Neem is a naturally occurring pesticide that comes from the seeds of the neem tree (Azadirachta indica). Neem trees are native to tropical forests in Burma, India and Sri Lanka. Within the tree’s native range, it has been used as a botanical insecticide for many hundreds of years. With growing interest in organic and less-toxic pesticide options, neem products have become very easy to find at most garden centers. It may be the first bottle many gardeners now reach for when they have a pest issue.