I have a tomato plant in the pot I bought several days ago. It is doing well except a few of the leaves at different levels are getting a little yellow and look slightly droopy. It is in full sun all day and has a FULL watering each day. Now, on one tomato I found a hole with worms in it. I pulled it off and checked the rest of the plant. How to I keep these worms (and pests) off the tomato plant naturally? Thank you for your help so much.