As we are approaching summer season, I have to warn you about flies congregations in the apex of the roof or at the top of greenhouse glass. The common black flies can be noisy because of the constant buzzing sound that they make. Apart from unappealing appearance, flies can be really disturbing.
Moreover, they can land on your precious Tomatoes and Cucumbers which you will then use for salads. In comparison to tomato bugs, flies don’t harm plants. They decide to accumulate in a greenhouse due to warm and dry conditions suitable for reproduction. That is why it is better to get rid of flies in a greenhouse as they can deposit eggs on your plants.
So, how to get rid of flies in a greenhouse?
First, you would need to clean up decaying organic matter as flies feed on it. Then, keep windows open so they can leave. Lastly, you can install fly traps and grow Carnivorous plants to control flies. For example, North American pitcher plant can be easily grown in a greenhouse.
In this blog post you will learn why are flies congregating inside the roof of the greenhouse. We will also talk about the prevention measures and how to control fly infestation. Let’s dive in!
Step 1 – Clean up dead organic material
Flies breed in animal waste and decaying organic material like fallen leaves, fruits. They can pick up bacteria and viruses from waste and carry them potentially causing human diseases. Female flies deposit eggs in moist organic material where the larvae or maggots develop.
In optimal conditions flies can undergo complete metamorphosis from egg to adult in just 7 days. That is why flies occupy greenhouses in summertime. That is why the best prevention measure is control. When flies are still at larval stage, they are easy to manage.
First, you need to eliminate the habitat for development. You can remove rotting organic material in which the larvae develop. It will break the life cycle of the fly and, as a result, decrease the number of adult flies congregating in a greenhouse.
Step 2 – Install Fly Traps
Don’t reach out for chemical pesticides. Although they can be effective to keep the number of adult flies low for some time, that is not a permanent solution. Flies can rapidly develop resistance to chemical pesticides. Moreover, you don’t want to spray chemicals around your plants.
Instead, make sure to open greenhouse windows so the flies can leave the structure. However, if they prefer to stay, I advise installing sticky fly traps. This one can be secured outside the greenhouse on wire holders. It will not get rid of flies completely but will significantly reduce them in numbers.
Alternatively, if you are looking for an environmentally friendly option, a Reusable Fly catcher is a good buy. You would need to use food bait to lure flies into the cage and they will be trapped inside. Once flies die naturally, you just empty the tray.
Step 3 – Grow Carnivorous plants
Many greenhouse growers swear by using Carnivorous plants. The insect killing plants don’t smell and are easy to grow in a greenhouse or conservatory. To thrive they need acidic growing conditions and lime free water. Don’t water them with tap water as it is going to kill Carnivorous plants.
They actually benefit from watering with rainwater. Tap water is treated with chemicals while rainwater is soft. To find out why rainwater is better for plants read this article. Moreover, that is very economical solution too. You can collect rainwater from the greenhouse roof by installing a simple water catchment system.
How does a pitcher plant catch insects?
At this point you might be wondering how carnivorous plants catch their prey. Well, there are 5 basic trapping mechanisms that insect eating plants use. For example, pitcher plants have pitfall traps which that trap prey in a rolled leaf containing a pool of digestive enzymes or bacteria.
Pitcher plants attract and lure their prey with nectar. It is a passive trap with waxy coating which is slippery for insects causing them to fall into the pitcher. The insects rot down inside the plant and turn into nutrients. These are them absorbed into the plant as essential nutrients for growth.
I would advise to grow at least 3 pitcher plants in a greenhouse. They are safe for children and pets. Go for a North American pitcher plant, also known as Sarracenia, as it needs full direct sun and grows best in unheated greenhouses or conservatories.
If you need more guidance on how to grow pitcher plants, check out this blog post. You will find the information about the Sarracenia species and growing requirements. If you are seriously interested in cultivating Carnivorous plants, The Savage Garden book is a read for you.
Keep in mind that growing Carnivorous plants is not suitable for a greenhouse where you are using biological control. They will catch predators too. For example, not many gardeners don’t know that you actually shouldn’t get rid of spiders. Click here to find out why.
What do you do to get rid of flies in a greenhouse? Share your tricks and tips with fellow gardeners in the comments section below!
Happy Growing!
