It is often assumed that anything labeled organic or natural will be good for the garden, but a new book from author Jeff Gillman aims to shed a little light on a few organic gardening myths.

Jeff Gillman teaches horticulture at the University of Minnesota and has investigated the science behind many popular organic techniques. In his new book, The Truth About Organic Gardening, he confirms many long-held beliefs about organic benefits, while puncturing more than a few common myths, in an effort to help gardeners and weekend farmers get the best results for their gardens, while cutting through the greenwash.

Jeff Gillman states, “Gardeners tend to assume that any product or practice labeled as organic is automatically safe for humans and beneficial to the environment. This is not universally true, and the exceptions can pose a significant threat to human health. I wrote my book to help people see beyond dogma and into the truth behind different gardening practices, organic or otherwise."

For any budding gardeners out there, a few of his tips are below:

True or false? Garlic not only repels vampires, it also repels whiteflies, aphids, and beetles.
A: True. Sprays made from garlic extract and water repel a variety of insect pests, as long as the spray reaches every part of the plant you want to protect.

True or false? Manure is always a desirable soil amendment.
A: False. Composted manure is a wonderful addition to the soil. Fresh manure shouldn't be used because it can release ammonia, which can injure plants. Fresh animal manure can also contain weed seeds and human pathogens. E. coli can live in uncomposted manure for up to 21 months.

True or false: Praying mantises are useful for controlling insect pests in the garden.
A: False. Mantises do not eat enough to effectively control harmful insects.