If you still use plastic bags to store your herb, upgrade with the Stink Sack Smell Proof Bag. 

These bags offer the same flexibility and lightness of classic plastic bags, but are durable, smell-proof, waterproof and reusable. They're available in a transparent version for an easy view to your materials, or black for more discreetness.

The pack comes with 10 bags and each measures 4 by 3 inches.