Dennise, horse apples (hedge balls) grow on trees, they are green a little larger then a lemon about the the same texture as one also. Ive seen them growing in fields in texas. I find them in the grocery stores in with the produce. They work very well in keeping spiders away. Don't know about spider mites but it is worth a shot. Ask for them in your local grocery store. I live in mn so they don't grow here but can get them.