Hi Carol! I haven't grown mint in a long while and although I never had issues with insects on my mint plants, when I've encountered white flies or aphids on other plants, I always use Insecticidal Soap. I purchased Lady Beetles (Lady Bugs) a couple of times over the years, once for white flies and once for aphids. Lady Bugs are a natural predator but whenever I've released them in my garden to eat the pests, they fly away ... so I stick with an Organic Insecticidal Soap that I purchase at my local garden center. I used to find a brand called Safer Insecticidal Soap but now the only one I find is called Garden Safe and it works really well for all types of plant pests.