Frost Warnings, How to Protect Your Plants

frost warnings

Many locations on the east coast of Canada and the USA have had frost warnings the past few nights with more to come for the next few days. Some annuals tolerate a light frost, others not so much. Of course, the first frost date varies across the globe, sometimes year to year within the same area.

In other words, frost is unpredictable.

You can extend the season on both ends by heeding frost warnings in your weather forecast. In the spring I tend to start my containers early to ensure I get the annuals I want. If a frost warning is issued, I move the containers into my garage, off the (cold) cement floor, for the night in question. The same technique can be used in the fall when a sporadic early frost is in the forecast.

These are ways you can protect your annuals.

Sheets, Towels, Tablecloths, and even Plastic

Beds of annual (those that you have to plant each spring) flowers can be protected with bed sheets, towels, or even tablecloths. I get the cheap tablecloths from a dollar store, the ones with the felt-like backing; they work great. Sticks or stakes can be used to prevent the covering from crushing the plants, and rocks to hold the covering down so they don’t blow in the wind.

Plastic garbage bags work too and often fit right over containers, just ensure they reach right to the ground. And again, use rocks to hold them in place. Or tie something around the base to hold the plastic in place; burlap works well here too. As do large tarps, although they can be heavy but work great on raised beds with tiny seedlings. If plants are taller, simply add stakes around the plants to keep the tarp off them.

Of course, whatever you use will depend on the size of the beds or containers you wish to protect.

Frost Covers

Yes, there is such a thing in garden centers, nurseries, big stores, and even on Amazon. I’ve never tried any of these options, if you have please let me know how you like them!

A Warmer Spot

If you have annuals in pots or still in their nursery containers waiting to be planted, simply move them to a garage or basement for frost warnings. If in an unheated garage, store them on something so they are not on the cement floor. A shelf or even storage bins work well. Then you can move them in and out depending on the weather.

If you have lots, a wheelbarrow or cart works well to transport them back and forth. You could even leave the tender plants in whatever you use in the garage.

My yet-unplanted annual collection stayed in my garage all day yesterday as the temperature here never reached double digits before another frost warning last night.

frost warnings

Don’t Worry About Perennials in Frost Warnings

While annuals will be affected by frost, most perennials will not. Perennials can be planted as soon as the ground is thawed and will survive the temperature fluctuations in spring and fall.

Perennials can overwinter in containers too if you choose plants two zones hardier than what is normally hardy in your area. Otherwise, you can stick them in the ground to overwinter, to use them again the following spring.

November Weather

So far, our November weather has been incredibly beautiful. At least it has been here in eastern Ontario. We are enjoying this fall bonus as it’s not going to last for much longer I hear.

Garden Blooms Still Glorious

With the warmer-than-usual October and November weather, our perennial garden blooms are still hanging in there. A few light touches of frost have killed off some annuals but even many of them still look lovely. These are from the butterfly garden at our local hospice. I have been hesitant to replace the annuals in my containers for fall and winter decor because the annuals still look great.

Yard Work

Home and cottage yard work has actually been quite pleasant with this nice November weather. In fact so pleasant that fall is fast becoming our favourite cottage season. Warm days and evenings with an absence of bugs have been a bonus.

Even though we are missing a few trees, the deciduous (with leaves that fall) ones make for lots of leaves. It takes days to rake and mulch them, then add them to gardens. Every bit we get done this fall means less to rake in the spring!

I’ve also been granted a few extra days to clean up gardens for clients in my gardening business.

Lakeside Sunsets

The extended fall weather means we have been able to enjoy more lakeside sunsets than usual too. I cannot remember enjoying weather like this in November. When the weather is warm, my arthritic bones and joints are keen to stay at the cottage as long as possible.

Even the turkeys have been enjoying the weather (in the trees, third picture) Hopefully, your fall weather has been nice enough too. What bonuses have you experienced with this November weather?

Overwintering Annuals, Take Two

October blooms

A few years ago, I shared my plan to overwinter some frost-tender tropical plants from my outdoor collection. I was not successful with the bougainvillea featured in that post, but I’ve learned a lot since then, mainly from a group of experts on Facebook.

Washing Roots

It is advised (by said experts mentioned above) to shake the outside dirt off of the roots and then to give them a good rinse with a strong jet of water from your hose before bringing the plant inside. This practice loosens the root ball so the roots can stretch out in their new location.

This works especially well on houseplants that need to be repotted to larger pots too. When examining the roots of tender annuals and houseplants, remove any rotted or dead roots.

Prevent Bugs From Overwintering in Your House Too

The last thing you want to welcome into your home for the winter is bugs. Adult bugs and their eggs will come in if you do not treat the plants, soil, and roots that you bring in. I don’t mind the tiny (the size of fruit flies) buggers flying around, but my husband and grandchildren hate them.

There are several ways to eliminate both the adults and eggs. Insecticidal soap or a solution of hydrogen peroxide works well on the plants and soil. Sticky traps will catch adults preventing them from laying any more eggs. These sticky traps also work well on fruit flies.

Tropicals I’m Attempting to Overwinter this Season

This fall I pulled up three tropical plants that I used as the thrillers in containers.

I find it frustrating (and sad) that these beautiful plants are just achieving that mature, settled-in look when frost ruins them in our zone 4 to 5 gardens. This year I decided to remove the thrillers, rinse their roots with water as advised above, spray them several times with insecticidal soap, then bring them inside.

My biggest challenge was finding sunny spots for them to overwinter. My south and east-facing windows were already houseplant-loaded. It took a bit of shuffling to find spots for three (more) large plants.

Hopefully, they survive until I can reuse them in the spring.

Taking Cuttings

I also took more cuttings from fully mature annuals this fall. Like the tropical “thrillers” in the center of my containers, the fillers and spillers were gorgeous this year too. Especially the coleus, which continues to be my favourite annual for containers in shady spots.

They are all set up in perlite on my basement counter; as soon as roots form I will pot the baby plants up so I have a collection to use in spring. For those of you not familiar with perlite, it is a form of volcanic glass with a high water content, used to propagate plants without soil.

Digging up Dahlia Tubers

Another new thing I am trying this year is digging up the dahlia bulbs I planted in the spring. I have always admired dahlias in everyone else’s gardens, so decided to try them myself this year. My granddaughters loved the various colours and shapes that bloomed right up until this past week when our first frost descended on us..

I followed the same guideline with the dahlia tubers as I did for the roots of the other annuals I am overwintering. Digging up and rinsing well with a hose. The difference here is that I had to leave these lying in a single layer on the floor of my garage to dry before storing them in a box in a cool, dark spot.

Overwintering Annuals, Take Two
dahlia tubers

All of my overwintering preparations are complete, now I just have to wait until spring to see how successful I have been. Have you had any success with overwintering frost tender plants?