The tomatillo plant can provide you with its fruit for quite a few weeks during harvest periods but production can be limited and fruits can be damaged if insects are present on the plant. If you have spotted insects on your tomatillo plants, you don't have to throw them out or start over. Some very simple remedies will keep the bugs away from your plants.
On the Plant
You can create your own spray with items that you already have in your home. The spray requires one garlic bulb, one small onion, one quart water, and one tablespoon liquid dish soap. Simply mix all of the items into hot water and steep for one hour. Strain the ingredients through cheesecloth. Pour the mixture into a spray bottle and shake well. Spray the mixture on the plant on both the tops and bottoms of the leaves. Spray once a day until you stop seeing insects.
Around the Plant
If you don't want to spray anything on your tomatillo plants, you can treat the area around the plant. A simple and effective way to do is this to sprinkle Cajun seasoning, found at most stores, around the base of the plant. You can also sprinkle plain cayenne if you cannot find the Cajun seasoning. Sprinkle again after a heavy rain or when you begin to see insects again. The hot pepper smell that comes from these seasonings often drives the bugs away.
If All Else Fails
Another great remedy that seems to work when all else does not is a mixture of liquid soap. In a large bucket, mix one gallon of water with three tablespoons of liquid soap. This makes a one percent soap solution and will need to be poured into a spray bottle and sprayed directly on the tops and bottoms of your plant leaves. The soap solution suffocates the bugs, clearing them off of your tomatillo plant in very little time. This is something you can do again and again without harming the plant because of the low soap concentration.