Have your green thumbs been itching to get outdoors and into the dirt? Ours too, like they do every year once that sunshine hits us in the face. And yes, we’ve all heard that Victoria Day weekend is when we can start gardening again, but remember that Mother Nature is in charge of the schedule and some years are last frost can be as late as early June!
While frost may look pretty, when it comes to tender annuals and vegetables we always recommend to err on the side of caution; one degree can make a life-altering difference to your gardens! Cold weather, and especially frost, causes the water in a plant’s cells to freeze, leading to severe cell wall damage. Frost-damaged plants can look fine in the morning, but once they start to thaw they’ll scream for help with their limp, blackened, and distorted growth. What a nightmare! Follow these tips to help avoid such horrors and give your outdoor spaces the best start to the growing season:
Watch and Wait: It’s hard to be patient, but when it comes to frost and cold weather we really have no choice. Check your local weather reports daily, both for any frost warnings as well as temperatures below 10°C day or night. You can put tender annuals and vegetable plants outside once the mercury goes above 10°C, but if it drops below that magic number you’ll have to bring everything back inside. Seriously, we cannot stress this enough:
Annuals and Tender Vegetables CANNOT TOLERATE Temperatures Below 10°C!
While You’re Waiting: Keep your plants indoors until we reach that magic line on the thermometer (you know, the one at 10°C). Be sure to give them the light, water, and warmth that they need while they wait out the chill. This also goes for any plants you may have purchased early in the season, since many of us get overly excited/impatient for the gardening season and buy up varieties before they sell out. We do not recommend keeping your plants in a garage or garden shed, unless it’s heated to above 10°C and has great windows for natural light. Keeping your plants outside on a covered porch is also a big and unnecessary risk: rain and snow fall down from the sky but cold air does not, and it will surround your plants and freeze them from all sides. Save yourself the heartache, and keep your plants inside the house.
If You Just Couldn’t Wait: We get it, we all want winter to be over and, sometimes, we can be impulsive when it comes to safely planting outdoors. If you waited until the hard frosts (around -4°C) have passed, you can still save your plants from the light frosts (around 0°C) and cold temperatures by tucking your plants into bed. Grab some old bed sheets, drop cloths, or other linens and drape them gently over your plants, and use stones or pots to anchor them so they don’t blow away; you can also pop overturned pots on your plants. Your garden may look like a haunted cemetery, but at least it’ll be protected from the worst of the chill. Remember to remove all coverings during the day so the plants can get adequate light and warmth. Please note: this method may not save you from extreme exposures, so you may still see damage or stunted growth.
But Wait, What about Water? Yes, sometimes a generous watering can help protect against light frosts, but we never recommend this method since it can so easily backfire. Oh, and you’d have to water as the frost settles (before 5 AM!) to get optimal results – now, doesn’t the option of keeping your plants nice and warm indoors sound so much easier?
So Why Can Plants Handle Frost in the Fall? Simply put, because they’ve older. Young, tender plants with immature roots don’t stand a chance against Mother Nature’s chilly blasts, but come fall they’ve had time to grow and establish a strong root system, not to mention all the outdoor conditioning of being out in the elements. If you’re looking to extend your season, the covering method (you know, with the bed sheets) is the best way to protect your gardens, while bringing your pots and baskets into the house or even the garage is fine for fall. Just remember to put them back outside the next day.