Originally published in the 2020 November Issue of the WildFlower News
Fall maintenance
Most of the wildflowers and grasses in our Edmonton native beds are perennials. They’ve evolved to survive harsh conditions by developing strong root systems. Grasses and many forbs also retain nutrients above ground through the winter, giving them value as forage for over-wintering grazers such as deer if you happen to live near a creek or ravine. Dead stalks are also important for native bees and other insects to burrow into, until spring.
Here are some fall maintenance basics to guarantee your perennials make it through winter while allowing wildlife their natural capacity to find food and shelter through to spring:
• Remove as many weeds as you can, including their roots and seed heads, before the seeds spread.• Thin out the smaller volunteer natives that have sprouted. You can transplant them into pots for spring or fill in
empty spaces.
• Cut off the top portion of the taller or more aggressive plants such as aster, giant hyssop and common tall sunflower. It allows the plant to focus on roots before the onset of winter. But leave 30 to 35 cm, as these dead stalks are important for overwintering pollinators. The seed heads don’t have to be wasted though, as they can be left in a tray for wildlife and birds. Or collect them for sowing next season.
• Mulching with leaves or even the dead material you’ve cut back provides an extra layer of insulation and retains moisture.
• Don’t forget to water. Perennials rely on strong roots to come up again in spring, and giving them a soak before freeze up gives them a boost before heading into dormancy.
• Plants that are in pots, even natives, need to be protected from extreme weather. A good option is protection with burlap, or put them into a sheltered space away from desiccating wind and exposure.
• Don’t overdo it. Native plants, with their accompanying layer of debris and above-ground dead material, are a haven for hibernating pollinator insects and arthropods. Central Alberta is also home to the tiger salamander, which overwinters in spent plant material or in the ground, protected by plants.
With some attentive care, you can maintain your native bed’s shelter and food storage capacity so important for overwintering fauna, while at the same time showing your neighbours you’re not leaving it to grow wild and weedy.
The variety of textures and colours of native plants’ dormant stage are beautiful against a snowy backdrop. Let them keep adding to the splendour of all our Edmonton seasons.
Giant hyssop stalks, among others, provide an invaluable overwinter haven for hibernating pollinators.
Green needle grass is one of several bunch grasses that offer wildlife a food source over winter.
Leave dead plant material, such as these artemesia stalks, as mulch and a seed source for overwintering mice and birds.
Seed heads that you cut from the main plants can be left on a tray or a log for overwintering mice and birds.Mulching with leaves or dead plant material insulates native perennials from extreme temperatures and retains moisture.