Bay leaves are the most efficient and natural cockroaches repellent. Both, dry or fresh bay leaves can be used as cockroach repellent, but still crushed dry leaves in a powder form are most efficient as they release much stronger smell.
Insect Repellent: Bay leaves are a great insect repellent as they contain lauric acid. A dish of bay leaves will ward off insects. A paste made from crushed leaves and little oil relieves stings and bites when applied topically.