Ready to head out into the garden? A pair of sharp hedge shears will make your work go quickly. Keep pruners handy for the tougher stems. Cut perennials back one to two inches above the ground, so you can still see where they are. Pull out spent annuals. This is a great time to get the weeds out- doing this chore now can save a lot of headaches in the spring. Top dress your beds with a layer of compost or chopped leaves (I like to run them over with the lawnmower), being careful not to cover the crowns of the plants.
If you have a lot of Hostas and you don’t mind waiting for frost, they will turn to mush and can be easily raked up. Ornamental grasses can be cut back in late fall or, if you like the way they look in winter- left up until spring. Tie them up before you cut them to make cleanup easy. Cut grasses 12 to 18 inches high.
Some plants with attractive seedheads- Black Eyed Susans or Coneflowers, for example, can be left up for winter interest, and to provide food for the birds.
When you are ready to cut back your perennial garden this Fall, keep in mind that certain plants should be left alone until mid to late Spring, when the weather starts to get warm. It is fine to trim the spent flowers off of plants like Lavender, Russian Sage, Candytuft, and Santolina- but cutting into the woody stems could cause them to die back in the winter.
Heucheras, Hellebores (Christmas and Lenten Roses), and Tiarellas (foam flowers) remain mostly evergreen through the winter. Remove the old leaves in the spring when the new leaves or flowers emerge.
Some perennials need the extra protection of leaves to help them survive colder temperatures. Hardy mums and coreopsis return better and more vigorously if they are not cut back in fall.
While peonies can (and should) be cut back one to two inches above the ground now, tree peonies should never be cut back.
Questions or comments? Please feel free to comment in the space below-Happy Gardening!
Cindy Hollett, MCH (Massachusetts, Certified Horticulturist.)Vetorino’s Landscape and Irrigation