One of the main reasons to build geodesic dome greenhouses is so you control what is and isn’t put onto your family’s food. Most commercial greenhouse operators believe that it’s impossible to run a greenhouse without pesticides. Getting these chemicals out of your food is probably why you have or want to build a greenhouse in the first place.
To control insect pests without the use of pesticide, it’s important to choose and populate your dome with predators that eat insects and don’t damage your plants. These mainly include the praying mantis, small lizards and lady bugs.
Preying mantis and small lizards can live indefinitely inside your dome. Both are voracious insect eaters and will help control unwanted pests. Used together, the lizards will also keep your preying mantis population under control should they explode unexpectedly. Though, without sufficient insects to feed them, this is unlikely.
Probably the most popular beneficial insect used in small greenhouses is the lady bug. These bug fighters, as well as the preying mantis, can be ordered by mail from suppliers around the country. The trick to effectively using lady bugs is to put a lot of them into your dome if you have aphids or white flies.
The earlier you can introduce these beneficial insects the better. And you MUST get them in before you have a major infestation. In this case an ounce of prevention is definitely worth a pound of cure. Do not let your greenhouse become over run with pests then expect a few lady bugs or a preying mantis or two to save the day.
And numbers need to be on your side. I think the reason commercial greenhouse growers are unimpressed with biological pest control is that they don’t use enough of them. For example about 1,200 lady bugs would be about right for 8-10 food dome greenhouses. So you can imagine how many would be needed inside a huge commercial installation.
Lady bugs mature in the fall, they then reproduce and die. Lady bug larva look like little crawling insects without wings. They are also predators at this stage of development so having a thriving population of these insects will keep your greenhouse protected year round.
Suppliers usually have them available most any time of year, offering young ones the spring and mature ones in the fall. If you inoculate your greenhouse with them they will reproduce setting up a cycle of protection for your crops.