How To Grow: Fall Perennial Flower Care

Learn about caring for your perennial flowers in fall including how to cut back the plants, fertilize, add compost, weed and protect the plants from winter.


Fall is the perfect time of year to clean up and cut back the perennial flower garden. I know you might be tired of doing all those gardening chores but this is an important one. When you cut back and clean up the flower garden you’re reducing the amount of insects and diseases you’ll have for next year. You reduce the amount of weeds that are around and you’ll strengthen the root system. Let me show you how to do it.

Although it’s tempting to cut back all the perennial flowers at once there’s a reason to be more selective. Leaving some seedheads on plants, such as echinacea and rudbeckia, make for great food for the birds. Gold finches and other small birds love to feed on these seeds in fall. Also, the black seed heads of these plants add interest to the garden in winter, especially when there’s snow on them. Of course, if you have little time, cut your perennials back whenever you can. Come October, even if the plants are still green like this peony, you can still
safely cut it back and not hurt the plant.

Another reason to cut back your perennials is to prevent excessive self sowing. Plants like this Baptisia can spread the seed pods. They will produce a lot of seeds. It’ll go all over the garden. Echinacea, rudbeckia, and a number of other perennials will do this as well if you aren’t good about deadheading like I wasn’t here. It’s still not too late to do it as long as the seeds haven’t spread everywhere. It’s okay to have some self sowing, but these will go overboard meaning you’ll get too many seedlings and they become weeds in the garden.

Some perennials need to sow their seeds. Hollyhocks and foxgloves are biennials or short-lived perennials. They’ll drop their seed in summer and new plants will sprout in fall. These seedlings will overwinter and provide new blooming plants for next year to replace older, dying ones. So leave some of these seedlings in the garden.

Once you’ve cut back your perennials it’s time to weed. I know you might be sick and tired of weeding, but it’s really important to kill the weeds that are there now, like dandelions and burdock. They’re gonna be the first things to grow in the spring. So get them out of the garden now. By digging out these perennial weeds now you’ll have less work to do in the spring because you have a lot of other chores to do that time of year.

For perennial weeds I like using this Cobra hoe. It’s a nice tool and allows me to dig out the roots faster. For annual weeds just cultivate the ground with a hoe and chop them. Stop them from sowing more weed seeds. After cutting back your plants and weeding now it’s time to add a layer of compost. Perennial plant roots will continue to grow until temperatures reach about 40F degrees. So even after cutting back the foliage the roots will be expanding for next year’s growth. Compost helps slowly feed them and builds a general fertility and tilth of the soil. Add about a two inch thick layer around your plants. Based on a soil test, you can also add lime, sulfur or other organic nutrients to the soil. These will break down by spring.

Taking time to cut back your garden, weed it, and feed it with compost and fertilizer will pay you dividends
with beautiful growth next spring.