Why do we prune fruit trees in February in Minnesota?

This week has been a great week for pruning our apple trees.

Fruit trees need to be completely dormant before pruning which is why it happens in the dead of winter.  Unfortunately pruning at the wrong time can cause a tree to die off; if it is not in dormancy, the wounds won't be able to heal properly and it will be put under too much stress.

A few beautiful apples from our 2020 Honeycrisp harvest!

I bundle up in my snow gear - boots, snow pants, and my heaviest coat.  Wool socks are also a must!  My dog Sadie joins us when pruning as well, we don her winter coat as she's usually sitting and observing and not moving around too much.

My dad and I prune together.  We choose a day that isn't going to be too cold, too windy or too sunny.  If you've ever tried to prune something looking straight into the sun (especially when the light is reflected off the snow), you understand why!

The goal with pruning young trees is to help guide them as their branches grow out.  Many fruit trees when you purchase them at the store will have a number of branches that are growing straight up.  Ideally, we want only one "leader" (the branch that grows straight up from the middle of the tree).  We want the rest of the branches to grow out to fill out the space.  When pruning we are looking at the best ways to give each branch ample space.  In the spring we guide the branches by tying them to fence posts so they grow as we want them to.  Winter is not a good time to tie the branches; that is something that needs to be done when the trees are flexible in the spring.

This gives you an idea of what our staking looks like.  This method was done when we planted these trees in May 2020 when the branches were quite flexible.  Tying the branches helps to support them and allows us to guide the tree in the direction we want it to grow.

For mature trees, the goal is to prune for ideal fruit production.  Many mature trees will have "suckers" which are branches that grow straight up out of the main, mature branches.  Our pear tree and McIntosh tree grow many suckers that we have to prune off on an annual basis which can make the trees quite crowded.  Though they can potentially grow fruit, it is not ideal to have branches growing straight up as it can interfere with growth of the other branches.  We are also looking to prune out branches that might cross each other.  When growing fruit, we want to give each branch the appropriate space to grow and if the branches are touching or generally too close together, the branch will not grow appropriately.

If you look at our Patten pear tree, the mature tree to the left of this picture, right in front of the barn, you'll see the "suckers" shooting straight up.  These can produce fruit but they don't often produce a lot of fruit, plus they can interfere with the growth of the other branches.  This pear tree is notorious for its extensive suckers every single year!

Additionally, for us the goal with the mature trees is to keep them from getting too unruly.  Full size trees can be difficult to get all the fruit off of.  Though a bigger tree might seem like it will get more fruit - which in a way is true - but we also want good quality fruit.  When a mature tree is able to spend more time growing the fruit and less time growing branches, it will put more energy into the fruit leading to more, better quality apples.

Finally, we are looking for branches that may have died off.  It is natural for mature trees to have branches die.  Dead branches snap very easily because there is no water going through them anymore.  They will also have a gray tint to them.  Clearing out the old wood allows the tree space to grow with its remaining branches.

We had to take a number of dead branches off of this Haralson apple tree this year.  This provides the rest of the tree with space to grow.  It is one of our more mature trees at about 30-35 years old and unfortunately we don't think it has a lot of life left in it.  Thankfully we did plant two new Haralson trees in 2020!

The basic tools you will need for pruning apple trees are a good quality pruners (Felco is my absolute favorite!) and a good quality lopper.  Depending on the size of the branches you need to remove, a hand saw can also be beneficial.  We also use my dad's pole saw which is very helpful especially when reaching the branches at the very top of the tree.

We bought this loppers a few years ago and it quickly became a favorite tool.  This helps to remove medium - large size branches!

Here in Minnesota where we are in zone 4b, pruning is recommended when the tree is in full dormancy.  February and March are great months to work on pruning your apple trees!