Aphids are the bane of my existence in the garden. Somedays in the garden, I feel I will NEVER win the battle with these little monsters. Have you ever found that they have completely ruined a crop? Sitting with your hands in your head and thinking, I am done! They are WINNING!
Trust me, you are not alone. I decided to understand these little monsters better and stop them in their tracks before they could cause havoc.
So, what is aphids?
Aphids are small sap-sucking insects in the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in colour. The group includes fluffy white woolly aphids. 
The life cycle of the aphid is complicated. An aphid infestation begins when a few winged aphids fly onto a plant and leave behind a few young aphids.
Wingless females, called stem mothers, reproduce without fertilization throughout the summer. These stem mothers are unique in that they produce living young as opposed to eggs, as occurs in most other insects. Eventually, the plant containing the stem mother and her offspring becomes overcrowded, and they move to the next plant.
In late summer, both males and females are produced. After they mate, the female lays eggs that survive the winter. In warm climates, there may be no need for an overwintering egg stage, and continuous generations may occur.
Each female produces hundreds of offspring over several generations. The average lifespan of an aphid is approximately one month. They reach sexual maturity in four to ten days and then are able to produce their own offspring.
Nancy Moran (1992) suggests that in the insect world, the most intricate and varied life cycles are probably found in aphids.
Aphids suck sap from their hosts(plants) and inject a toxin causing plants to wilt, yellow, and often die. Some aphids transmit viruses that cause plant diseases, and they excrete a sticky substance called “honeydew,” upon which a black sooty mold can grow, which diminishes the aesthetic value of the plants. Ants may guard and care for aphids in return for the honeydew (a sweet excretory product) they produce. Ants protect aphids from weather and natural enemies and transfer them from wilted to healthy plants.
If you see misshapen, curling, stunted, or yellowing leaves, be sure to check the undersides; you will probably find aphids there.
The good news is that aphids tend to move rather slowly and, with diligent care, can be controlled.
What to do in the garden for aphid infestations?
- Aphids are small insects that can easily be blown off plants by spraying high-pressure water. The aphids will either be crushed by the water pressure or blown far enough away from the plant that they might not be able to find their way back to it. Water spray is one of the most effective ways of clearing an aphid infestation, but it’s challenging if there’s an aphid infestation on a tree. Keep a spray bottle close to the garden. When walking in the garden, enjoying the beauty, and you see leaves curling in or misshapen, use the spray bottle and spray those little suckers off! This will be very effective with good management and if your infestation is not too bad.
- Ladybugs, lacewings, and parasitic wasps are all-natural predators of aphids and can help keep their populations in check. Ladybugs are perhaps the most well-known beneficial insect for controlling aphids. Flowers like cosmos, calendulas, marigolds, and herbs like coriander, fennel, dill, and yarrow are great for attracting ladybugs and lacewings to the garden.
- Aphids use their sense of smell to detect food, identify members of their own species, and detect predators. You can use this to your advantage by repelling aphids from your garden with scents like capsaicin, peppermint, thyme, rosemary, neem oil, chives, garlic, petunias, marigolds, and mums.
- Make use of companion planting. Aphids are especially attracted to mustard and nasturtium. Plant these near more valuable plants as traps for the aphids. The aphids will likely go for these plants before your prized cabbage. (Check your trap plants regularly to keep aphid populations from jumping to your valued plants.) Nasturtiums spoil the taste of fruit tree sap for aphids and will help keep aphids off of broccoli.
- Aphids are repelled by hot pepper, which contains a chemical called capsaicin. The capsaicin in hot peppers irritates aphids, as they will stay away from plants as a result.Companion planting with hot peppers won’t work, but creating a spray will:
- Bring 8 cups of water to a boil
- Add in 1-2 hot peppers (think cayenne or ghost peppers) chopped
- Reduce the heat and let cook for 15 minutes
- Remove from heat and let the mixture cool completely
- (Optional) Let the mixture steep for an entire day
- Strain the mixture into a spray bottle.
Be careful when spraying your mixture. Don’t spray directly on edible fruits or vegetables. Instead, spray the leaves or stalk of the plant. Be sure to spray a small area first to ensure it doesn’t adversely affect your adored plants!
- If all this fails and your garden is under attack from these little monsters, use pesticides. Pesticides are very effective against aphids, but they must come into contact with the aphids in order to work. Be sure to follow the application instructions provided on the packaging. If I need to use pesticides in the garden, I prefer pesticides from Biogrow. Two products that work fantastic for aphids and do NOT harm bees, lacewings, and ladybirds are Biogrow Neem oil [1] and Biogrow Neudosan. [2]
Aphids become a problem when things get out of balance in the garden. This can happen when drought, poor soil conditions, or overcrowding stress the plants so much that winged aphids are produced. These winged aphids fly off, searching for new plants, repeating the process.
Adding continuous nutrients to your garden, keeping the moisture levels constant, and attracting beneficial insects to your garden are a few preventative measures you can implement.
Aphids can be a real nuisance in the garden, but the battle does not have to be lost! You can win the battle by implementing good gardening principles and being patient while your soil builds up nutrients!
Happy Gardening Friends!