A heavy frost has laid itself down on your garden bed. The leaves have wilted and turned color. Now before you go off to cover you gardens with a warm blanket of hay, you may find yourself wondering exactly what to cut back and what to leave standing in the garden.
The Minnesota wintertime landscape can be a bit stark. Usually by December most of what we see is covered in snow. At this point of the year, since your landscape is essentially a field of white it can be aesthetically important to have some texture in the garden to break up the white monotony. Choose what to cut back in your garden based first on whether the plant in question will stand tall enough to catch snow and look pretty in the winter. Any herbaceous* perennial that stands shorter than about 12 inches is probably not going to be seen over the accumulated winter snow. Many of these shorter plants end up a soggy brown mush in the spring, and so it will just be easier to cut them back in the fall. Hostas are in this category. It can be challenging to make a garden bed look tidy in the spring with squishy rotted hosta leaves all over it. I like to leave standing, coneflower, persicaria, astilbe, mullien, milkweeds, and most grasses. Any tall plant that will catch some snow and cause a little texture to pop out of the white winter garden should be left to stand proud.
There are a couple of common mistakes to avoid while performing cutbacks. First, there are a few plants that are deceptively evergreen. The first fall that I worked in gardens, I got myself into a bit of trouble with “the boss” for cutting yucca back. Yucca, hens and chicks, pachysandra, and some low sedum are all types of evergreens that at a glance appear as though they may be herbaceous. Some plants, such as St. Johns wort and Russian sage can be thought of as being categorized somewhere between an herbaceous plant and a shrub. These plants have partially woody stems. Plants like these will not fully die back to the ground, and if left standing they will sprout greenery in the spring from the dormant soft wood of their stems. Perhaps worse than cutting back an evergreen plant, would be cutting into the green thumb of a gardener. God know's I've gawked at many a galling gory gash gouged in good gardeners gloves after gripping greenery for cutting without regard or guidance. That is to say, please don’t cut your fingers off, at least not in the garden.
When a hard frost comes along you must snip it. When there’s dead leaves in your palm you must snip it. Unless of course it looks good through the winter, then wait till spring and snip it into shape! Let the evergreens alone, and for goodness sake, snip the gardens, not the gardener! It’s not to late to snip it. Snip it good**.
*Herbaceous: A plant that does not have a woody stem, and dies back to the ground every year.
**Snip it good: An explanation for all those who are too young, too old, or for those like me whose parents didn’t let you listen to rock music in 1980. This is a play on the 80’s new wave song called Whip it. Thank you Devo!