Hi, I am a school teacher at Cecilton Elementary in Cecilton, Maryland. This...
Hi, I am a school teacher at Cecilton Elementary in Cecilton, Maryland. This past spring we planted a rain garden and are preparing for fall maintenance. I have found conflicting research about when to cut back perennials and tall grasses (spring or fall). I was wondering if you could give us some advice on when to cut back the following plants: Blue Vervain Cardinal Flower Joe-Pye Weed Monkey Flower New York Ironweed Woolgrass Bayberry Thank you so much! Anne Highfield
The bayberry is a shrub and should not be cut back.
Most people cut back perennial flowers depending upon their goals. If they want to provide a habitat for wildlife, then they'll want to leave any seeds or flowerheads over the winter so that birds can eat the seeds. Also, many beneficial insects overwinter in dead plant material. The broken stalks and dead leaves can also form a sort of protective cover on the base of the plant and protect it in a harsh winter.
These dried flower heads and seed pods can also be considered attractive and be left to provide winter interest in the ornamental garden. These are then cut back in early spring, say March, before new growth begins.
If gardeners do not like the appearance of dead stalks and flower heads, they can cut back the plants as soon as the plants go dormant or the leaves are yellow or brown in fall. The time of this will probably be somewhat different for each plant species, so most people would wait until they are all brown and then cut them back all at once. Care must be taken not to remove not to remove any of the green growth at the base which stays green over the winter in many plants. Besides doing this to achieve a "cleaner" look, if a garden is in a location that gets a lot of strong wind, dead top growth may be cut back in order to prevent it from catching the wind and the plants being ripped out of the soil, exposing roots to killing air and temperatures.
Thank you so much for your prompt, insightful response!!! Much appreciated!