Petunias can tolerate relatively harsh conditions and hot climates. They need at least five hours of sunlight every day and flourish in moist soil and conditions of low atmospheric humidity. They are best grown from seed. Watering once a week should be sufficient in most regions. Hanging baskets and other containers need more frequent watering. Maximum growth occurs in late spring. Applying fertilizer monthly or weekly, depending on the variety, will help the plant grow quickly. Petunias can be cultivated in hanging baskets.

In horticulture many terms are used to denote different types of cultivated petunias. These include Grandiflora, Multiflora, Wave (Spreading), Supertunia, Cascadia, and Surfinia.