Heather’s Gardening Service

 Essential Tasks to Prepare Your Garden for Winter

Written by Heather Morren

Fall comes fast in Edmonton. While, according to the calendar, Autumn doesn’t officially start until September 22, on average, our first frost day is September 16. That doesn’t mean we may not have some more warm, maybe even sweltering, days ahead but it definitely means that cooler weather is fast approaching. 

Here are some essential tasks, as well as some tips and tricks, to help get your garden cleaned up:

1) Pick your produce

If you read last month’s blog article, you may recall that many of your garden vegetables can withstand frosty temperatures. Produce that grows underground such as carrots, onions, garlic, turnips and kohlrabi will barely be phased by a smattering of frost. 

However, not all crops are as resilient. Beans, peas, tomatoes, and many herbs will not fare as well. If you wish to take full advantage of the food you have grown over the course of the winter, it is best to harvest the fruits of your labor before the temperatures dip below zero.

For more information about frost tolerant plants, be sure to check out my August 2024 blog post Extending Your Harvest: The Top Crops to Sow in August for a Fabulous Fall (or Spring) Harvest 

 Harvesting peas, cucumbers, carrots and beans

2) Cut back or pull dead and dying perennials 

Once you have removed your produce from your plants, the next task is to remove the plants from the soil. This will ensure that you have a clean slate to start your gardening journey next spring. 

Now may also be a good time to start thinking about cutting back your perennials. Dead blooms may be removed from plants and, if you wish, their dried seeds can often be stored for future planting. Some perennials will start to look a bit lackluster. These can be cut back with a pair of pruning shears or secateurs to about 4-6 inches from the ground. 

For a more detailed list of which plants to cut back and when, read my October 2023 blog Overwintering Your Zone ¾ Perennial Garden.

Cutting back spent tiger lilies to a few inches from the ground 

3) Prune (certain) shrubs and trees 

Many perennial shrubs and trees prefer to be pruned in the spring, before they have started to produce leaves while other perennial trees such as apple and cedar trees really struggle if trimmed too late in the season. 

However, there are some shrubs that like to be pruned in the fall. For example, azaleas, rhododendrons, lilacs, hydrangeas and many other flowering shrubs are best pruned after they have bloomed for the season. It is also a good idea to trim dead branches out of your shrubs while you can still tell which ones are dead and which are alive due to the presence of leaves. 

Dwarf lilac before and after a late summer haircut

4) Do a final weeding

It might seem silly to weed before the snow falls but weeding in the fall is another way to set your garden up for early spring success. Ideally, one should do the final weed of the season once the weather has become a lot colder so that new weeds are less likely to pop up again. However, some perennial weeds will continue to grow beneath the unfrozen soil for quite some time so it is best if you can try to remove as much of the root as possible.

Removing common groundsel from a rocky footpath 

5) Add mulch to your garden beds 

Mulch comes in a wide variety of materials. These can include mulches that you see year round such as gravel, bark, pinecones or needles, or rubber. But mulch can also include temporary materials like leaf litter, grass clippings, newspaper cardboard, and straw. Adding temporary mulch on and around your perennial plants can go a long way in helping them to survive sub zero (or thirty) temperatures. The only downside to adding mulch to your garden beds is that you will likely want to remove it in the spring.

Leaf litter and grass clippings added around the base of a daily

Although the weather is still balmy today, don’t let the cold weather creep up on you! Now is the perfect time to start preparing your garden for the winter. 

Photos in this article were taken by Heather Morren. Information was sourced from my personal experience and a wide variety of online resources. Please ask, should you wish to see a full list.