Watering in the Winter

As another growing season comes to an end, our carefully cultivated plants are storing up energy for fall and winter. It is easy to assume that our gardens and landscapes will automatically prepare to hibernate for the winter, and then come back with a bang in the spring. Many flowers and shrubbery do have this superpower, but we’d like to call attention to those plants that need our help. Like evergreens! Watering our sweet greenery in the fall is just as important as it is in spring, and My Thyme Gardens is advocating for each tender bud.

Record low temperatures in the past few winters urge us to double down on our vegetation consideration, and drying southern winds are the most damaging. Rhododendrons, azaleas and boxwoods are abundant in the Macomb and Oakland area, and are particularly susceptible to winter damage. Without proper watering and care, they become dehydrated. Since their cell walls rely on water to protect them against stressors like wind and strong sun, these cell walls burst. The structural integrity of the plant is lost, as are the chances of making it through a Michigan winter. Read on to learn specifics of each shrub, and then we’ll tell you the secret to having strong, lush shrubs year-round.

Boxwoods, those ubiquitous, broad-leaved evergreens, are especially vulnerable to what we call “winter burn.” This is when the sun comes out in full force, dazzling the snow-capped landscape. When the sunlight reflects off of the surface of the snow, the leaves of the boxwoods are blasted. This typically happens on evergreens that are south-facing. Combine that with high winds making the leaves’ moisture evaporate, and we can safely conclude that winter is hard on our evergreens. Salt spray is another source of stress for this foliage; when applied to icy roads and sidewalks, the salt can travel to our gardens and dehydrate greenery with exposed leaves. Ouch! Our friends at MSU reassure us that some winter damage can be offset by careful pruning – but we aim to avoid any winter damage as much as possible.

Rhododendrons and azaleas are another Midwest favorite, and even though Michigan’s winter climate is hardcore, we’ve seen too many success stories to remove these beauties from our gardens! Creating a microclimate for these shrubs can increase the chances of success. This can be as simple as planting them closer to your house for a slightly warmer temperature, or planting close to a larger tree or shrub that protects it from frost. Choosing hardier varieties (we recommend PJM Rhododendrons and the Northern Lights Series of azaleas) will bump up the likelihood that they’ll survive Michigan winters. Make sure they are planted in soil that is acidic (learn about soil acidity here) and able to drain effectively. Another tip is to plant these early spring bloomers in a north or northeast facing area of your home. They’ll love the morning sun, and be protected from the intense, midday sun all winter long.

And now, what you’ve been waiting for: the most effective way to protect and nourish your rhodies, azaleas and evergreens throughout the chilly conditions is to keep up your watering routine throughout the fall. As explained in the beginning of this post, this maintains the cell wall of the plants. As temperatures reach below 40 degrees, you’ll need to switch to winter mode. Once a month, choose a day that is above 35 degrees. Fill a gallon jug of water, and pour it at the base of the root. This sounds simple, but the challenge is remembering to water once per month! Try checking the weather forecast ahead of time and setting a reminder on your virtual calendar.

Yews and arborvitae are other Midwest favorites that also require consistent watering after summer, but luckily, they are not as susceptible to winter dehydration as those mentioned above. Often, we turn off our sprinklers mid-October, even though our gardens still need to be watered 1-2 times per week! Follow the aforementioned watering protocol and your yews will bound into spring seamlessly.

Other than consistent watering post-summer, these evergreens also require acidic soil conditions. Try an organic soil acidifier as the weather turns chilly, bringing a boost of nourishment to your evergreens. Apply a light dusting to the dripline twice before it snows, and then resume once spring has sprung.

Do you have questions about how to take care of your garden in the cold weather? Drop it in the comments below.

Until next thyme,
My Thyme Gardens