What pests do alliums repel?
The genus includes garlic, chives, leeks and shallots, as well as tall, ornamental varieties like Gladiator and Allium giganteum. These plants emit a natural sulfur-onion aroma that masks the scent of surrounding vegetation, confusing and deterring pests such as aphids, cabbage worms, mosquitoes and slugs. The allium garlic (Allium sativum), like the related onion (Allium cepa), is resistant to slug feeding. The intense smell deters the slimy fellows so much that sometimes even tasty neighboring plants are left alone.