Aphids are tiny insects the size of a pin head. They damage roses and other plants by sucking the sap or juice out of the plant. In addition to damaging or killing your rose bushes, aphids can carry viral diseases. These pesky little bugs multiply rapidly and will completely cover a rose bush. While commercial products are available to help you get rid of aphids, these products typically contain chemicals that can be harmful to the environment. Organic methods are available to help you remove aphids from your roses.
Fill a spray bottle with 1 tbsp dishwashing detergent, 1 tsp vegetable oil and water. Shake the solution to mix before each use. Coat aphid-infested roses with the detergent spray to kill them, repeating the spray after each rain or watering.
Pour 1 gallon of water into an empty milk jug. Place 3 tbsp minced garlic in a cheesecloth and knot the cloth to keep the garlic inside. Steep the garlic in the water for one week to make a garlic tea spray to kill aphids.
Remove the cheesecloth filled with garlic from the milk jug. Pour the garlic tea into an empty spray bottle.
Spray the garlic spray on remaining aphids on your roses. Spray the undersides of leaves and flower petals. Continue to use the garlic and dishwashing detergent sprays for several weeks to ensure that all aphids are removed from your roses.
Aphids have a tendency to congregate on the undersides of leaves and inside young, tender rose buds. You'll also see when aphids are present because ants feed off of a nectar produced by the aphids. Black mould on rose bush foliage and flowers is caused by dripping nectar from aphids. While the black mould itself doesn't hurt your roses, it prevents the sun from getting to that part of the plant.