Instruct: Classify the given Amazon review into positive or negative sentiment.
Query: Yellow leaves turn green

Great product and very economical. I'm let hesitant to feed my plants fertilizer since this product is so affordable. I either put a tsp. in a 2-gallon bucket of water for roots or put it in a pump sprayer for the leaves.My neglected herbs were turning yellow, after I applied this, they turned green and healthy in just a few days. I learned about this product from someone who used it in their nursery.Ferns love, love, love this product.