One of the main advantages of greenhouse growing is protecting plants from pests. Greenhouse structure does a great job in shielding crops from common garden animals like rabbits, voles, woodchucks, deer, chipmunks or squirrels who like to treat themselves to tomato fruits. Besides that, you can still be dealing with pests, so you need to know how to deter them from greenhouse.
Not all of them, but some insects can still make their way to the inside of a greenhouse. The most common sign of insect damage are holes in the plant leaves. Nevertheless, there are beneficial insects that actually feed on the bad bugs.
That is why instead of panicking and looking for a solution to kill these pests, you need to check if they are actually bad for plants. Although not a common thing, but you can see ants in a greenhouse from time to time. So, it is a good or bad to have ants in a greenhouse?
Are ants bad in the greenhouse?
Whether ants are bad or good in the greenhouse depends on a type of ants and if they form colonies. Although ants hardly ever eat plants, when ant colonies form nests, they can disturb plant roots and affect watering. In the greenhouse, a bad thing about ants is that during spring/summer they become active and collect seeds, which leads to poor germination.
However, in warm greenhouses imported species of ants like tiny pharaoh ants and Argentine ants actually eat wireworms, caterpillars and mites, so they are killing common greenhouse pests. At the same time, ants can spread weed seeds. As a general guidance, it is better to prevent ants from entering greenhouse and if you discovered, that they have formed a nest, get rid of them.
How to deter ants from greenhouse?
All of the above methods to deter ants from a greenhouse are based on the same principal – interfering with their ability to follow scent trails left by other ants. That means that smell of white vinegar, coffee, lemon, orange, cucumbers, cinnamon and pepper will keep ants away.
Spray a mix of water and white vinegar around the greenhouse
To keep ants away from a greenhouse and not to kill them, use a solution of equal amounts of water and white vinegar and you will get rid of ants permanently. Ants can’t stand the smell of white vinegar. Pour the mix into a spray bottle and spray it around the perimeter of a greenhouse. Also, apply solution to the frame and spray the doorways.
Spread used coffee grounds around the structure
Another way to stop ants from entering a greenhouse is to spread used coffee grounds around the greenhouse structure. Ants don’t like the strong smell of brewed coffee. However, you need to replace the used coffee grounds every day.
Grow peppermint or place mint tea bags around the structure
Ants can’t stand the smell of peppermint and will avoid it at all costs. You can either grow peppermint along the perimeter of greenhouse structure or place mint tea bags where ants can potentially enter. Moreover, make a solution of 10 drops of essential peppermint oil with 1l of water and spray it twice daily.
Peppermint deters ants because they communicate with each other by scent markings. So a strong mint smell will interrupt the communication. You can also crush dry mint leaves and spread them around the greenhouse or place in the areas where ants are more active.
Use Essential oils – clove, vetiver and tea tree
Mixing a few drops of essential oils with water makes a perfect ant repellent spray. You can use clove, vetiver, tea tree or peppermint essential oils. All you need to do is to fill the clean spray bottle with 1/4 cup of water and add 15 drops of essential oil of your choice.
Many people found it more effective to mix a few drops of each essential oil in a solution. Spray the mix on the area where ants can enter at least twice a day. That way ants will avoid the places that smell of essential oils. However, keep in mind that you need to eliminate source of interest for ants.
Control pests
Ants feed on honeydew. Various insects like mealybugs, scales and aphids produce honeydew. That is why you can sometimes see ant colonies together with aphids on plants. Ants will actually protect aphids from their predators.
That is why you need to control insects infestations first. Sometimes just washing the plants down with water daily will be sufficient to get rid of bugs. Also, ants prefer dry conditions, so regular watering discourages them from entering the greenhouse.
