- Author: Dustin Blakey
I often get asked about whether fall is a good time to prune the landscape. While the mild weather makes it attractive to work outside, it's probably a good idea to wait, but you won't usually kill a plant outright by pruning. I don't even think about pruning until late winter. (In cold winters, I have seen some winterkill on fall-pruned plants that should have been hardy, but these are usually new plants or have other issues.)
On large orchards, practicality makes the pruning season start fairly early so that the job can get done in time, but homeowners have a lot more flexibility. Don't set your pruning schedule based on what you see in the Central Valley or down south.
Here are some pruning tips for the Eastern Sierra.
Summer-flowering trees & shrubs, modern roses, and grapes: Wait as late in winter as you can bring yourself to do, but before it gets warm. It's fine to do some light pruning early on, but wait to do the final pruning. I'm lazy and only want to prune once. March works well in these parts. An advantage to waiting is you can see what was damaged during winter and remove that. Low desert folks will do this in January.
Spring-flowering ornamentals and once-blooming roses: Wait until they flower and then prune them then.
Perennials: Do not cut back the dead foliage in winter. Leave it. Pretend it's a desireable feature if you must. The foliage protects the crown and roots from freeze damage. Remove the dead stuff just before the new growth starts. Early March is probably good. This goes for ornamental grasses, too. Folks near Lone Pine and points south can do this a bit earlier.
As a couple examples, in my admittedly non-scientific trials in Arkansas (USDA Zone 7) garden mums always made it through their first winter if not pruned even without mulch, and maybe 80% made it through if they were pruned in fall. Lantana camara always survived better if I waited until it was absolutely positively dead. I always waited until spring in my yard. Whenever I hacked it back in fall, it failed to overwinter. (Always mulched this.)
Hydrangeas: Even though their name means water-lover, they are still grown in the Owens Valley. Whatever you do, don't remove those ugly, "dead" sticks. That will be spring's flowers. Wait until they have finished blooming. The only time they need pruning is if they get too big. Same reason you'd need a haircut. When I'm sure those sticks are really dead, I remove them. Usually May. Get it done before June 25.
Palms? Not too many here in Bishop but here's some info. Maybe south Inyo folks will find it useful. I've seen a lot of mis-pruned palms there.
Remember, just because you have a plant and a set of pruners, that doesn't mean the two need meet up. Most plants do not need annual pruning. Always have a reason since you can't just glue the branches back on. Homeowners with pole pruners often do more harm than good.
Big, sick, dead, ugly, dangerous, or fruit/flower management are all good reasons. Because your neighbor does it is not a good reason. Nor is having a pruner in the garage.
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