This group of “low junipers” is often either not pruned or pruned incorrectly. Not pruning can result in run-away growth where these junipers outgrow their space. Incorrect pruning can alter the plant’s natural growth habit and cause it’s health to decline.
Right?…This is the first thing to ask yourself before pruning. The cuts you make should support the natural growth habit and shape of the plant.
Low, spreading junipers naturally want to grow horizontally and get much wider than tall. Their branches shoot out; instinctively wanting to dominate and get longer (this is known as apical dominance…you don’t really have to know this). In a wide open space where you’re looking for maximum coverage, this growth habit is ideal. In these circumstances you can allow the plant “to do its thing”.
Often, however, low junipers are used in limited spaces. If left unchecked, they’ll out-grow that space and, well…the solutions to that are not pretty.
Selective pruning, as you probably know, is time consuming. As the name implies you are selectively choosing where on the plant to make each cut.
There is no power equipment that significantly automates this process. There are some people that “shear” these plants with power shears. That’s incorrect and a disaster as it turns them into manicured shapes and promotes dense growth only on the ends of the branches.
In the second picture above I’m choosing branch ends that are growing noticeably faster and longer. I then move down the branch to a point within the secondary, slower growth – and make the cut. This is done throughout the plant. Try to work from one area out and not jump around randomly. Always be conscious of the plant’s natural shape. Step back occasionally to check your work and adjust your cuts if necessary.
The first picture above shows a newly planted Juniper ‘Parsoni’. The shape of this new, low, spreading juniper is misleading. Notice how the side growth is somewhat stunted as compared to the top growth. This is because this plant is coming from a nursery where it had been stored in close groups – probably almost touching one another.
The last picture is a low, spreading juniper that was just “selectively” pruned. (Click on it for a bigger image.) Most of the long ends have been pruned back, and the natural shape preserved.
Your low, spreading juniper will have a long, beautiful life if you prune them “selectively”. Of course, remember how equally important spacing them correctly is when planting.