How To Identify And Get Rid Of Blackflies In Your Garden

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Insects are an occupational hazard for any gardener, but there's one you may want to curtail if their numbers start to get out of hand. Contrary to their nickname, blackflies, aka black bean aphids (Aphis fabae), aren't actually flies at all. Rather, they're dark-bodied aphids that grow to about ¼ of an inch long and feed on plants in the spring and summer by sucking their sap. Most of the time, you don't need to do anything to manage them. Blackflies don't usually do much damage, and are a normal, healthy part of your garden's biodiversity. However, very large populations of blackflies can weaken plants, so you may want to control them if you notice a lot of blackflies in your garden.

If you're unsure if you have aphids, look for sooty mold on the leaves of plants. Blackflies secrete sweet, sticky honeydew after feeding, which then grows the aforementioned dark, fuzzy fungus. Also, if you have an ant problem, then you probably have an aphid problem too. Ants and aphids have a mutually advantageous relationship, wherein the aphids provide honeydew that the ants can eat, and the ants keep predators and parasites away. So if you notice a lot of ants crawling on your trees or shrubs, check higher up in the plant for aphids on the limbs or leaves. Signs of a severe blackfly infestation include yellow or curled leaves, stunted or dead shoots, and poor plant growth. But fortunately, if your garden is overrun by blackflies, there are some easy steps you can take to curtail their numbers.

You can physically remove blackflies by spraying them with water, cutting off areas of your plants that are heavily infested, or even squashing them yourself with your fingers. Neem oil — such as Bonide Captain Jack's 64 oz Neem Max Cold Pressed Neem Oil Spray — majorly impacts a blackfly's appetite, eventually causing them to die. You could also mix soap and water to create your own DIY aphid spray, which will cause the blackflies to dehydrate and die.

Another solution is to introduce predators to your garden that can get rid of the blackflies for you. One delightful way to get rid of blackflies that will also add beauty and charm to your garden is to set up a bird bath or bird feeder to attract birds that love to feast on blackfly pests. (Bonus: You'll get some fun birdwatching out of the arrangement.) If you're considering this method, here's what to look for when buying or building a bird bath. 

You can also introduce ladybugs, which feed on soft-bodied bugs such as aphids, and they're one of several types of insects you may want to keep around in your garden for pest control. You can purchase and release ladybugs and let them do their job or incorporate plants in your landscaping that will attract the ladybugs naturally. There are a number of beautiful plant options that will naturally attract ladybugs, from marigolds and geraniums to herbs such as chives and cilantro, so you can diversify your garden while helping keep it blackfly-free.