Valerie from Fort Lauderdale writes
I grow milkweed for Monarchs and have parsley for the Swallowtails.
Bifen Granules should not affect the butterflies as long as they do not land on the soil/areas treated with it. Though it is a non-selective insecticide which means that any insect that is contacted with the insecticide will be killed. You can help limit this effect by only applying the product when bees and butterflies are not currently visiting the area that needs to be treated.
Answer last updated on: 06/03/2014