How to Grow & Care for Petunias: Planting, Feeding & Bloom-Boosting Tips

Plant type:

Tender perennial, typically grown as an annual

Zones:

9-11

Exposure:

Full sun, 6-8 hours daily

Bloom time:

Late spring until frost

Height/spread:

6 to 8 inches tall, 12 to 48 inches spread; varies depending on the variety

Flower color and characteristics:

Available in nearly every color, including black; with single or double blooms, ruffled or smooth edges, and patterns from stripes to speckles.

Petunias are often grouped by bloom size and growth habit:

• Grandiflora petunias: Large, showy flowers (up to 5 in.) but more delicate in rain; best for containers and sheltered areas.
• Multiflora petunias: Smaller flowers but very weather-tolerant; great for garden beds and mass plantings.
• Milliflora petunias: Compact plants with miniature, nonstop flowers; perfect for edging and small pots.

For more on the different types of petunias, see our petunia variety guide.

When to plant:

In spring, after all danger of frost has passed.

Where to plant:

Choose a location with full sun. While petunias will tolerate light shade, they'll bloom best in bright conditions.

Soil:

Light, fertile, well-drained, slightly acidic (pH 6.0-6.5) soil is ideal. Amend clay soils with compost or organic matter.

Container planting:

Use a high-quality, free-draining potting mix with slow-release fertilizer. Ensure pots have drain holes.

Grow petunias from seed:

Start seeds indoors 8-10 weeks before the last frost. Petunia seeds are tiny and slow to germinate. Sow seeds on the soil surface and keep moist until germination. Transplant them out once the soil warms up.

Budworm inside a petunia flower. Photo by: Bhupinder Bagga / Shutterstock

Water:

Petunias have shallow roots that dry out quickly. Water in-ground plants deeply 1-3 times per week. Petunias in containers may need daily watering in hot weather.

Fertilizing:

Add a slow-release fertilizer at the time of planting. Fertilize weekly in hot climates (or every 3rd watering in milder climates) with a water-soluble bloom booster during summer. Plants in containers often need more frequent fertilizing because the nutrients get washed out quicker. Avoid high-nitrogen fertilizers; they promote foliage over flowers.

Pruning and deadheading:

The amount of pruning required often depends on the variety you’re growing.

• Traditional grandifloras: Deadhead frequently.
• Self-cleaning and spreading varieties: Occasional deadheading for fuller plants.
• If plants get leggy and have fewer blooms, cut back by up to 1/3; follow with fertilizer for a bloom flush.

For more, see: How to Deadhead Petunias and How to Prune Petunias.

Pests and diseases:

Petunias can be bothered by pests like aphids, thrips, and mites; as well as powdery mildew.

Budworms are the leading cause of sudden bloom loss. The small caterpillars hollow out buds from the inside, so flowers never open. Inspect buds often and treat promptly. See our budworm control guide for petunias.

PETUNIA VARIETIES

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Photo: Proven Winners

Supertunia Vista® Bubblegum® — Buy now from Proven Winners

Rock stars in the landscape, the Vista® series makes a huge visual impact. Bubblegum® forms a thick carpet of pink blooms that will quickly cover any empty, sunny space in the garden. Its stems will easily grow three feet long in a spreading mound.

Height: 12 to 24 inches
Spread: 24 to 36 inches

Photo: Proven Winners

Supertunia® Royal Velvet® — Buy now from Proven Winners

It's easy to see why this is a top seller! Royal Velvet® is heat and drought tolerant and produces an abundance of deep purple flowers that attract hummingbirds and butterflies. Pair with just about any other color in beds, hanging baskets, and containers.

Height: 6 to 12 inches
Spread: 18 to 24 inches

Photo: Proven Winners

Supertunia® Bordeaux™ — Buy now from Proven Winners

The dramatic veining pattern of this purple petunia is unlike any other. This award-winning annual is prized for its vigor and ease—no deadheading required. Grow on its own or pair it with other strong growers like Superbells® Calibrachoa or Superbena® Verbena.

Height: 6 to 12 inches
Spread: 18 to 24 inches

Photo: Proven Winners

Supertunia® Vista® Jazzberry® — Buy now from Proven Winners

Magenta-purple flowers cover this petunia from top to bottom. This petunia has a slightly more mounded habit, is self-cleaning and requires no deadheading. It has quickly becoming a favorite of gardeners everywhere. Perfect for all types of containers, as well as in borders and beds.

Height: 12 to 24 inches
Spread: 24 to 36 inches

"“This extra-vigorous, extra-large petunia forms a glowing magenta purple blanket of blooms that spreads at least 3 feet across and blooms nonstop from spring through fall without deadheading.” — Meet the 2024 National Recipes and Plants of the Year, Heidi Grasman, Garden Crossings

Photo: Proven Winners

Supertunia Mini Vista® Yellow — Buy now from Proven Winners

Perfect for hanging baskets, containers, or sunny landscapes, this vigorous bloomer delivers cheerful yellow flowers from spring to fall. Heat and drought-tolerant, with no deadheading needed, it attracts bees, butterflies, and hummingbirds for a season-long color show.

Height: 6 to 12 inches
Spread: 18 to 24 inches

2025 National Annual of the Year

Photo: Proven Winners

Supertunia® Black Cherry® — Buy now from Proven Winners

This stunning semi-trailing petunia is covered by cherry-red flowers with black accents from spring until frost. Plant in hanging baskets or containers and allow it to spill over the edges. Combine with Supertunia® Bordeaux™ and Supertunia Vista® Fuchsia.

Height:6 to 12 inches
Spread: 24 to 30 inches

Photo: Proven Winners

Supertunia® Saffron Finch™ — Buy now from Proven Winners

The bright yellow blooms contrast beautifully with bold purples, reds, and magentas, but may fade to creamy yellow in hotter regions. It works well in hanging baskets, containers, and as ground cover. This award-winning variety blooms continuously throughout the season and is heat tolerant, with no need for deadheading.

Height: 4 to 12 inches
Spread: 18 to 24 inches

Photo: Proven Winners

Supertunia® Hoopla™ Vivid Orchid™ — Buy now from Proven Winners

This petunia stands out with its purple flowers edged in bright white, maintaining bold, consistent color all season. Unlike other petunias, its blooms look fresh until they drop, avoiding the typical bruised appearance. It offers vigorous growth and a well-branched, mounding habit that's ideal for both container edges and front garden beds.

Height: 4 to 12 inches
Spread: 18 to 24 inches

Photo by: Luisa Fumi / Shutterstock.

Petunia Night Sky®

White speckles on a deep-purple backdrop give this mesmerizing petunia the look of stars twinkling in the night sky. The variance between day and night temperatures causes the luminous white stars to appear in constantly changing configurations.

Height: 10 to 13 inches
Spread: 20 to 30 inches

Photo courtesy: All-America Selections.

Tidal Wave® Silver Petunia

Dazzling silvery white blooms with dark purple centers and delicate purple veining. Even more impressive is the plant’s ability to be used as a hedge, climbing vine, or fast-growing groundcover.

Height: 16 to 22 inches
Width: 30 to 60 inches

Photo courtesy: All-America Selections.

Wave® Carmine Velour

Lauded for its velvety carmine-rose blooms that remain vibrant, come rain or shine. Large flowers, 2- to 3-inches, cover the entire plant, creating a blanket of color that lasts from spring until the first frost.

Height: 6 to 8 inches
Spread: 3 to 4 feet

Petunias are very popular flowers for adding instant color to a garden. They are incredibly versatile and can be used in many ways. Here are some ideas:

• Plant them as colorful additions to seasonal landscape beds
• Grow them individually in hanging baskets and window boxes or along with other strong growers
• Use them in containers as the filler or spiller component
• Plant petunias in masses for a dramatic blanket of color
• Cover bare spots in your garden quickly and prevent weeds

Do deer eat petunias?

Yes, deer do eat petunias, especially when other food is scarce. If deer visit your garden, consider protecting your petunias with repellents or fencing. Learn more on how to protect your garden from deer.

Do rabbits eat petunias?

Yes, rabbits like to eat petunias. If you have rabbits around, protect your petunias with barriers or natural repellents to keep them safe. See more natural ways to protect your garden from rabbits.

Are petunias poisonous to dogs or cats?

Not to worry—petunias are safe for dogs and cats. However, it's always best to discourage them from eating any plants to prevent any possible stomach upset.

Do petunias need full sun?

Petunias love sunshine and grow best in full sun (6-8 hours a day). Planting them in a sunny spot ensures they stay healthy and full of blooms. They can tolerate some shade, but just might have fewer flowers.

Do hummingbirds like petunias?

Yes, the bright colors and funnel-shaped flowers make them appealing to hummingbirds. See more flowers for hummingbirds.

Why did my petunias stop blooming?

Usually due to a lack of sun, nutrients, or budworm damage. See our guide on how to keep your petunias blooming.