When should you prune?
What pruning is not ~ common misconceptions!
How to choose where to cut...pruning should stimulate a response
If you flat-top a shrub (are you shuddering yet?) it tries to push out new shoots all over. Fine, if ugly is your goal. So please no buzz cuts. Save those for the 80's!
But if you want graceful bushes dancing in your landscape, you'll have to make varied, selective cuts of crowded branches inside the shrub.
Aesthetics always plays a monumental role in pruning!
Make pruning cuts 1/4-inch above an outward-facing bud or node (the spot where the branches grow from) slanting the cut outward.
On larger tree branches, make all cuts just outside the branch collar (the thick area where the branch connects to a trunk or another branch.) Never cut in between nodes or branches, leaving a stub. Die-back and rot will follow! So bad.
If the bush is too big or blocking a window, move it. Don't whack it down to size!
Then new growth thickly emerges only at the top of the bush and soon only bare sticks will show beneath the canopy.
C'mon, you've totally seen this in a neighbors' lawn! Again, this is why you need to reach inside the plant and remove the inner branches, letting light enter.
Pruning inside the shrub is truly the key to it all!
Always cut just above another branch or bud, preferably one that faces outward. After you cut, the energy will go into the bud or branch you left behind.
So if you cut just above a small branch that is growing in a desirable direction, that is good! The plant's energy will go in that direction. A new branch will reveal itself next year.
The general idea is to allow sunlight to penetrate as many tree or shrub branches as possible.
What needs pruning...
2.) Diseased, dead or dangling branches that are threatening people, property, or the plant's health: In case of disease, you might want to get an official diagnosis. As a general rule, make cuts several inches beyond the diseased section.
3.) Rubbing or crossing: This is where you use your artistic flare and judgment skills. Branches that are rubbing together will lead to a wound which leads to damage, poor structure or disease. So you must choose the desirable branch and cut out the other.
4.) When a plant is too big. When that shrub or bush crowds your window or sidewalk, rubs up against the house or blocks your view, that plant was put in the wrong place originally! It was never given the right amount of space and should be transplanted, not necessarily pruned.
5.) Some plants, like my hibiscus bushes were becoming so crowded with branches in the center that sunlight couldn't get in to support the flowers or foliage. With my lemon trees the crowding was affecting fruit production. If poor pruning was done in the past (ahem...buzz cut) all the growth goes on top.
6.) Some plants are prone to diseases that thrive in crowded conditions, thinning them to increase air flow can help.
7.) We observed this past weekend orchard trees that were pruned low and flat to facilitate maintenance and likely harvesting, too. Some fruit plants or roses are pruned to increase fruit or flower size.
Timing of pruning...You nailed it...
Once the plant breaks out of dormancy and leaves form because the food reserves are in the leaves; you lose and waste those carbohydrates when you cut off branches. Not good!
It's also true that in late winter few insects or disease spores are present to invade the wounds, and the wounds seal over quickest with spring coming.
So big sigh. Fall pruning or even early winter pruning is far from ideal because wounds heal more slowly, leaving the plant vulnerable to disease or pest invasions.
Besides, without the leaves, it's easier to get a visual of the tree or shrub as a whole and make better judgement calls as to where to cut.