Protecting Perennials in the Winter by Donna Duffy

Rudbeckia, photo by Donna Duffy

Colorado's relatively warm days and cold nights, extreme temperature fluctuations and drying winds can wreak havoc with many of our commonly planted perennials. Planttalk Colorado offers the following suggestions to protect your perennials over the winter.

Diascia integerrima, Coral Canyon Twinspur, photo by Donna Duffy

Dehydration is a common problem when snowless winters occur. A layer of mulch several inches thick helps retain soil moisture. This mulch should be coarse and loose to permit air movement to roots. Root tissues continue to metabolize in the winter and requires oxygen for this process to take place. Reduced soil oxygen level increases the aggressiveness of many soil pathogens. Mulches which pack down should be avoided.

Watering at least monthly under dry winter conditions recharges the soil profile with moisture critical to plant survival. Whether you removed dead foliage in the fall or are waiting until spring, mulches provide the best protection for your perennials. Many types of mulches are available, and no matter which you choose, there are a few guidelines you should follow.

Mulches do a better job of insulating plants when space is allowed for air to circulate. Mulch that packs down to a dense mass during winter can cause mildews and molds to form. Shredded leaves from deciduous trees and pine boughs from discarded Christmas trees offer great winter protection. A good organic compost used as mulch is also effective and can be used as a soil amendment in the spring.

Established perennials and bulbs benefit from mulches that are applied after the ground freezes, because mulches don't allow soil temperatures to fluctuate as much throughout the winter. Check your mulch throughout the winter months to make sure it hasn’t blown away and exposed bare ground. In the spring, don’t be in a hurry to remove mulch or the plants will begin to grow too early. 

Perennials thriving after winter's freeze, photo by Donna Duffy

Follow these few simple tips and your perennials will reward you with another summer bloom!