How To Use Castile Soap For Aphids

Gardening is a wonderful and productive hobby. But it can be frustrating to watch the fruits of your labor get destroyed by pests. 

When that happens, you have to make a tough call on whether to use chemical pest sprays in your garden. 

Pure Castile soap spray are one of the basics in a homemade insecticidal soap spray
Dr Bonner Pure Castile soap spray is a basic in insecticidal soap spray | PlantCareToday

On the one hand, no one wants pests ruining their plants. On the other hand, you don’t want to damage crops or make them inedible. 

Thankfully there are natural options available without turning to harsh chemical solutions. Many botanical gardens and horticulturists recommend using castile soap for aphids. 

Before trying it yourself, gather all the information you need.

What Are Aphids?

The aphid pest is a small, soft-bodied insect that sucks sap and plant juices. It is a common garden pests that reproduce many times a year. 

It is essential to keep an eye out for them regardless of the growing season. They are smaller than an eighth of an inch.

Aphids may be difficult to see unless they cluster together on a plant’s leaves or stems. 

Aphids damage a variety of plants, including shrubs, vegetables, perennials, annuals, and even trees. They typically target stems, buds, and fruit.

In short, they go after softer new growth, as opposed to more established foliage. The old leaves are tougher. 

Keep an eye on any fresh blossoms and buds on your plants. The new growth is where to focus any insecticide spray when you spot aphids.

What Damage Can Aphids Do?

Aphids suck sap and juices from plant stems, leaves, and new growth. 

This causes plant leaves to turn yellow or brown and wither. Over time, aphids will weaken a plant, causing it to stop flourishing or making it grow in a deformed manner. 

The Chicago Botanic Gardens also warn about “honeydew,” a sweet substance aphids excrete. Since honeydew is so sweet, it causes black mold to grow on leaves. 

This fungus is mostly harmless but may cause the plant to have problems with photosynthesis since it coats the leaves.

How To Control Aphids

Knock aphids off plants with a forceful water spray. Try this in the morning or when you typically water your plants. 

Doing this in the morning can free plants of aphids. It also allows the sun to burn off any insecticide you apply. 

If aphids completely cover a plant stem, some gardeners prune the whole branch off. This is their attempt to get rid of the aphids without risking the entire plant. 

Some insects feed on aphids, like ladybugs or lacewings. These bugs can be purchased for use in the garden. 

Some growers use pesticides that can be very harsh. Castile soap insecticide spray is a preferred natural alternative.

Castile Soap Solution As A Natural Insecticide

Since aphids have soft bodies, you don’t need to use anything harsh to permeate their tough exteriors. This is excellent news in terms of pest control. Castile allows you to get rid of the bugs without harming your plants! 

Dawn soap and castile soap is gentler than regular dish detergents. Many soaps are harsh enough to clean food off of dishes.

Castile soap is affordable for making small or large batches of the natural insecticidal soap spray. For a small batch mix:

  • 1 tablespoon of castile soap
  • 1 quart of warm water

For a large batch mix:

  • 5 tablespoons of castile soap
  • 1 gallon of water 

Adding vegetable oil helps the spray adhere to leaves and discourage aphids from returning. 

Use half a tablespoon of cooking oil in the small-batch or two tablespoons in the large batch.

Keep the homemade insecticidal soap mixture in a labeled spray bottle because you will need to reapply it to plants every few days. 

Only spray plants when you see aphids clustering on leaves or new growth. The liquid soap damages the outer membrane of soft-bodied insects, and they become dehydrated.

Use Castile Soap Spray Carefully

It is best to use castile liquid soap on aphids at the end of the day when plants are no longer in direct sunlight. 

Some botanical gardens say this is because the soap will dry out before it is useful. Others claim that the sun causes the soap to burn and damage the plants’ new growth.

Spray the aphid clusters directly. The castile dish soap mixture also harms other insects. This includes beneficial bugs like honey bees and ladybugs. 

Any remaining residue on the plants will not harm humans if you are spraying crops you can eat.

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