You said to tell you what I want to learn to prune. A mugo pine. You showed one that was pruned but now HOW. Do mugo pine again, with feeling, okay? Thanks! - M.C. -
Here you go! Lots of photos to tell the tale. First, the story of an overgrown mugo cut back. Second, details of the tip cuts applicable to any shrub being shaped and/or "stopped" -- kept smaller than its potential. Third, notes for routine pruning of not-too-big mugos.
In cutting back or even simply shaping a mugo pine you must know how much you can cut. To learn that, look inside.
Look inside the shrub. See all the bare branches crossing above the line of black edging? Each must be cut back to a crotch to leave a side branch that has some greenery within the bed.
Some of these branches have no such crotch, so we'll cut them to the ground.
We can cut a pine back to any side shoot that ends in needles and a bud. However, the smaller that twig, the longer it will take to beef up and resume branching with gusto like the chubby mugos people love.
(That's what we did to that other mugo we reduced to "start over" size. ) For you, we'll cut back in stages so you can see the other options.
Follow the pointing finger -- that's a place where branches branch. If we cut to that depth we can reduce height and width by about 6 inches all around.
Inside, there are more, lower side branches with needles. So we know we can cut harder.
Is 18 months too long to wait for beauty at your front door?
Then start with a new dwarf mugo and two aims:
Here are less radical cuts made to another overgrown dwarf mugo.
("And what about a not-overgrown mugo?" you may ask. Clip as in photos 1 and 5 below, to remove every bit that crosses the lines you set for height and width, and thin the most congested areas so its interior receives enough light to maintain deep foliage. Hard to "show you" that since if you do it well the shrub looks the same after pruning as before. The shrub in photo 6 has been pruned that way.)
1. Pretend the rake handle marks the outer edge of the biggest mugo we want. So we'll cut all these branches so that they end at or behind the line, far enough back that they can grow for a year or two.
2. Notice the much-branched, leafless interior twigs. Each "Y" or "W" juncture marks a place that was shorn while the growth was all soft candles in spring. At each cut multiple tips developed as the whole layer advanced by the length of the "Y" or "W." Moral of the story: Shearing makes a plant dense but unless it's accompanied by cuts that go deeper, the plant keeps increasing in size.
3. This pine never had that thinning. It has all its foliage so close to the line that it now must be cut with great care...
4. ...back to the little bitty needled side shoots.
5. Okay, we've cut what crossed the line. More importantly, we cut some branches further so
light can penetrate to the depths.
6. Here is the shrub these branches came from. They are branches Janet took out to let light in.
She first cut all the way around the plant as in photo #5 . That left the plant smaller but looking almost the same as when she started.
Then she did what hadn't been done before -- cut out some branches 'way back to interior, needled side branches. Can you see the dark gaps? They are not very noticeable except where you are standing straight across from one of them, but are vital to keep the shrub healthy and prevent it from creeping larger each year.
7. The light will reach those tiny, weak bits of green in the center. They really need to build some bulk for a year or so before we cut this shrub as far back as the first example.
So that's that. Hope it helps you go cut your mugo, or make the determination to start over.