I planted my orchard in three phases.  In the spring of 2014, I planted 14 apple trees and 4 pear trees in a 3 by 6 matrix to be trained to wires in the style of espalier.  In the spring of 2015, I added 6 apple trees to one end of the orchard and 4 apple trees to the other end.  These trees are also trained to wires.  In the spring of 2017, I added three more apple trees in a different location, but close enough to allow bees to visit all the trees.  This means that I planted a total of 31 trees.  As of spring 2020, I have replanted 10 of those 31 trees.  Most of those 10 trees were lost to deer and rabbit damage, and one could argue that that is my fault.  I have learned a lot about protecting the trees over the last 6 years that would have been nice to know at the beginning.  A couple of trees just up and died for no apparent reason.  Oh well.

 

The bulk of what follows covers the original 18 trees and was written 5 years ago for a class that I taught.

It has been lightly edited to bring it up to date.

 

A properly pruned apple tree should maximize the amount of sunlight that reaches every fruit-bearing branch in the tree all the way to the center of the tree.   Note that horizontal branches bear the most fruit; diagonal branches will bear some fruit; and vertical branches bear little to no fruit.  The primary purpose of pruning is to strip out the vertical branches and provide the best shape of the remaining horizontal branches.

In contrast, a horizontal cordon espalier tree eliminates all growth except the central trunk and horizontal fruit-bearing branches.  There is no unnecessary growth which consumes water and nutrients at the expense of fruit-bearing branches.  Every branch gets optimum exposure to sunlight resulting in larger, healthier, and more-evenly ripened fruit.  All the fruit is easily accessible, so there is no clawing your way through branches and limbs to pick the fruit.

Espalier training also provides more freedom in deciding where to plant trees in a confined space.  Normally when planning the layout of an orchard, the first question is to determine which direction the rows of trees should go.  In large commercial orchards, the rows typically run north and south. So, the fruit on the east or the west gets half a day’s worth of sunlight.  On the south, the fruit gets a full day’s sunlight.  On the north, the fruit gets no direct sunlight unless the tree has been properly pruned to let sunlight pass into the interior of the tree.  When the trees run east-west, then only the south will get full sunlight unless the trees are adequately spaced apart.  In reality, the rows can be lined up any direction so long as appropriate spacing between trees is maintained (both within rows and between rows) and the trees are properly pruned.

With espaliered trees, the issue is nearly moot so long as the appropriate row spacing is used so that the top of one espaliered tree does not cast shade on the lower cordons of the next row of trees.  Note that when planting espaliered trees against walls, the rows must run mostly east-west (i.e., the rows must be on the south facing side of the wall.)

There are three points of interest when laying out the orchard.  The first point is how tall you what the espaliered tree to be.  This drives the second point which is how far you want the rows to be spaced apart.  The third part is how far the trees should be spaced apart within the row.  All of these points are influenced by how big the tree wants to get on its own. You can mercilessly prune a full-sized tree down to a small espaliered tree if you want to spend all summer doing it.  But generally speaking, the modern orchardist can select from a variety of rootstocks that will limit the growth of the tree.

In my case, the majority of the apple trees were grafted onto MM.111 rootstock which is called semi-dwarf (or sometimes called semi-vigorous).  This rootstock produces a tree that is about 80% the size of the tree grown on normal seedling rootstock.  This means that my trees will be really quite vigorous for an espaliered training.  So, I need to make sure the tree has plenty of room to grow.  Since I don’t want the tree to grow taller than 6 ft or so, this means I need to let the tree grow fairly wide.  Most authorities recommend planting the trees on 6- to 8-foot centers within the row.  I will be planting on 10 ft centers.  {we’ll come back to this topic later}  

Now that we know the espaliers will be 6 ft tall, and the trees will be planted on 10 ft centers, the last remaining point is to determine row spacing.  I will be planting my row running east to west along the southern face of a wooden fence that also runs east-west.

The top cordon of one tree should not cast a shadow over the lower cordons of the trees the row farther from the sun (rows to the north).  The distance of the shadow from the tree casting the shadow is determine by the angle of the sun from the horizon (or from vertical, take your pick).  The trees start to leaf out in April, and the leaves remain on the trees until well into late October to early November.  Given the latitude of my house, we can calculate the angle of the sun throughout the year.

Using an online solar angle calculator, the sun is 24° from vertical (low in the sky) on the shortest day of the year in December.  The sun is 72° from vertical (high in the sky) on the longest day of the year in June.  For bud break in April, the sun is 56° from vertical, and for leaf drop in November, the sun is 32° from vertical.

So, we do a little trigonometry (hell, I’m an engineer) to calculate the angle of projection from the top of one row the bottom of the next.  The wider the row spacing, the lower in the sky the sun can be before one row will cast a shadow on the foot of the row behind it.  I was most interest in 6 ft, 7 ft, or 8 ft row spacing:

  • At 6 ft spacing one row of trees will begin to shade the next row starting in late September which is when many varieties need full sunlight to finish ripening.
  • At 7 ft spacing one row of trees will begin to shade the next row starting in mid October when the latest harvesting apples are being picked.
  • At 8 ft spacing one row of trees will begin to shade the next row starting in late October to early November when all the apples should have been picked.

So, 8 ft spacing it is.  The final layout of the orchard then is three rows of 6 trees in each row.  The trees are planted on 10 ft centers within each row.  The rows are planted 8 ft on center from each other.  And the highest cordon will be set at about 6 ft from the ground.

The distance between the cordons is driven by the nature of the tree being espaliered and the intended pruning practices for the tree.  Cordon spacing can range from 12 to 24 inches.

The cordons should be spaced far enough apart so that one can see through the tree to the wall or landscape behind the tree.  This ensures each branch gets maximum exposure to the sun.

I have chosen to work with 4 cordons.  The first is 22 inches from the ground, and the remaining wires are separated by 18 inches.  Thus, the wires are at 22”, 40”, 58”, and 76” from the ground.  The top wire is slightly above the desired height of 6 ft (72”), but the fruit should still be reachable with both feet on the ground.

The following pictures show the progression of my orchard from installing posts for the trellis system to the end of the first growing season.

 

Laying out the orchard and installing posts for the trellis system in the fall of 2013.

Wires were strung a month later on a cold late November afternoon.

 

Digging holes for all the trees before the shipment arrived from California.

 

Planting all the trees in one day.  The trees arrive with bare roots.

They are wrapped in damp paper or sawdust, which will protect them during shipping.

But they need to be planted ASAP.

 

A month later, mulch has been spread around the trees.

The trees are leafing out, and I begin tying the central leader and branches to wires.

 

The trees are showing the proper shape (mostly) by the end of the 1st growing season.

 

So where are we now 6 years later.

Fifteen of the original 18 trees are still in the ground.  One pear tree died the first year (it happens).  Two were chewed up badly by deer in the 2nd winter.  The deer girdled the tree (removed the bark completely around the trunk) at roughly the height of the first cordon.  So I cut the trees off below where they were girdled, and new shoots started from the stump.  These were trained to wires.  Both trees did well the first year, but one withered died the next year.  The other tree was growing out well until it was chewed to pieces by rabbits (more on that later).  It succumbed to fire blight this spring.

In general, the the trees are growing very well and are very healthy.  The real problem is that 10 of the original 15 trees have never produced a flower or piece of fruit.  This is because the MM.111 rootstock is far too vigorous.  I have pruned enormous amounts of useless green growth from the trees the last two years.  These trees want to be 15 to 18 feet tall and be well established before they flower.  In contrast, a two-year sapling that I planted this spring, produced a dozen flowers 3 weeks after I planted it.  This is one of the big differences that the choice of rootstock can make.

I am now in a position where I have to figure out how to let the trees grow bigger while maintaining them in their current form in their current space.   I think that I am going to string wires between the four established cordons and grow new branches (leaving a lot less space between the cordons than I would like).  Going from 4 to 7 branches will let the trees get 75% “bigger”.  Hopefully, they will believe they are well established and start producing fruit.  The only other choice is to go taller, which is what I was trying to avoid in the first place when going espalier.

I had been warned during the first summer that I needed to protect the base of the trees from rabbits.  During the winter, the rabbits will chew off the bark around the tree and girdle it, thus killing everything above the chewed up part of the tree.  Since rabbits chew the tree close to the ground, they can girdle the tree below the graft.  At that point, all you have is a rootstock that will sprout back out in the spring.  So, I wrapped chicken wire around the base of all the trees.  This kept the rabbits away from the trees.  So after one year, everything looked good.   As noted above, in 2nd winter, the deer came along and girdled two trees (above the graft so I could grow the trees back out), and chewed up the branches that I had been growing.  So, I now put up a 5-foot wire fence around the orchard in the fall and take it down in the spring.  The deer could jump the fence, but apparently it’s not worth the effort.

Everything was working great until the spring of 2019.  I come out in the spring to do dormant pruning, and I find that most of the trees have been chewed up by rabbits (deer chew up the top of the branches and rabbits chew up the bottom of the branches).  So how does a rabbit chew up a branch that is 22 inches off the ground.  And look, there are three or four trees where rabbits have chewed up the branches that are 40 inches off the ground.  Can you say WTF?  Well, winter 2018-2019 had near record setting snow fall (50 to 55 inches of the stuff fell that winter).  And there were repeated times of thaw and freeze where the top of the snow turns hard and crusty.  So that winter, the rabbits walked on top of the snow and chewed on most of the branches at 22 inches off the ground and (thanks to drifting) lots of the branches that were 40 inches off the ground.

So now I have 36 inch chicken wire stretched around all the rows of apple trees.  No damage over the winter of 2019-2020.  Of course, it is now difficult, if not impossible, to weed around the trees, prune the lower branch, or spray the tree.  So I have to take down the chicken wire and put it back up to work around the trees.

The trees are alive and growing.  They look cool even if they are not producing fruit.  It’s a lot of effort, and I am far from convinced that it is worth it (since I am not getting apples yet).

I will grab some photos of the orchard in the near future and follow up with another post.