The dried flower heads are also available, or you can grow your own and dry them. Pyrethrin extract-based insecticides are effective against a wide variety of insects, including soft-bodied insects and chewing and sucking insects such as aphids, leafhoppers, mealybugs, spider mites, stink bugs, scale, thrips, and whiteflies.1
You can make your own pyrethrin insecticide from homegrown pyrethrum daisies. Once the plant is blooming, pick off the full blooms and dry the flower heads in a cool, dark, and dry place. Store the dried flower heads in a tightly sealed, airtight container. They will retain their effectiveness for up to six months if stored in a freezer. Do not pulverize the flowers until you are ready to mix the insecticide.
When you are ready to use them, wear a protective mask and grind up 1 cup of flower heads to a powder, mix the powder with a little liquid soap to increase the spreadability, and combine with enough water to make a sprayable solution. Pour the solution into a spray bottle. Be sure to label the bottle and store it out of reach from any children. Use the solution as you would a commercial insecticide. The strength of homegrown pyrethrin varies, so feel free to experiment with the proportions until you achieve effective insect control.thespruce How to Use and Make Pyrethrin Insecticide