#29 – Marloe Scott Wilson, Keep it Green: Notes from Herb Heaven – Pyrethrum
Pyrethrum has been used for more than a century as a natural insecticide. It is grown prolifically in the highlands of Kenya and that country is the largest producer of Pyrethrum in the world. Australia has also become a major producer of this crop, while Tasmania and Uganda now grow this useful daisy. Pyrethrum is a perennial plant with small white, pink and rose, daisy like flowers. When dried, the flowers are ground up into a powder and used as an insecticide.
Pyrethrum grows to a height of about 60cm and likes a temperate climate. Grows in full sun in well-drained alkaline soil. Propagation is by seed, or splitting parent plants. Pyrethrum is harmless to all warm-blooded animals including human beings. Dried flowers or powder can be sprinkled outdoors and indoors to repel flies, ants, cockroaches and bedbugs. If used carefully on animals, it is effective for the control of fleas and lice. Avoid harming useful insects by spraying at dusk – it decomposes overnight. Pyrethrum makes a beautiful border plant and cut flower.
You can also try steeping 2 tablespoons of the dried flowers in hot soapy water for an hour, leave to cool, then strain and dilute to use as a spray. Remember to do this in the late afternoon so that the ladybirds, bees and butterflies can get home first!
Organic insecticide
Grind up dried pyrethrum flowers to a powder
Steep the powder in enough paraffin,
rubbing alcohol or methylated spirits to cover.
Let it stand for 24 hours.
Filter and store for up to 6 months.
Dilute 10 times in water before using.
For more information on Marloe Scott Wilson and Keep it Green visit her website: