Summarize the following:
Chrysanthemums contain a chemical component called pyrethrum, which is capable of paralyzing many garden insects. Mix the dried petals and water together in a large stockpot. Place the stockpot on your stove over high heat bring it to a boil. Boiling the mixture releases the pyrethrum into the water. Turn off the heat after 20 minutes. Remove the dried flowers and save the infused water. You can discard the dried flowers or place them in your compost. Use a funnel to transfer the liquid to the bottle. Focus on spraying the most damaged areas before moving on to less damaged areas. Cover the entire plant with solution, including the undersides of leaves. Keep the solution in a cool, dark place, like your cupboard. After 2 months, the solution may no longer be effective, so it's best to throw it out and make a new batch.

Summary:
Combine 1/2 c (113 g) of dried chrysanthemums with 4 c (1 L) of water. Boil the mixture for 20 minutes. Pour the solution through a strainer. Pour the pesticide solution into a spray bottle and treat plants. Store the solution for up to 2 months.