One of the most beautiful seasons in the Yukon is autumn.
But with that beauty comes the threat of frost. In fact, frost is probably the cause of the beauty.
Frost is also one of the main challenges a gardener in the north has to deal with.
Living this far north we don’t have to deal with the pests that are common to south
ern gardens. In our semi-arid climate, we also don’t have to deal with a lot of the diseases. But frost is a different story.
There are two kinds of frost. An early frost will kill tender plants and it is usually only a few degrees below zero.
A hard frost kills the top growth of even the hardiest plant and may even freeze the top few inches of the soil. It usually happens in later September or early October, while an early frost can hit at anytime in the summer.
Most of us can’t avoid the hard frosts; it’s the early ones we want to prevent from damaging our plants.
The Yukon is made up of many microclimates, some warmer and more protected than others. As with everything, location is important. But there are some things that can be done to extend a season and protect tender plants.
When we situated our vegetable garden, I thought I had placed it in a good location. It’s on a slope that faces west. But it is also at the bottom of a hill.
And anyone who has studied frost patterns will tell you the top of a hill and the bottom are the first places to be hit by frost. Frost settles into depressions on the ground and will follow a valley.
Not only was our garden at the bottom of the hill, it also was at the bottom of a shallow trench. So the frost not only settled on the bottom of the garden, it flowed over the entire area, touching the tender plants as it went.
One of our first years gardening we lost our potatoes in an early frost at the beginning of August.
While discussing this with my mother, she suggested we build a rock wall above the garden, to divert the frost around it.
I don’t know much about building with stone, but we did decide to build a wall of tires there instead. We put an arched wall at the top of the garden and along the lower side as well.
We also planted trees on the windward side to provide shelter from the cool summer winds.
This has changed the microclimate of the garden. It is now a warm, sheltered spot for vegetables to grow. We have even had success with some heat-loving plants such as corn and beans. Although the corn didn’t do so well this year, the broad beans I planted seem to love their location.
Another form of protection is a wall-o-water.
It is a double layer of plastic that holds water around a plant in narrow tubes. As the temperature drops the water won’t cool as quickly as the air and so the plant inside is at a slightly warmer temperature than it would otherwise be.
I have used wall-o-water covers to grow tomatoes when we have had cool wet temperatures all summer.
While gardening in the north is definitely a challenge, sometimes we do win a battle now and then and enjoy the fruits of our labour.