A greenhouse climate is its own little ecosystem, entirely dependent upon you. You decide how much water, nutrients, sun and other elements your plants receive. To ensure your indoor garden never misses out, you can automate the process. Commercial growers have been working with automatic systems for years. Now the technology has been standardized and scaled down to suit most greenhouse situations.
It is now possible to select from a range of monitoring systems to create the ideal climate for your greenhouse and the ideal habitat for your plants. Monitors for temperature and humidity are basic. Additional monitors can check on soil moisture and soil acidity.
The temperature in a greenhouse is affected by the ventilation and the amount of sunshine it receives. Greenhouses are designed to trap the heat from the sun. If nobody changed anything, the temperature would keep rising until the sun went down. Temperature can be controlled by opening the door or opening vents in the roof. In extreme cases, air conditioning could be used to bring the temperature down to a more reasonable level.
Temperature control is one of the easiest aspects to automate. It is probably one of the cheapest as well. You can link vents in the roof to a system of rods that open and close the vents in response to the temperature. As a backup, you can also install a greenhouse heater.
The humidity inside a greenhouse is almost always close to the maximum because of the amount of greenery. Leaves naturally perform a process called transpiration, in which they release moisture into the atmosphere from pores in their surfaces. Controls on humidity are similar to those for heat--You can open the door or open some vents.
Humidity is not as easy to control automatically because of the mobility of the air. Air that is constantly on the move does not have a constant level of humidity, so sensors are difficult to calibrate. It is possible, though, to install a dehumidifier that could help reduce the high levels.
In some greenhouses, or parts of greenhouses, it is often necessary to convince the plants that they are in another season. This can involve using extra lights that imitate the sun being lit during early morning and late afternoon hours. It can also involve the use of greenhouse heaters to raise the temperature. These systems can easily be regulated by timers.
Soil pH and Moisture
Adjusting the soil acidity and moisture content is more involved. Probes attached to meters are inserted into the soil to monitor those levels. Automated systems for adjusting the levels can be installed, but on the scale of a backyard greenhouse, it's probably simpler and more efficient to read the info from the meters and adjust the levels manually, as needed.