It may be caterpillars who are eating your plants. You must suspect it first. I personally have not got any products from Walmart. My brother also started his growing a year back at that time, he also faced problem like you, his plants were being eaten by caterpillars, he tried various products but nothing worked for his plants Then he called professionals from Pest Control Monroe CT to help him protect his plants. If you wish to choose some products from Walmart, you can check them online, if it does not work, you can also have an advice from the professionals near by you in your area.