Animals and Growing Onions

Planting and Care

• Start onions from sets for a jump on harvesting. Plant seeds indoors in February or at least eight to 12 weeks before planting outside. You need to provide a well-drained exterior bed with plenty of organic matter incorporated. A full sun location is preferred. Plant out the starts four inches apart in spring and keep them moderately watered and weeded until fall. Most varieties will be ready for harvest when the tops have fallen over.

Pests

• Onions have several insect pests but no listed animal pests. Most animals steer clear of onions or any other plant in the Allium family. It is not known if this is because of the flavor or the strong odor. Even deer will usually leave the plants alone but may browse the tender tops in early spring if other foods are scarce. Even voles, who often nibble at underground root vegetables, leave the bulbs of onions alone in favor of less pungent plants.

Dogs and Cats

• Onions are toxic to domestic pets. The onions cause a toxic anemia that is worse the more of the vegetable the animal eats. The anemia is called Heinz body anemia and results in weak bubblelike projections in the red blood cells. The red cells rupture and cause anemia similar to what happens with doses of acetaminophen. Cats are more severely affected and it doesn't matter if the onion is cooked or raw, the greens or the bulb.

Repellent

• Onions are a common ingredient in home repellent recipes for both insects and animals. The potent odor may be the cause, and when you combine it with cayenne pepper or other strong flavors, the animals don't come around anymore. Mix a batch of pureed onion, garlic and cayenne with water and pour it into a spray bottle. Spray the periphery of the vegetable garden as a natural pest repellent.