Add to Cart Compare Quick view Mad Farmer Silica Shield Mad Farmer MSRP: Now: $13.95 Was: The Mad Farmer’s Silica Shield is proudly made in the U.S.A., and provides plants with additional levels of Silicon and Potash. Silica Shield is compatible with all nutrients and mediums. Silicon helps to strengthen plant tissue by strengthening... MSRP: Now: $13.95 Was: Add to Cart Compare Quick view Qty in Cart: 0 Quantity: Decrease Quantity: Increase Quantity: Price: MSRP: Now: $13.95 Was: Subtotal: Add to Cart