Melon Aphids: What Are They and How To Control Them

One of life’s great ironies is that gardeners still resort to chemical pesticides to no avail. Yet the organic gardener next door has healthy, pest-free plants.

This is due to the natural or evolved resistance many harmful pests have developed towards chemical pesticides. Beneficial bugs and natural pest predators lack this issue.

As a result, our chemical gardener has effectively paid a lot of money to kill the help and clear the way for an infestation.

Besides armored scale, protected from pesticides by waxy armor, this fact is best illustrated by the dreaded melon aphid.

What are Melon Aphids?

Sometimes referred to as the cotton aphid, melon aphids (Aphis gossypii) come in various shades of green and tend to infest as many as 700 different plants.

Some of these plants that may be in your garden include:

  • Asparagus
  • Aubergine
  • Cantaloupe
  • Citrus
  • Cotton
  • Courgette
  • Cucumber
  • Eggplant
  • Hibiscus
  • Mallow
  • Melon
  • Okra
  • Peppers
  • Pumpkin
  • Squash
  • Strawberry
  • Watermelon

The vast majority of vegetables in your garden, as well as many fruits, can fall prey to this little monster.

Unlike many other species of aphid, melon aphids tend to prefer food crops to ornamentals, so at least your roses are safe.

What Damage Do Melon Aphids Cause?

As with other species of aphid, melon aphids feed off the sap in your plants. You’ll find them hiding on the undersides of leaves while they feast.

They cause the leaves to curl, hindering photosynthesis and may even kill the affected leaves.

Meanwhile, their frass, called honeydew, attracts ants and sooty mold. The ants protect the aphids from predators to enjoy the honeydew.

Melon aphids are also vectors for many other diseases, such as citrus tristeza virus, crinkle, groundnut rosette virus, and several types of mosaic virus.

The amount of agricultural damage caused by this species alone is incredible. They can devastate to some crops, such as watermelons.

Controlling Melon Aphids

Melon aphids are quite resistant to chemical solutions. They may even enjoy a population explosion if you try to use chemical pesticides.

The good news is that natural remedies can be effective.

Natural Predators

Several natural enemies (predators) exist that love feasting on aphids.

These include:

  • Anthocorid bugs
  • Many species of birds
  • Lacewings
  • Ladybugs
  • Midges
  • Parasitic wasps
  • Some spiders
  • Syrphid fly larvae

Before trying to use these garden friends, you’ll first have to ensure no ants are protecting the aphid colony,

Sprinkle some food-grade diatomaceous earth around the base of the plant every few days.

This substance, made from crushed, microscopic diatom fossils, will lacerate the ants’ exoskeletons when they climb over it. The result is they die of dehydration.

Next, import some marigolds or other plants the beneficial insects like to invite and keep them around.

Finally, you can buy many of these bugs online if there’s not a large local population.

Neem Foliar Sprays

Neem oil is safe and non-toxic, meaning you can treat food crops up to 24 hours before harvesting.

To make a foliar spray of neem, first, emulsify some water by adding 1 teaspoon of pure castile soap or Dawn dish soap to a gallon of water.

Next, add 4 teaspoons of clarified hydrophobic neem oil to the emulsified water.

As a general rule, you’ll only need .5% to 1% percent Azadirachtin for foliar sprays. Clarified neem oils will state the percentages after the extraction process on the packaging.

In the morning or late evening (when beneficial bugs are least active), spray the affected plants, making sure to get every nook and cranny,

The neem will suffocate any aphids it comes in contact with, evaporating in 45 minutes to 1 hour without residue.

Reapply every other day for 14 days or until the aphids are gone.

Neem Soil Soak

Conversely, you can add 2 tablespoons of 100% percent cold-pressed raw neem oil to your emulsified water to create a soil Neem soak.

Pour 2 to 4 cups of the mix over your plant’s roots, which will soak the neem up and turn it into a systemic insecticide.

Any bug that bites, pierces, or chews the plant will ingest Azadirachtin, causing infertility, loss of appetite, and stopping nymphs from becoming adults.

It can take a couple of weeks to see the destruction, but it’s worth it, and you can reapply the soaks every 2 to 3 weeks as a preventative.

Rubbing Alcohol

Another tried-and-true remedy is 70% percent rubbing alcohol, which kills on contact.

Do spot treatments with a cotton ball soaked in rubbing alcohol or mix ¼ cup with 1 cup water and use it as a lethal spray.

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