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In my area of Northern Virginia, boxwood have had new leaves for six weeks or more already. Buds that were set last fall extended at the beginning of April, give or take a little, and the trees have had time to recoup some of the energy that was used for that spring push. The new growth is still somewhat tender — not fully hardened off — but this also means it is still easily distinguished from last year’s growth. This is one of the reasons I think now is a great time to do some refinement pruning.

I hope I am not overselling the level of development of my boxwood by using the term “refinement.” The examples I am sharing may not meet the highest standards for bonsai, but the branching and leaf pads are at a stage in development that I would consider refinement.

It may also be worth distinguishing refinement from maintenance. The former term suggests adjustments are still desired, while the latter does not. The boxwoods I am pruning today definitely have some areas that need adjusting, but the overall branching structure is set.

Above is a single trunk example shown prior to any pruning. You can see the the foliage pads aren’t very neat, and cleaning these up is one of the goals.

You might also notice that the new, lighter colored growth seems to be pretty consistent across the whole tree. It’s not longer on top and shorter on the lower branches as can often happen. In fact, just about ever new shoot has 6-8 leaves. This is a good sign that the tree has well balanced energy and a signal that this tree is in refinement. Another goal as we work is to maintain this balanced energy.

So here’s what I do — step one, remove the growth extending downward — probably no big surprise, right?

The opposite growth habit of boxwood manifests in a predictable manner. If one pair of leaves is on the left and right side of a branch, the next two will be on the top and bottom. Buds grow from the base of leaves that get sufficient light, so you will likely have situations, like the one shown above, where you have a branch growing up and a corresponding branch growing down.

Remove those downward pointing branches, focusing first on the bottom sides of each pad. Before long, the bottom side will seem more orderly and the branches you missed will be easier to find.

As you go, you can also pluck some of the old leaves, especially those that extend downward and any you come across that are discolored or damaged. Be careful, though. Sometimes an innocent pluck at the base of a new branch can break off the new growth with it.

Don’t get too obsessive just yet about downward growth. Give each pad a good pass, and know that you will find more as we move to the next stage.

Even that first pass makes a big difference. Here’s the before image on the left and then the tree after the first pass removing downward pointing branches on the right. The cleaner lines of the bottom sides of the pads already make the tree seem more refined.

The next stage is to reduce the shape and density of each pad by working from the top. Just as it was from below, there are two operations that you can do simultaneously: pruning branches and plucking some of the old leaves.

You are not trying to remove ALL of the old leaves, just the ones that are damaged, extend beyond the silhouette you want, or make an area of branches and leaves far too dense.

As you prune the new growth avoid pruning all of the new leaves from any branch tip! The new leaves are much more efficient than the old, and if you remove all the current year’s growth you may not get new growth from that branch next year.

As you prune, you will easily be able to distinguish the dark green old growth from the brighter new. In the branch below (removed from the tree for visibility) you can see how each pair of leaves emerge from the branch at 90 degrees from the last. In this case, the scissors are placed to remove two pairs of new leaves, and leave two pair (four new leaves) below the cut.

Keep in mind that in some cases, cutting back to the first pair of new leaves may not reduce the silhouette as much as you want. When this is the case, look a little deeper. You will often find that you can remove the too-long branch back down to a point where you have two other fresh shoots.

How far to go is a matter of aesthetics. What shape do you want from those pads? How perfect do you like the lines? How much space do you want to see between pads and between branches?

This feels like a good place to stop on this one. I actually find that taking a photo, and then analyzing that photo is one of the best ways to determine what needs more work. In fact, the photo of the twin trunk tree, shown at the top, helped me see that I want to further thin and lighten the first branch.

I may work on that yet, and I see it as something to look forward to. I find refinement pruning on boxwood extremely satisfying! I hope you do too.