Sauk County Gardener: To cut back or not – that’s the question

“The flower doesn’t dream of the bee. It blossoms and the bee comes.” ~Mark Nepo

It seems that we may be finally getting a break from the heat and humidity. I’m hoping so, as mid-60- to mid-70-degree temperatures will help my tomatoes finally start to really ripen well. I was concerned I wasn’t going to have enough ripe tomatoes for this year’s Tomato Tasting event sponsored by the Sauk County Master Gardeners Association. There were nearly 30 different varieties that were brought in to display and taste! I brought in 13 varieties from my own garden. Attendees were able to taste samples and vote for their favorites. There was a tie for first – Tomatoberry and Malachite Box, second place went to Sungold, and Paul Robeson won third. If you are looking for a new variety or two to try in your garden next year, consider these delicious and beautiful tomatoes.

With all my tomatoes starting to come in, it’s hard for me to keep up with processing all of them. We eat as many as we can fresh, but that doesn’t even make a dent in the number of tomatoes I pick in the garden. If you are experiencing the same problem and have room in your chest freezer, consider freezing them whole until you have time to work with them. It is important to note you should use the tomatoes only for cooking or seasoning as they will not be solid when thawed. I wash, core and freeze them with the skins on them. When they are thawed, the skins slide right off making it much easier than blanching.

Since all of my tomatoes are needing to be dealt with, it’s hard to get out in my perennial beds. Now is the time of year when spring and summer blooming plants start to look straggly and tired. When I do have time to visit the perennial beds, it’s hard to resist just cutting everything back. Knowing what and when to cut back is important and can help break up your garden maintenance into more manageable chunks.

Deciding what and when to cut back falls into three categories – (1) Should be cut back, (2) Shouldn’t be cut back, and (3) It depends. Here are a few that fit in the first category that “Should be cut back” to prevent disease: Monarda (bee balm) and tall Phlox (both get powdery mildew), plants that look ratty/dead, plants that provide homes for pests, such as hostas (dead leaves provide homes for slugs to overwinter), or plants that don’t provide any winter interest.

Don’t cut back perennials that are evergreen or low growing – Hellebore or Heuchera are two that come to mind. Also, leave standing perennials that need their foliage to provide insulation for their roots – Chrysanthemums, Agastache (anise hyssop) or Kniphori uvaria (red-hot poker).

Plants that fall into the “It depends” category are ones that are late emerging in the spring such butterfly weed and balloon flowers. Leave them standing or cut them back to two to three inches high so you are less likely to accidently plant over the top of them or dig them out. Plants that provide food or habitat for birds and beneficial insects in the winter such as Echinacea (cone flower) and Rudbeckia (black-eyed Susan) also fit in the “It depends” category. Finally, consider leave standing plants that have excellent fall color or provide winter interest such as ornamental grasses, Baptisia (false indigo), and Sedum.

Once you’ve decided what you should leave standing and what can/should be cut back, get out your handy bypass pruners. Only cut your perennials back after they are dormant – this is typically after a couple hard frost. Once your plants are done blooming, they need their foliage left standing awhile to put energy back into their bulbs, corms, tubers, tuberous roots, rhizomes and roots. Remove any materials that are diseased and dispose of them in your trash or bury them – just don’t put them in your compost as most of our compost piles do not get hot enough to kill the various plant diseases. Cut your plants back to two to three inches above the crown of the plant. This will help prevent your plants’ dead foliage from becoming havens for fallen, blowing leaves. If you get too many leaves piling up, the leaves can provide homes for mice and voles. Also, some perennials make emerge sooner in the spring than they should because they are fooled into thinking it’s warmer than it really is. If you can’t complete your cutting back in the fall, do it as soon as the snow melts in the spring. Fall is just around the corner; instead of trying to hurry and cut everything back before winter, selectively cut back your perennials, and use the rest of your time to enjoy the cooler fall days.

Jeannie Manis is a Wisconsin-certified Sauk County Master Gardener volunteer. If you have any gardening questions, please contact the Extension Sauk County by emailing to trripp@wisc.edu or calling the University of Wisconsin Madison Division of Extension Sauk County office at 608-355-3250.