Things to know before using insecticides
Do your homework and make wise choices. All insecticides should be used only when necessary and plant based compounds are safer for people, pets and the environment than chemical ones.
Insecticidal soaps disrupt insect growth. Soaps are most effective when the spray makes direct contact with soft bodied insects and can be a good choice for a lot of plants, people and the environment. Insecticidal soaps will harm both good and bad insects on contact but most breakdown within 24 hours and won’t affect good insects that may appear after spraying. Spray outside if possible, never in direct sunlight and away from ornamentals that may have bees pollinating or food crops, children and pets. Be sure to spray stems, flowers, and both the top and undersides of the leaves. Use this spray if the temperature is less than 90°F (32°C) or more than 40°F (4°C) or leaf damage may occur. If it is too hot, cold or too windy you can use a spray of clear water to knock insects off and wait for a better day. You can also use your bathroom shower. Water on the leaves may burn the leaf. A follow up spray of clear water after a few hours is recommended as these can clog leaf stomata.
Homemade insecticidal soaps from your kitchen are effective when made and used properly.
Commercial sprays can be purchased at your garden store. To be certain you have the right stuff for the right plant, and for safety both before and after use, please read entire product labels carefully.
Some I can recommend are: Safer, Bayer Natria, and Garden Safe Insecticidal soaps with the active ingredient being Potassium Salts of Fatty Acids.
There are sometimes specific warnings not to use a product on a particular plant. e.g. Areca and other palms, ferns and succulents are extremely sensitive to soaps. Do a test on part of a plant the day before a full treatment if unsure. If you see new yellow or brown spots on the leaves after application you should not repeat the procedure.