Move your plants indoors:
The first thing you should do is to move your plants inside the greenhouse. You should not wait for the right time rather plan ahead and shift fragile plants before the unfavourable weather conditions. The best time to move the plants is last week of October.
Do the trimming:
Sometimes, overhanging limbs and vines become devastating factor for your plants as they stop sunlight which is an essential element for their growth during winter. The best way to provide maximum sunlight is to trim the unwanted limbs of your plants.
Make the greenhouse airtight:
Another thing you should do is to protect plants from cold air. You will have to install an airtight door for this purpose. This will not only stop cold breeze but also control the humidity that can kill your plants. Make sure your door is in good condition and there is no crack from where frost can enter the greenhouse.
Use thermometer to maintain temperature:
You should not let the temperature drop below 40 degrees F. To ensure that, you can use thermometer but make sure that you are monitoring the temperature on a regular basis. You can also use bubble wrap to ensure heat retention. Moreover, this bubble wrap will not stop sunlight from entering in the greenhouse. Keep in mind that low temperature damages or even kills fragile plants.
Supply fresh air:
Transferring plants inside the greenhouse does not mean that you will keep them in an airtight box. This will damage them badly so make sure they are also getting fresh air. Provide sufficient amount of oxygen by opening the vents or door.
Water your plants wisely:
In the winter, you should water your plants only when the soil is dry otherwise this dampness will have a negative effect.