Some plants in theChrysanthemumgenus contain a chemical that ’s toxic to many insect but substantially less unsafe to mammals , making it an effective and relatively good insect powder . When concentrated , this chemical substance can also function as a mosquito repellant .
Pyrethrum Daisy and Dalmatian Chrysanthemum
Thepyrethrum daisy(Chrysanthemum coccineum),also known as the paint daisy , is a flowering perennial that ’s winter intrepid in U.S. Department of Agriculture plant hardiness zone 3 to 7.Dalmatian chrysanthemum(Chrysanthemum cinerariifolium ) is hardy in USDA zones 5 to 9 . These plants are the source of the natural insect powder , not thehardy garden mum(Chrysanthemum morifolium ) , which is hardy in USDA zona 5 to 9 .
Growing painted daisy or Dalmatian chrysanthemum in your garden may have some modest , ecumenical repellent impression , but the plants ' effectiveness at repelling mosquitoes is keen when its insecticidal chemical substance are extract and used in localize areas .
Pyrethrum and Pyrethrins
Pyrethrum is a naturally occurring chemical substance that has a neurotoxic effect on mosquito and other piano - bodied insect , and pyrethrins are the dynamic ingredients in Dalmatia pyrethrum . The primary effect of pyrethrins is insecticidal , but there is grounds that they have a repellent effect as well . Dalmatian chrysanthemums typically contain more pyrethrins than painted daisies do .
Pyrethrins are often used in commercial pesticides and repellents , but they are different from pyrethroids , which are synthetic insecticides that act much like the innate chemical substance .
Pyrethrum Dust
To make pyrethrum dust , begin by harvest home flowers during juiceless , warm weather when the flower are fully developed . take flowers near the centre of the plant because they contain more pyrethrum than those on the outside of the plant . Hang the flowers upside down to dry for one or two days to concentrate the pyrethrins before squelch the blossom into a fine pulverization .
Sprinkle the dust in region where you wish to repel mosquitoes . Burning the debris bring on roll of tobacco that may also have a wicked effect ; however , this may not be advisable in many context .
Warning
verbatim contact with pyrethrins may induce dermatitis , and inhalant of the substances may induce allergic respiratory reactions or bronchial asthma blast . Ingestion of pyrethrins may also cause toxic reactions in hoi polloi and pets . Exercise caution when using pyrethrins , and limit your exposure as much as possible , particularly if you have allergies or respiratory problems .
Pyrethrum Spray
To make a sprayable pyrethrin extract , soak about 3/4 Panthera uncia of dried flower in 1 1/2 gallon of water for three hours . Spray the selection directly on aerofoil or clothing to repel mosquitoes , but void inhale and ingesting any of it . Pyrethrins are unsound and degrade chop-chop , so use the spray promptly .
