Hi,

November can be a good time to prune, but it depends upon the plants. If you prune in November, some plants are more susceptible to winter tissue damage. On the other hand, if they are early spring flowering plants, you will cut off the spring flower buds. 

Can you send me a list of plants you would like to prune? If you can give me the names of some of your shrubs/trees, I can help recommend the best times to prune them. 

Thanks,

Lindsey K. Kerr, MS, MHP (she, her, hers)
Consumer Horticulture Educator
Michigan State University Extension
33030 Van Born Rd.
Wayne, MI. 48184
Office:<personal data hidden>
mg.msue.msu.edu

Hi Bill,

Thank you for sending a list. It is very helpful. I'm going to go through the list and say when it is generally recommended that you prune these plants. You gave me common names which can be problematic at times because common names vary by region and I might think you are talking about one plant and it turns out you are thinking of something different. I hope I get these right!

Dwarf lilac. Best pruned immediately after it finishes blooming. You can prune them significantly, removing the oldest branches almost to the ground. Removing the oldest branches or canes can help prevent lilac borers from getting established.

June Berry Amelanchier. Best pruned when it is dormant, before leaves emerge in the spring. You will sacrifice some flowers when you prune. Amelanchier is generally grown as a tree or a multistemmed tree or tall shrub.

Viburnum. When you prune depends on what type of Viburnum you have. However, Viburnum are generally very tough plants. You don't have to worry about killing them, but you might lose flowers or fruit. Viburnum that have cane branching habits, like Viburnum trilobum and V. rhytidophyllum, should have canes removed almost to the ground. You can prune Viburnum species that have more of a single trunk much like a tree. You can prune Viburnum in early winter, once the leaves have dropped, or in late winter, before bud break. If you have Viburnum leaf beetle, late fall or early winter is a good time to prune to remove eggs.

Summer sweet. Prune in late winter or early spring before the plants leaf out.

Cornelian cherry. When and how you prune Cornelian cherry (Cornus mas) depends on the look of the plant you are going for. Cornus mas is often pruned to a single trunk and into a tree shape. I would wait until right after it blooms to prune it.

Spirea snowmound. It is unclear to me based on your photograph if you have Spirea ‘Snowmound’ or a variety of Japanese spirea. In either case, it doesn’t look like the spirea in front of your house need to be pruned. If you are growing them for the flowers, prune immediately after the flowers fade. You can prune damaged branches or unsightly branches any time during the growing season. If you are doing regenerative pruning, that is probably done best in late winter.

Blue Oregon holly. I think you are referring to a Mahonia species. Prune immediately after the flowers fade.

Rhododendrons (I only take off deadwood in the spring). Rhododendrons are typically pruned, when needed, immediately after flowers fade so that they have time to re-flush and set buds on new growth. If you prune them in late fall, they won’t bloom in spring.
Juniper. I'm not sure which type of Juniper you have and if it is an upright tree or a low-growing variety. You can prune junipers in late fall/early winter. Be aware that if you cut back to wood with no needles on it, they do not often push new growth. In other words, if you cut too far back, you might end up with naked branches.

Red twig dogwood. Best to prune in late winter or early spring. Cut older branches (the bark turns gray) all the way to the ground. Prune out old wood annually and your shrub will keep the red twigs that they are known for.

I do not recommend sheering any of these plants.

I know you wanted to be able to get pruning done this fall, but it looks like spring and right after bloom is best for several of your shrubs.

Please let me know if you have additional questions. 

Lindsey K. Kerr, MS, MHP (she, her, hers)
Consumer Horticulture Educator
Michigan State University Extension
33030 Van Born Rd.
Wayne, MI. 48184
Office:<personal data hidden>
mg.msue.msu.edu