“ By installing a humidifier in a greenhouse or indoor garden , most growers can achieve a higher ambient humidity and provide suitable atmospheric conditions for establishing a predatory mite population .”
Atmospheric Conditions
One advantage of indoor horticulture and greenhouse gardening is the heightened control over atmospheric conditions . Growers rely on air conditioners , humidifiers , heaters , and fans to control both the temperature and humidity . Just as the plants themselves have specific atmospheric conditions for optimal growth , many beneficial insects have a particular humidity and temperature range in which they will thrive . A good example of this is predatory mites . Predatory mites can be a great control method for spider mites . However , keeping the humidity level high enough for mite predators to become established may be difficult for some indoor horticulturists . Although some predatory mite species survive in humidity ranges of 45-90 per cent , most will establish best in humidity ranges above 60 per cent . By installing a humidifier in a greenhouse or indoor garden , most growers can achieve a higher ambient humidity and provide suitable atmospheric conditions for establishing a predatory mite population . However , this should be done with caution during the later stages of fruiting and flowering when the garden is prone to humidity-related issues such as mold or rot .
A grower may want to combine two or more beneficial bugs as a defense against pest insects . She should try to match the beneficial predatory insect ’ s preferred atmospheric conditions with the required atmospheric conditions for that particular stage of growth . Horticulturists can cover their bases when the atmospheric requirements of the garden change ( e . g . when the plants are moved from vegetative growth to flowering ). For example , combining the use of predatory mites ( when the humidity can be kept higher ) with a predatory midge , such as feltiella acarisuga ( when the humidity levels must be kept lower ), can be the answer to spider mite control in both high and low humidity conditions . Put another way , matching a beneficial predatory insect to the atmospheric conditions of the garden , depending on the stage of growth , will help with the establishment of a beneficial predatory insect population . Temperature is another factor that affects the establishment of a beneficial predatory insect population . Many beneficial insects , for example green lacewings , are sold in egg or larvae form and need temperatures to reach a certain level to hatch or become active . Many greenhouse growers do not consider the possibility of large temperature swings from daytime to nighttime . During the day , the temperature range might be ideal for the eggs to hatch or for the larvae to become active . However , a drastic drop to colder temperatures during the night could hinder the hatching or establishment of some beneficial insects . A variance in temperature of no more than 15 ° F is the most conducive to a wide variety of beneficial predatory insects . Some predatory insects will not hatch until their eggs experience warm weather for a certain length of time . Praying mantis eggs are a good example of this . They will only hatch after two to eight weeks of consistently warm weather .
50 Maximum Yield