum trees can be pruned to a cordon shape but in practical terms it's not advisable. To create a cordon shaped fruit tree you need to prune several times a year and also at several points on the stem. Unfortunately plum trees don't respond well to frequent pruning because it significantly increases the risk of introducing infections. This is probably the key reason why you very rarely see cordon plum trees.
FINAL THOUGHTS ON PRUNING PLUM TREES
Don't be panicked by the idea of pruning your plum tree, they are far more tolerant of bad pruning compared to apple or pear trees. Keep the height within bounds, prune away weak shoots, keep the centre reasonably clear and you won't go far wrong.
The tree above is not ideally formed, it has a bias to one side
which makes it slightly unbalanced. But nature has bulked out the
correct branches to make sure the tree remains relatively stable.
And the proof of the pudding is in the eating, this plum tree produces
lots of delicious fruit year after year!
Plum trees require very little care throughout their life (aside from a yearly pruning) but will produce of their best if you thin the fruit, mulch the surrounding ground and give them an annual feed. These are all described in detail below.
Plum trees are well known for producing vast amounts of plums in some years. This is not good for you for two reasons. First, if too many plums are produced, each individual fruit will be small and may well not ripen fully. The second problem with over-production of fruit is that the sheer weight of the fruit can cause branches to break and they don't break cleanly in most cases.
This will ruin the structure of the tree and often leave jagged open wounds which are a source of fungal diseases. Brown Rot is often caused by trees bearing too much fruit which has not been thinned.
Judging how much fruit should be left on your plum tree is really a matter of experience gained over a couple of years, every tree is different. But as a general rule thin young fruits so that at maturity 3cm / 1in will be left between each fruit. The best time to thin plum tree fruit in your area is mid June 2017
One useful tip when thinning plum fruits is to remove more of the fruit which receives less sunshine. In practice, fruits which are nearer the centre of the tree and those which are on the shady side of the tree will ripen slower and should be thinned in preference to those which are likely to receive the most sunshine. Don't go overboard with this principle but bear it in mind.
MULCHING PLUM TREES
Plum trees require a constant source of moisture at their roots especially when the fruits are forming. A mulch with any organic matter around the base of tree each spring will go a long to providing these conditions. If you have no organic material to hand then think again, a mulch of grass cuttings will do the job very well. If you have the money a bag of chipped bark will provide a long-lasting mulch.
A long lasting organic feed such as blood, fish and bone (three handfuls per tree) will provide them with an excellent tonic. It is best applied in spring just before you spread mulch around the trees.
COMMENTS / QUESTIONS LEFT BY OUR READERS
|1 May 2016||From: Najam|
|I have a few years old plum tree in my house when I bought it. Last year it's main branch broke with the weight of its heavy fruit about 1 foot from main stem. Now no branch grows from this broken main branch. Is there anyway to get growth around this area.
ANSWER: When a branch breaks on any fruit tree, new growth will only appear if there are buds on the remaining branch. If there are no buds on the remaining branch, no new growth will appear. There is nothing you can do to encourage new growth on that branch. Over time the tree will attempt to "balance" itself out and new growth will tend to be more vigorous on the side with the broken branch. However, this can take five years or so on an established plum tree to show significant results.
|3 April 2016||From: Joanne|
|I have planted a 2 year old Victoria plum tree this March 2016 do I prune it this June or next June?
ANSWER: This answer applies to all varieties of plum trees newly planted in spring. First, follow the instructions which came with the plum tree at the time of planting. Then prune the next year in June time as described above.
If the tree came with no instructions or they are lost, it's probably best to prune the main stem to 1m / 3ft high but make sure there at least four side branches (or buds) below the pruning point. These side branches / buds will be the main branches for the remainder of the tree's life. If you prune below them further buds may not form on the main stem. If in doubt, don't prune in the first year.
|4 September 2015||From: Lee Williams|
|I have a mature Victoria plum tree sometimes it
crops heavy and the next year it produces very little fruit.
ANSWER: This is a very common problem with many plum trees and Victoria is no exception. It is a natural reaction of the tree. If it crops heavily one year it is quite likely to undercrop the next year. To some degree this can be corrected. When you notice lots of plums forming in a year simply snip 30% of them off. This will have two effects. First it will help the tree to produce a good crop the next year and secondly the crop in the current year will tend to produce larger plums.
The reasons for this are not fully understood but it seems to be in-built into plum trees in particular. Fruit trees are wise old things and they know how to survive in the wild. A slight intervention as suggested above helps to "domesticate" them!
|26 July 2015||From: Tony Ford|
|I have inherited a tree about 30 foot tall. It has red leaves. I did not realise it was a plum tree until it produced sparse small red plumbs. It is about 2ft 6 wide at the base and the lowest branches are 6 foot off the ground. I don't where where to begin, it is a beautiful looking tree but very neglected.
ANSWER: At 30 foot tall there is really nothing an amateur gardener can do. Any pruning needs to be left to an expert with the correct climbing and cutting equipment. If you do intend to get an expert in I would take some photographs of the whole and cut fruit now.
The tree you describe, if it is indeed a plum tree, is not common so identification of the fruit would be key. It may also not be plum tree, it could be a damson or something else. If it were a damson tree the pruning could be far more harsh (and rewarding) than pruning a normal plum tree. Do not prune plum trees in winter, the risk of fungal infection is too high.
|4 July 2015||From: John A|
|My plum tree is 5 years old plenty of fruit on developing nicely, but getting new growth on all the branches. Can I prune this new growth now 04/07?
ANSWER: Yes, it's fine to prune a plum tree in July. Ideally early spring to early summer is best but up to mid / end July poses little risk. Prune in August onwards and the risk of fungal infections increases significantly. To further reduce the risk prune on a dry sunny day.
|27 June 2015||From: Josh|
|Hello, last year my nan got her plum tree chopped half its length, and we began to grow it as a hedge, but realised that this was wrong and this year there was no flowering, but mid June this year i thinned it all out and the branches have become thicker, will it blossom next year and fruit or is it lost? Also, it normally bears small yellow plums, and my nan doesn't know what it is called, do you have any ideas?
ANSWER: All is definitely not lost! After a severe pruning a plum tree can take a couple of years to start producing fruit again. So continue looking after it and you should have plums again in a couple of years.
The variety may be a Mirabelle, click here for a picture and description
|22 June 2015||From: Tim Fortune|
|I bought a czar plum tree 3 years ago and it has grown well but not blossomed or fruited at all. Why?
ANSWER: Three to four years iss about average for a Czar plum tree to produce fruit so give it another year or two and you will be having plums for the next 30 to 40 years. Czar reaches full plum production after about six years.
|21 June 2015||From: Diane|
|Do plums fruit on new shoots and when pruning plum tree should you touch any of the new growth? Thanks.
ANSWER: Normally plums fruit on wood which is two to three years old or older. They do not fruit on shoots grown this season.
In the first three years (as described in the main article above) growth of new main shoots should be pruned back by about 60% of their length and some of that will be the current year's growth. On an established tree, new growth will also be pruned especially to keep the centre of the tree open.
|17 June 2015||From: Celine|
|I have a two year old greengage tree that has grown with a u giving two leaders. should I cut one out?
ANSWER: It really depends on how high the two leaders have split. If they are 1m or so high then leave well alone, just consider them as two separate branches and try and encourage two more main ones to form so the tree is balanced.
If the split occurs below 1m then the problem is that the fruit will hang very low near to the ground and liable to pick up infections etc. They will also require bending down to harvest the fruit. In that case you might want to cut away one of the leaders and encourage branching to occur higher up the tree.
|26 May 2015||From: Celine|
|Thank you for very clear advice on pruning. I have a cherry plum tree and a greengage tree both growing in containers. How do you recommend feeding them (I'm growing them organically)? Many thanks, Celine
ANSWER: Plum trees and greengages are tricky to grow successfully in containers, so good luck with them. As for feeding, blood, fish and bone fertiliser (which is organic) is the best solution. A good handful gently worked into the top soil in April and then again in July is all they need. If you feed them too much they will be very reluctant to produce fruit.
|10 May 2015||From: John Clark|
|Hi, we planted our tree last year and its first pruning will be this June but I don't know how old it is.
It looks like your sketch of the 3 year tree. It's about 6ft high and 5ft wide, 3 branches at 18in from soil,
2 more 3ft from soil then a 'v' of branches to the 6ft height. Quite a few branches are around 2-3ft long.
Do I really cut all these to around 12 inches long as the sketches suggest? Thanks, John
ANSWER: Difficult question to answer because when you say "we planted our tree last year", that could mean January 2014 or December 2014, a difference of nearly a year.
The principle behind pruning in the third year is based on the premise that most plum trees will only produce a useful crop from ages four to five years onwards. The pruning in years one to three is aimed at creating a good structure and also branches which will be strong enough to support the weight of a full crop of plums in later years.
So in summary, if your tree is three years old I would prune it exactly as described in the main article, if it is four years I would prune it as described in the section 'pruning in later years'. I have updated the article to try and make it easier to understand but I think there are no significant differences to the original information.
|11 January 2016||From: Derek Fairfield|
|Have found unwanted DVDs a good deterrent to pigeons and other birds. They do not seem to worry bees etc.|
|04 January 2016||From: Kim Gartmann|
|Hello, I live in the So. of France, it\'s cold here (ca. 5 - 12Â° C) and locals say now is a
good time to prune plum trees, however various sites incl. yours suggest June? We have 1 very old and 4 - 5 4 yr. old
(wild) trees, about 2 - 3 m tall, flower in Feb. and produce fruit in June/July. BTW, like your wine glass form pruning
suggestion and want to contain the trees before they get totally out of control. Pls. advise.
FROM DAVE: The locals are wrong. Correct for apple and pear trees but definitely NOT plum trees. Do not prune plum trees in the middle of winter, you risk infection especially of Silver Leaf disease. Prune when the tree is growing strongly, May / June is a good time. That applies to your area of France as well as the UK.
|02 September 14||From: Margaret|
|Dave this website is fantastic.
FROM DAVE: Thanks, glad it's of use
|01 September 14||From: Lucy|
We have a very old neglected 10 year old plum tree. It produces masses of tasty plums. But unfortunately the wasps always beat us to them, and lots that we pick have maggots/ grubs inside which has completely put us off!! Any advice ??
FROM DAVE: Yes, have a look at our page dedicated to plum tree pests and diseases. The most likely causes are Plum Sawfly or Plum Moth both of which are described in detail on that page. As far as wasps are concerned I know of no solution because setting sugary traps in jam jars just seems to attract more wasps. I will be investigating this in more detail over the next few months and will post what I find on the pests and disease page above. There is a product called the Waspinator but I have not tested it yet.
|31 August 14||From: Pauline Logan|
|I have an 18 year old plum tree which produced 2 tiny plums last year for the first time. Was looking forward to some fruit this year - but nothing!! Can you help? Very informative page. Thank you.
FROM DAVE: Hi Pauline, plum trees are notorious for producing fruit one year and then missing a couple. You don't say how it has cropped over the past five years or so. Also, how tall has the tree grown which may give some indication of the rootstock its on.
|22 August 14||From: j. graham|
|I finally found your page on the internet and I found it to be very informative, answering all my queries on Victoria plum trees. Thank you so much.
FROM DAVE: Thanks, glad you've found it useful.
|08 August 14||From: Andy|
|Can I prune my tree in August after it's fruited it's in a fan shape?
FROM DAVE: It's possible to prune a plum tree at any time of year but from the beginning of August onwards the risk of fungal infections getting into pruning wounds increases. It's up to you to determine how much risk you want to take. Minor pruning now should be OK but anything significant poses a risk.
|04 August 14||From: Patrick|
|Hi Dave. We have a 2 year old Victoria Plum tree that bore a great deal of good fruit in year 1, which was a big surprise. This year it has only produced 3 plums but otherwise looks healthy. We need to give it a trim next June as per your advice. We missed this year. Any reason to panic yet?
FROM DAVE: That's absolutely normal Patrick, in fact the unusual feature is getting fruit in the first year! Now that is unusual. Three years or so until the tree produces fruits is about normal for a Victoria.
|30 July 14||From: Colin|
|Can you prune a plum as a cordon tree?
FROM DAVE: The basic advice is that it is possible but not practical. See our new section on your question here.
|23 June 14||From: Doug Doran|
|My six/seven year old Victoria Plum tree is bearing fruit, some of which look scabby, but very many of the leaves are curling up and withering. See attached picture (click here). Is this terminal or just a bad case of Plum Leaf Curl Aphids.
FROM DAVE: To diagnose Plum Leaf Curl check the leaves for signs of aphids and / or the white skins they shed. Sometimes they are not particularly visible to the naked eye so use a magnifying glass or take a digital picture of a single leaf and look at it in full size. Those two methods may show up aphids that normal viewing misses. Having done that, if there are no signs of aphids then the problem is elsewhere.
Plum trees are notorious for looking not so good one year but then recovering the next year. On that basis I would never diagnose the problem as terminal until two years have passed. If there are no aphids, has the ground been water-logged? It was a very wet winter / spring and plum trees do not like water-logged soil at all.
I can’t see the whole tree from the picture but it does appear that the branches are very long, with some unusual, almost right angled, bends in them, presumably as a result of some harsh pruning a couple of years ago or broken branches? I think the tree would benefit from some pruning to help it produce leaves and fruit earlier down the branches. My website will be updated to include how to do this but it’s not there at the moment. However, this video from Stephen Hayes (see link below) is excellent. He is very practical and willing to explain the realities of pruning plum trees. Take a look and decide how to proceed from there on. To add my own little bit of advice, I would spread the pruning out over two years rather than one and I would also try and shorten those branches which have the right angled bends in them to end up with straighter branches.
See the video here.
|13 June '14||From: Hilier Ward|
|I planted a Victoria plum tree last year and there are some green fruit on the tree.
Most of the leaves have gone brown and curled up. What's wrong with it. Do I prune it before the fruit matures as above (July) thanks
FROM DAVE: That sounds like two questions. First, do prune in July time, see the question and answer below if you are concerned that you may be pruning away fruit. Second, it does sound like you have a pest problem and it it is probably Plum Leaf Curl Aphids, click here for more details of this pest and how to treat it. If you send a picture to our email address I can diagnose it more definitely.
|August '14||From: Lots of people|
|Lots of people are asking can prune they their plum tree
in August. My advice is don't do it for two reasons. First you open up
the tree to fungal and bacterial infections. The best time for pruning to avoid
this danger is in early summer. Late May to early July.
The second reason is that significant pruning in August and September will, as always, result in leaf loss which will not have time to be replaced. This means the tree does not get the opportunity to absorb nutrients from the leaves before they fall off in autumn.
|01 June '14||From: Harry|
|I have a plum tree which is now in its third year my question is
will it flower to produce the fruit first and if so when does this happen and what time of the year.
FROM DAVE: Yes, the tree must produce flowers before it can produce fruit. The flowers are pollinated by insects and only after a flower has been pollinated can it produce fruit. Varieties differ and flowering times are dependent on where you live but in general the end of April is the average time for flower production on plum trees. With a bit of luck it should produce flowers and fruit next year.
|01 June '14||From: Sue Green|
|Hi I have a plum tree that has been In for two years now and has never flower or had any fruit on it. I feed it and make sure it has a lot of water so can you tell me what I am doing wrong kind regards sue green.
FROM DAVE: The average time for a plum tree to start producing fruit is about four years. Some varieties produce fruit earlier or later than the average. So your two year old plum tree probably has no problem at all, just wait a year or two. Good luck.
|25 May '14||From: Sally|
|Thank you my tree is at least 10 years old and has not had any pruning so i need to give it a really good one.|
|10 May '14||From: Diane|
|Are pigeons likely to be eating my Victoria plum tree? Last year and this, the three year old tree started off well then, within a couple of days almost all the leaves were ripped to shreds and the twiggier branches snapped off. I have not seen pigeons doing this but last year witnessed them ripping up a Forsythia which is about eight feet away. No fruit developed last year and looking the same sad way this. Help!
ANSWER FROM DAVE: The simple answer unfortunately is yes. This problem is not uncommon. I've updated our plum pest and disease page with lots more detail about this problem and how to cope with it.
|24 April '14||From: Babru|
|Excellent article, informative and well laid out page|
|12 April '14||From: Judy|
|I have inherited an old plum tree with my recent house purchase and need to remove a three inch diameter lower branch. When is the correct time of year to do it and do I need to seal the cut afterwards? If so with what?
Hope you can help.
ANSWER FROM DAVE: Plum trees should be pruned when they are growing vigorously, June is a good time in the UK. The jury is still out about using sealants. My personal opinion is not to use them, let the tree heal itself. But I definitely would prune on a dry day to reduce the risk of any fungal infections.