Our Belgian fence espalier of apples, pears, and nashi trees is a highlight of the blended edible and aesthetic double-duty design in our garden. It’s also been the sticky tricky point of some of our big lessons learned and hard garden losses during its establishment. Here’s how to plan, plant, and care for a Belgian fence espalier of fruit trees trained into a carefully calculated diamond pattern. And some mistakes we made, so that hopefully you don’t suffer the same.
Espalier as a Garden Element
Espalier is the artful garden practice of training, shaping, and trimming trees and other plants to control growth and structure. It can be used create purposeful forms, enhance sun exposure, modify productivity, and to fit plants into spaces where they might otherwise not be suitable.
It’s not for the faint of heart, especially if you fear pruning. But, for the brave, it can be a great way to add interest, productivity, and variety to your garden. The right style and shape will depend on a combination of space, design plans, and the growth/fruiting habits of the plant(s) you’d like to include. And, I would argue, how brave you are about taking the plunge into pruning.
A Belgian Fence is one of the more complicated espalier options. Unlike a single-tree structure, it requires very careful planning and spacing. Then it needs training and pruning to create and maintain its shape, and extra attention to care for its tightly planted overlapping trees. But, it is a beautiful way to fit a lot of trees into a smaller space and/or create a living fence or screen.
Belgian Fence Espalier (Diamond Pattern)
Pattern
The diamond patterned Belgian fence espalier grows a line of evenly spaced closely planted trees, trained and trimmed into overlapping V-shapes. Or Y-shapes, if you include the base trunk. It’s narrow but dense form is well-suited for walls, but also for creating stunning living fences, barriers, borders, and screens. The more space you have, the more trees you can line up to let the continuous diamond pattern really deliver on its wow-factor potential.
Our Belgian fence is grown as a free-standing island screen of fruit trees, offset from the nearby side-boundary of our property for access and sunlight exposure. It’s positioned between the boundary fence and a large living room window, creating a focal point and a much nicer view than a plain fence or the side of our neighbours’ house/roof.
Productivity
The V-shape means that each tree gets two permanent diagonal branches, other than any variations at the ends of the rows. Because this is an old-growth structure, it’s best suited for ornamentals or spur-bearing fruit trees that produce on old wood rather than new growth or tips.
Potential Problems
The Belgian fence will need support during establishment and potentially longer term, especially if it’s free-standing without a wall for support or storm buffering. The branches are trained to cross each other, which creates potential points for friction and makes it easier for diseases or pests to transfer between the different trees. As a multi-tree pattern, it requires multiple expensive young trees and it can be tricky if one or more of those ever need to be replaced later.
Tricky Ends
As a continuous pattern, the ends can also be problematic. For a large fence or border, you could bracket the ends with full trees or another natural hard stop. For a full design or in freestanding feature, altering the trimming and training of end trees to fill out the missing parts makes a more eye-pleasing option (see the diagrams later in the post for examples).
Selecting Trees for a Belgian Fence Espalier
If you’re planting for looks, anything that can handle the close neighbours and had pruning could work. But if you’re keen to have an edible espalier, spur-bearing apples and/or pears are good fruit tree options for a Belgian fence. Individually, the trees will never be anywhere as productive as allowing a tree to grow freely and fully. But a row of espalier trees can still offer up a lot of fruit, especially if you’re just planting for your household needs. Bonus for variety and stagger.
If looks are important, a single variety will be the most uniform option for growth habit and looks. But, if you’re keen to balance looks with productivity, you can compromise. Mixing different tree-types won’t look quite the same, but they can still look similar enough for a great espalier. Don’t forget about your cross-pollinator needs and compatible pollinator combinations.
Our Belgian fence espalier combines different varieties of apples, pears, and nashi (Asian pear). There are obvious differences in the bark, leaf, flowers, fruit, as well as seasonal changes. Not enought to wreck the cohesion and care, though. And it creates a long varied harvest for fruit.
Select carefully, espalier planners. Not all apple or pear trees will be suitable for fruiting or planting in your Belgian fence. Make sure you’re selecting spur-bearing varieties and that your plans cover compatible pollinating or cross-pollinating. And when you head out shopping, also ensure that your root stocks are suitable for conditions and try and keep those similar too, where feasible, so that growth and competition in your tight line of trees stays relatively even.
Planning and Calculating Your Belgian Fence Design
Tight Squeezes
The tighter your tree plantings are together, the tighter the diamonds will be in the mature fence. A tight pattern lets you squeeze more trees into the row, but might also make your trees crankier than if they had a bit more room and we’re competing so closely for soil/nutrients. More care will be needed to try and keep them happy and healthy.
Tighter diamonds also need extra pruning to keep the pattern visible. Even with pruning, the diamond pattern might not be clear during periods of high growth. Mine gets a bit lost when I’m reluctant to prune away too much of the foliage that’s supporting developing fruit (more below).
Don’t forget that your trunks and branches will also thicken up as the trees mature. This growth and expansion in girth will slowly consume some of the open space within your pattern, too.
Important Planning Measurements
- Planned Row Length = The total length of your planned Belgian fence from end to end.
- Planned Mature Height = The mature height for your Belgian fence, vertical from soil level.
- Planned Pattern Height = The mature height, as above, minus a provision for the base trunks below the branches of your V pattern. The starting point for your pattern depends on your personal preferences for design and looks, but it must always be above your grafts.
Single Diamond Belgian Fences
Let’s look at the single diamond pattern first. Once you wrap your head around that pattern and math, it becomes much easier to expand the concepts into double or multiple diamond patterns. Those are the more commonly seen structures for Belgian fence espaliers.
In a single diamond pattern, all trees equally spaced. From just below the cut point of the base trunk, one branch is trained from the left and one branch from the right, on angles to form a V-shape. The V-shapes overlap with neighbouring V-shapes to create a row of single diamonds.
With the exception of modifications for trees and branches at row ends, each branch:
- Starts from the base trunk (bottom point for diamond) and is trained sideways on a diagonal, so that the branch tip ends above the neighbouring tree’s trunk.
- Crosses the nearest neighbour (shared side point for diamonds), then
- Meets the next neighbour’s branch (top for neighbouring diamond).
The diamonds will always be the width of the tree spacing, but the height can be varied by adjusting the angle of the Vs. For 45 degree angles, the tree spacing and pattern height are equal, making each diamond an even rotated square. For other angles, the diamonds will be elongated. This can be useful for design, squeezing extra trees into a set length/height, or just as a subtle tweak to round the total number of trees in your espalier to a preferred number.
Calculations and Configurations
Use the planned row length with the information above to determine the number of trees required for your design. Remember to add an extra tree for the “zero” end of your espalier, if applicable. If you don’t care about angles or if the height is flexible, then it’s even easier.
Example Configurations:
Here are some examples of variations for a pretend espalier with a set 2m planned mature height (with 0.5m for trunk, 1.5m for planned pattern height) and a planned total row length of 12m:
- Priority: Even Single Diamonds. 12/1.5=8, so a 12m row would require 8(+1) trees if planted evenly with the planned pattern height at 1.5m spacings. In this configuration, the branches for the espalier will be trained on 45 degree angles for even square diamonds.
- Priority: Set Tree Spacing. The espalier needs to have 1m spacings, if possible. 12/1=12, so a 12m row would require 12(+1) trees if planted at 1m spacings. These will be trained on sharper angles, creating a tighter row of elongated diamonds.
- Priority: Set Number of Trees. The plan needs to have 10 trees if possible. So we start with 10-1 = 9 to make sure we don’t forget about our zero starter tree, and then calculate 12/9 = 1.33m as approximate spacings for planting
- Priority: Screening/Fencing or Maximising Planting. Consider changing the planned pattern from single diamonds to a planned pattern double or multiple diamonds (see below) so that you can have offset rows of smaller diamonds on closely planted trunks.
Double or Multiple Diamond Belgian Fences
Don’t worry, this is easier than you might think after the geometry above. It’s the classic pattern for a Belgian fence for the trees to be planted closely together and to form multiple diamonds.
To go from a single diamond pattern to a double diamond or multiple diamond, you just stack more cross-overs before the branch tips reach your final mature height, if you have a fixed height for your espalier. If you don’t have a fixed height, they can just keep on growing and stacking until they eventually max out. Or you get annoyed by the scruffy tops and set a height. Hehehe.
Once again, all trees equally spaced. From just below the cut point of the base trunk, one branch is trained from the left and one branch is trained from the right, on angles to form a V-shape. The V-shapes overlap with neighbouring V-shapes to create offset rows of diamonds.
With the exception of modifications for trees and branches at row ends, each branch:
- Starts from the base trunk (bottom point for diamond) and is trained sideways on a diagonal, so that the branch tip eventually ends above a neighbouring tree’s trunk. How far away that neighbour is will be the multiplier for your stacks.
- Crosses the nearest neighbour (shared side point for diamonds), then
- Meets the next neighbour’s branch (top for neighbouring diamond), and
- Repeats those cross-over diamond corners until finally hitting end height (top for the final diamond, if the espalier is formally shaped and topped).
As with singles, the diamonds will always be the width of the tree spacing, but the height can be varied by adjusting the angle of the Vs. For 45 degree angles, the tree spacing and pattern height are equal, making each diamond an even rotated square. For other angles, the diamonds will be elongated. As with singles, this can be useful for design, squeezing in extra trees, or as a subtle tweak to round the total number of trees in your espalier to a whole or preferred number.
Purchasing and Planting Your Trees
Selecting Whips for a Belgian Fence Espalier
Ideally, you’re going to be looking for young healthy whips of similar calliper (trunk thickeness diameter) and condition, of the vatiety or varieties you’d like to plant in your espalier. These will be year-old grafted trees on suitable and compatible rootstocks, as noted above.
You’ll want to make sure that your grafts aren’t too high, so that the grafting point on each tree is well below the point where you’ll be cutting the base trunk to branch out into your V. If you’re ordering rather than selecting in person, you might need to add this as a special request for the nursery or supplier to avoid getting something unsuitable (one of my lessons learned).
Bigger isn’t better for starting off your Belgian fence. The larger the calliper of the trunk, the more obvious the cut point will be until the tree, ideally, heals and conceals. If your tree is thick, either at the time of purchase and planting, or because you delayed cutting after planting (another of my lessons learned) the V junctions might not look as nice as a smaller calliper.
Checking Your Whips for Best Planting Positions
Position your whips carefully while you’re preparing to planting out your Belgin fence. In addition to following your planting plans on spacing and which variety goes where, you’ll want to take a close look at the trunk of each whip before you plant it. Never cut below your graft, and make sure you leave a decent section of main trunk above the graft. You don’t want to grow your branches from the rootstock instead of your desired grafted tree.
If the whip has existing branches or visible bud points in ideal places for your V branches, position the tree when planting so you’ll be able take advantage of those. If it has a really ugly graft or a “bad side”, you might be able to position that to the back or in another less visible manner, depending on your design and layout.
Planting Your Whips
Ideally, planting the new fruit trees for the espalier happens in winter dormancy here in New Zealand, or in shoulder season dormancy for areas with harsher winters. Planting a few weeks before the tree will naturally break dormancy is a good time. Spring vigor is good for new growth, and we’re going to be cutting the trees to send out new branches to start our V shapes.
Prepare your soil and plant your whips just like you would any other young tree, just with a lot more care on position and placement. Check and double check your measurements, and consider making yourself a little spacer template to simplify positioning your holes and checking your trunk-to-trunk tree spacings. Even planting spacing will set you up for success.
Unless your whips came with ideal branches, you won’t need to have your espalier wires and supports in place at this stage. But you should have any invasive hardscaping and digging done before your trees go in so there’s no risk of accidently damaging your trees or their roots later.
Our garden has heavy clay soil, so we built slightly raised beds and put our supports in at the same time. The tree roots will spread out well below the bed, but it gives them a shallow buffer against winter soggy soil, and makes it easy to mow and trim around them. And the dogs have decided that it’s the centre of a hippodrome for racing and play, which is a hilarious bonus.
Companion Plants, Groundcovers, and Mulches
When the espalier is first planted and cut, it’s going to look pretty sparse until things start to grow. If you decide to underplant or companion plant, choose something that won’t compete too heavily with the new tree roots as they establish. Later, you can switch things up if you’d like.
We had annual flowers and mulch for the first couple of years. Currently, we have chocolate mint. Some say mint helps keep pests away, including codling moth, so I decided to give it a shot. Beware though. Once mint is planted in the ground, you’ll never be rid of it.
I couldn’t source a low mint, like Corsican, so I planted chocolate. It acts as a living groundcover instead fo mulch in summer, but it’s semi-dormant in our winters, so it’s easy to clean-up and top-dress the beds. I cut it back repeatedly during the growing season to help keep it from getting too leggy or rusty. Elsewhere, thyme and strawberries are my go-tos under our fruit trees.
Pruning and Starting Your Espalier Pattern
Don’t Delay Necessary Cuts
Don’t be like me and let your whips settle in for a while before you cut. As noted above, time to grow bigger calliper trunks can lead to ugly junctions or wounds that don’t healthily heal. Another of my lessons learned, and perhaps my biggest regret from starting the espalier. A mistake that I didn’t repeat when we had to replace a tree several years later due to its health.
Cutting the Trunks for the Starting V
Cut all of your trunks on a consistent height and angle, allowing a few centimetres above the ideal starting point for your V branches. Front-to-back slopes may be more visually pleasing, depending on your design and placement. Clean your tools carefully between cuts.
A possible exception, depending on your design, will be the ends of your espalier. You might decide to cut for consistency, keep the whips as uprights, or do something else these trees.
Setting Up Your Supports
Before you start training, I recommend putting a temporary hard support frame into place for the young supple branches. If you have a permanent support structure and wires in place, you can use these to anchor temporary framing.
We started with training on a string pattern tied from the wires, but it wasn’t sturdy enough to hold the new growth straight (another lesson). Bamboo poles or coated stakes work really well, and can be easily anchored at angles between the soil and the more permanent espalier wires.
Planting distance sets the training shape, as the branches need to cross and meet on pattern. You don’t need to measure or check angles when you set up your framing or while training. Just make sure the cross/end points are all at the right places relative to the tree trunks. Easy as.
Establishing the Base Diamond Pattern
As spring rolls around and the trees start to wake up, your branches and/or buds for branches will wake up too. Keep a close eye on your trunks at this stage, so you can remove unwanted buds/branches and keep the tree focused on growth you might want to keep for your V.
Once the tree starts to branch out, don’t wait too long to start formal training. Point the chosen stems in the right direction and start securing them towards or onto your frame. The young growth will be flexible, so we want to train it and keep our V shapely and straight. Unlike my wiggly errors with string before switching to bamboo, as noted above. Don’t be like me…
Keep on tying it incrementally, making sure your ties are secure but loose enough to allow the stem to continue growing. Check your existing ties regularly, and remove and replace ties if they start to get tight. You don’t want to accidently torniquet off your developing branch.
Once the growth reaches the top of your fence and hardens, you can remove the temporary frames and secure your branches to the wires to help hold shape and for support against strong winds. This might take more than one season. You might need to remove side shoots, flower buds, fruit, etc. from the young branches during this stage. More on general pruning below.
Pruning and Maintaining Your Espalier Pattern
Espalier takes constant effort to maintain form, even after the base structure is established. Your trees will keep trying to pop out new branches and pruning is the only want to keep that growth from swallowing the Belgian fence pattern back into a next of branchy leafy chaos. The smaller the diamonds, the more work (and sacrifice) is needed to maintain a clear crisp pattern.
Espalier is an art for pruning rule breakers, at least if you want to keep your shapes clear. Unlike the traditional seasonal or dormancy pruning “rules”, espalier structure and clarity benefits from constant tweaking and/or summer pruning. But this comes with risks and compromises.
Pruning cuts are an avenue for disease to enter your trees. Always prune in suitable dry weather using sharp clean tools. Sanitise your tools as you change branches (ideal) or trees (recommended) to limit the accidental spread of any nasties between your trees or their branches. Unlike a full tree where you could cut away a diseased branch without too much concern, each tree in our Belgian fence only has two branches. (other than the ends or other special modifications). Losing a branch or a tree from your espalier is a major loss.
On spur-bearing fruit trees, pruning the spurs too short or completely off will reduce or eliminate fruit production. But sometimes you might need or want to do a hard prune or remove spurs due to location, age, overcrowding, general health, or just to clean back your espalier pattern.
Tree Care in a Belgian Fence Espalier
Pruning isn’t the only higher maintenance aspect of this style of espalier. Tightly planted trees, like a Belgian fence, will be competing for water and nutrients in shared soil. They may need more frequent feeding than stand-alone specimens and, in dry weather, watering.
Their overlapping structure also places them at a higher risk of friction damage and makes it easier for pests or diseases to move between neighbours. You’ll want to be on top of all your preventative care and, if applied, seasonal spraying and extra vigilant in checking for problems.
Feature vs. Fruit
If your Belgian fence espalier is planted with edibles and you want to actually harvest the fruit, you’ll probably have a few extra compromises to consider. I let our trees get a little “fluffier” during the growing season to help fuel production, then prune them back into shape later.
Netting for birds is not the most attractive option for your garden features. Espaliers like this are actually easy to cover compared to full tress, but I don’t want to stare at a wall of net all summer and into autumn either. So, our compromise is that we individually bag some fruit to help keep them safe from birds and other pests. Totally personal choice, of course.
We’ll update this post with any major changes, but keep an eye on our social media and you’ll get see our espalier ageing. I’ll try to get some more photos in spring, too. All of my file photos during establishment seem to be on angles, but the spacing between the house, espalier, and fence makes it a bit tricky for direct photos unless taken from indoors looking out.
