Getting your greenhouse ready for winter could be a matter of just closing the door and walking away, something to worry about next spring. But you will be much better prepared for the next gardening season if you spend a few minutes winterizing the greenhouse now.
Removing all plant residues from the greenhouse is one of the more important tasks, both from a sanitation point of view as well as a preventative measure against weeds, insects, fungi and disease. Plant residue can be put on the compost pile provided it has not been infected with aphids or is diseased.
By the same token, I would not put chickweed on the compost pile unless your compost pile generates enough heat to kill the weed seeds. In my experience, most home compost piles do not generate the heat required to kill chickweed.
All greenhouse equipment should also be washed and disinfected. Cultivating tools, pots, saucers, trays and truss supports for crops should be soaked overnight in a 10 per cent bleach solution and then rinsed.
Clean and disinfect all surfaces if possible. Our greenhouses and benches were constructed with wood; consequently, we relied on the -40° temperatures to do our disinfection. If your greenhouse is made of aluminum, disinfect benches and any place that plants have come into contact with the structure.
Remove and dispose of plastic that may have been used to cover benches, or as growing hills or mulch. Some people tend to cultivate the soil in the greenhouse benches, getting it ready for next year, but our policy has been to leave the soil alone until the following year. Because of the lack of snow cover on the greenhouse benches, the extreme cold would penetrate the soil and would “sterilize” it, thus getting rid of insect eggs and weed seeds.
Another important consideration in greenhouse clean-up is to drain your water lines and garden hoses. I usually roll the hoses up and store them in a dry, protected place.
Any packages of leftover seeds and labels should be brought indoors and stored in a dry, cool place. Even though some seeds and fertilizers can be frozen, it is safer to just bring all of them indoors.
Fertilizers, whether chemical or organic, should be stored in a safe manner, preferably in a dry location out of the reach of children or pets.
These simple end-of-season cleanup steps will ensure that your greenhouse is ready for next year’s crop.