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robin44444

What is the latest date to prune perennials here?

robin44444
11 years ago

Family situation decrees I have to wait until the latest date possible to prune my perennials. What is the latest date I can prune grasses, shrubs, and perennials? We live at about 6100 feet in Southern Colorado. Thanks very much.

Comments (3)

  • WxDano
    11 years ago

    Shrubs depends on the type of shrub. Grasses somewhat less demanding, but pretty soon. Perennials depends upon the type of perennial. Also the weather is a factor.

    So no general or firm date. The plant dictates, as does the weather.

  • Skybird - z5, Denver, Colorado
    11 years ago

    Hi Robin,

    With grasses and with perennials that die all the way down to the ground you want to cut them back before they start growing too much in spring or you wind up cutting off some/all of the new growth and they have to start over again. Check them out pretty closely, sometimes it's not very obvious when they start growing because the new growth this early isn't bright green! When cutting down perennials that die back to the ground remember that if you leave more than a few inches of the old dead stems and foliage on them it'll be visible all summer. Things that are evergreen or semi-evergreen need to be trimmed soon too. I trim things like that back far enough to get rid of any foliage that has gotten ratty looking over winter--and that varies widely from year to year. But remember that if you cut back any perennials that bloom in spring now you might be cutting off this year's flowers! Spring blooming perennials are best cut back right after they finish blooming.

    If you have shrubs that bloom, try to cut them back right after they finish blooming or you might wind up cutting the following year's flowers off. For instance, with spring blooming bushes like lilacs, they form their flowers for the following spring sometime in late summer or fall of the previous year so if you cut them back in spring you probably won't get any flowers that year. For things that bloom over the summer, try to get them cut back by fall or early winter. Shrubs that don't bloom, it probably doesn't make a whole lot of difference, but even if they don't bloom, most shrubs will already be budding for the coming summer, so pruning them now will possibly cut off some of "this year's growth" and they'll get started actively growing later than they would if they weren't pruned now. That might not necessarily be a bad thing if you don't really want them much bigger than they are now! [I have some kind of a Viburnum by my front door that's trying to eat my house and I have cut it back SEVERELY up to three times a summer--secretly hoping it'll die--and it just keeps going and going and going.......]

    Skybird

  • robin44444
    Original Author
    11 years ago

    Thank you, both. Wow, it looks like I'm in trouble. I was hoping to wait a month or two.