Maintain Proper Spacing and Air Circulation
Crowding plants increases humidity around foliage, creating a perfect breeding ground for fungal pathogens. Space tomatoes at least 18–24 inches apart and peppers 12–18 inches apart. This gives air room to move and helps sun-drying after morning dew.
Good circulation also makes it easier to inspect plants and harvest fruit. I once planted mine too tightly and spent my afternoons hacking back leaves instead of enjoying fresh salsa!