You want the plants in your greenhouse to thrive. Whether you're using your greenhouse to sprout seeds for your vegetable garden or grow exotic flowers, proper use of your greenhouse will increase your chances of success. Proper use entails controlling the environment in your greenhouse. The elements under your control are temperature, ventilation, irrigation and humidity. By managing these elements, you can create an optimum environment for your plants, which is why you have a greenhouse in the first place.
Closely monitor the temperature in your greenhouse. A consistent temperature range within your greenhouse is an important part of maintaining the best environmental conditions for your plants.
Place a thermometer in a shady part of the greenhouse. Monitor the temperature throughout the day and during weather changes. If the temperature continually drops below the comfort zone for your plants on cloudy days, for example, you need to adjust your ventilation and heating systems to eliminate the loss of heat on those days.
Though you control the environmental conditions within your greenhouse, it is not a sealed structure. Proper use of the ventilation in your greenhouse will give your plants access to fresh air, an important element in their growth.
Use the ceiling vents and your doors to create airflow. On very warm days, open the vents that are windward, and close the opposite vents and keep one door open. This brings in the wind and pulls it down to the plants. If both vents are open, the wind merely slips through.
For cooler days, close the windward vent and open the opposite vent. Keep the door closed. This allows fresh air exchange while maintaining the optimum temperature.
An irrigation system is integral to your greenhouse beds. Though hand watering may seem to give you more control, an irrigation system is more likely to provide moisture in a more efficient manner.
Plants in a greenhouse need less water than in-ground plants or container plants exposed to the elements. Using an irrigation system allows you to control just how much water your plants receive. Setting up separate irrigation systems allows you to control the amount of water different groups of plants receive. Your bed of seedlings may not have the same requirements as those of more established plants.
A misting system will aid in managing the humidity in your greenhouse. Running your misters during the daylight hours will encourage respiration of your plants. You needn't run your misters during the night, however, particularly if the night temperatures in your region take a considerable drop.
The misters shouldn't soak your plants. They should resemble the light misting you may feel in the bathroom after the shower has been turned off for a few minutes but you haven't yet opened the door. This will prevent mold or mildew build-up on plant leaves and in your greenhouse.