Preparing the greenhouse for winter is as important as preparing the garden. However, it still is different. If you have been following our blog, you will know that we have a Geodesic Dome greenhouse that we built ourselves. There are many ways to prepare the greenhouse, here we share our way.
Harvest the greenhouse
We harvest the greenhouse throughout the whole growing season, often starting with early peas and finishing up with figs and strawberries. But before the season is over, we want to harvest all the tomatoes and peppers.
For us, this means before the fall temperature drops to -10C (14F). That’s when the water starts to freeze in the water tank and the greenhouse growing season is over.
At this point, we often still have quite a few green tomatoes, peppers and other goodies that are all harvested. Green tomatoes ripen nicely indoors.
Empty the greenhouse
Take out all the annual plants in the greenhouse, tomatoes, cucumbers etc, also pots, heaters and what else might have found its way into the greenhouse.
Note, we do not recommend cleaning out the garden completely before winter. In the garden, we usually only take out plants like cabbage that create a big smelly mess. We do leave perennials, sunflowers etc for insects to hide in.
Not so in the greenhouse. There is seldom a good balance of insects in a greenhouse environment, we find it is better to clean it out and have a clean fresh start each spring.
If you have chickens, let them scratch in the greenhouse at the end of the season.
We also remove all the pathway stones, to ensure there aren’t any nesting insects.
Clean the greenhouse
When the greenhouse is empty, we take a garden house and wash the whole greenhouse from top to bottom clean.
The car radiator and fan, that are part of our heating and cooling system for the greenhouse, also need a good clean. It is amazing how many things can build up there.
We not only wash the cover and structure, but we also wash the soil so to speak. We want to wash off excess minerals, that have built up, imitating a good soaking fall rain in the greenhouse.
All of this cleaning and washing uses a lot of water, taking care of emptying the water tank. Last we clean the water tank itself.
Cover the soil
Now that the greenhouse is clean we like the soil to be covered with new mulch. We use compost or wood chips for that.
The mulch protects the soil and also helps to build up the soil. In spring the greenhouse soil is nice and soft and ready to be planted.
Using the greenhouse in the winter
We have been asked if we can grow anything during the winter months in our geodesic dome greenhouse. We are in Zone 3, meaning the temperature can drop to -40 degrees. That is too cold for a simple greenhouse structure. Instead, we have a growing room indoors for the winter garden.
We do like to start growing in the greenhouse as early as March, all depending on the weather of course.
Could we take off the cover, since we do not grow anything in there? Yes, we could, but it would be quite a bit of extra work. Plus we do like the empty greenhouse for storage in the winter for garden furniture.