Coffee Grounds can be used as an effective and natural short term DIY repellent for ants and other insects such as slugs, snails, and even fleas found on your pets. Citation.
How Does Coffee Grounds Repel Ants & Insects
Coffee Grounds are effective against ants and other insects because they have naturally developed defense mechanisms to protect the coffee plant from being attacked and eaten by pests. They have several mechanisms to deter pests such as:
1- High Acidity: Brewed wet Coffee Grounds are acidic which can damage the exoskeleton for a lot of insects such as ants and fleas.
2- High Levels of Caffeine: Coffee Grounds have a lot of caffeine and caffeine is a natural pesticide. This is because caffeine interferes with the nervous system of many types of insects by reducing enzyme activity. This is why used coffee grounds are effective against slugs and snails
3- High Scent: Used coffee grounds give off a strong odor which can severely disrupt insects such as ants that rely on pheromones and scent for navigation and movement.
How To Use Coffee Grounds to Repel Ants & Insects in Your Home
Coffee grounds work best as a pesticide when the coffee grounds are damp and have been used – meaning they have been brewed in hot water.
This is because high temperatures bring out; the strong coffee odor, the caffeine and the acids from the within the coffee grounds. All of which work to repel and even kill the ants and certain insects.
So the first thing you are gonna need to do is brew your coffee grounds as you would usually do or you can just use your leftover coffee grounds.
Also do not let your coffee grounds dry out, leave them damp. If they do dry out mix them with some hot water before you apply them.
To apply your coffee grounds you can:
1- Create a 2-3 inch wide line of coffee grounds around your house’s foundation and entrances. The line will act as a buffer or wall against ants and other insects preventing them from entering your home.
2- Make a 2 inch line of coffee grounds at the base of your walls in rooms that are susceptible to ants like your kitchen and pantry.
How to Use Coffee Grounds to Repel Ants & Insects in a Garden
For certain crops you can utilize used coffee grounds to act as a pesticides against ants, slugs and snails. To do so you can:
1- Create 2-3 inch wide line of coffee grounds around your garden – this line will help prevent harmful insects from entering.
2- Mix your used coffee grounds to the soil in your garden.
Coffee Grounds works great in your garden not only because it is a pesticide. But also because it helps to promote the growth of certain microorganism that help to add nitrogen compounds that are needed for strong plant growth. Citation.
You should only use coffee grounds for plants that prefer slightly acidic soil. Plants such as azaleas, hydrangeas, blueberries, lilies, radishes and carrots work well with coffee grounds. Whilst certain plants like tomatoes don’t perform well in slightly acidic soils. Citation.
My advice is before you add coffee grounds to your garden do a quick google search to see if your crop can handle slightly acidic soils.
Also coffee grounds will help to deter cats from using your garden as a litter box. This is because cats hate the scent of coffee.
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