Steele: Changing practices for fall perennial clean-up

I leave most plants until spring. This way there is food and cover for the birds, visual interest for the on-looker.

Forty-five years ago with my first garden in Oyama, I cut everything back after frost.

This almost eliminated spring clean-up but the garden had no winter interest. Now, I leave most plants until spring. This way there is food and cover for the birds.

Also leaving the dead top-growth on perennials gives them some winter protection.

When I plan my gardens, I now factor in winter interest.

Evergreen perennials such as lavender are there all year.

I am enchanted by the magic of hoar frost or snow on the ornamental grasses and the seed heads of rudbeckia, echinacea, sedum ‘Autumn Joy,’ yarrows and any other sturdy stemmed perennials.

All winter long I can watch and hear every breath of wind in early grasses such as calamagrotis ‘Karl Foerster as well as the spectacular fall blooming miscanthus varieties and ravenna grass.

Everything that dies down to its roots will be cut back in spring.

The two main things I want to be sure to do before winter are weeding and collecting seeds.

My gardens are very full, so once the plants have grown up by late June, there is little space for weeds to grow. I have a good layer of mulch everywhere on top of the soil.

This really cuts down on weed growth, as well as holding moisture and feeding my plants during the growing season.

Perennial weeds will grow as long as the ground is not frozen so taking them out now prevents a big task in early spring.

During August I stop dead-heading. This leaves seeds for winter birds and for collection.

Now the seed heads are dry enough to save in paper envelopes or bags. In winter I’ll clean the chaff from the seeds and package them up for gifts.

If there are plants I want babies of, I often shake the seeds onto bare soil where they will begin growing in spring as soon as conditions are right, taking advantage of spring moisture so they don’t have to rely so much on me remembering to water.

I generally cut back any plants that are flattened by frost, such as daylilies and hostas.

I no longer grow plants that attract diseases such as mildew, but when I did, I would always clean these away in the fall and put them into the yard waste bin to avoid disease spread.


These days I am taking lots of photos of my gardens and making notes of what plants to divide for next years xeriscape plant sale at the unH2O Xeriscape Garden.

I will be doing the last free garden tour of the unH2O Garden (in front of the H2O Aquatic Centre, 4075 Gordon Dr.) on Sunday, Oct. 28, 1 p.m.

We’ll look at what is still blooming and I’ll give more fall clean-up tips.

Gwen Steele is executive director of the non-profit Okanagan Xeriscape Association. Learn more about Gardening with Nature and plants for the Okanagan on the website at