← Plant Guides

How to Grow Petunia Grandiflora Superbissima Phantom Purple

Wikimedia Commons

Petunia Grandiflora Superbissima Phantom Purple

Petunia × hybrida

flower

This is a large-flowered petunia variety featuring massive, ruffled blooms in deep purple with darker veining and a contrasting lighter throat. The Superbissima series is prized for its oversized, heavily textured flowers that can reach 4-5 inches in diameter. It's a tender annual that produces continuous blooms throughout the growing season with proper care.

When should you plant Petunia Grandiflora Superbissima Phantom Purple in your zone?

Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.

Get my Petunia Grandiflora Superbissima Phantom Purple timeline →

Example Petunia Grandiflora Superbissima Phantom Purple timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Petunia Grandiflora Superbissima Phantom Purple

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Petunia Grandiflora Superbissima Phantom Purple blooms

    Around Jun 6

    ≈ 50 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Petunia Grandiflora Superbissima Phantom Purple dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily; tolerates partial afternoon shade in very hot climates
💧
Water: Keep soil consistently moist but not waterlogged. Water at soil level to keep foliage dry and prevent disease. Water deeply 1-2 times weekly depending on rainfall and temperature; more frequently in hot weather.
📏
Spacing: 12-18 inches
📅
Days to maturity: 50-70 days from transplant to first blooms
🌱
Planting depth: Surface sow or barely cover seeds; do not bury. Press gently into soil. Transplants should be planted at the same depth they were growing in containers.

Soil

Type: Well-draining, fertile loamy soil
pH: 6.0-7.0
Amendments:
Compost peat moss perlite or sand for drainage balanced slow-release fertilizer

Growing Zones

Find your zone →

Thrives in zones 3-11 as an annual; winter-hardy in zones 9-11

3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b

Sign up free to see if Petunia Grandiflora Superbissima Phantom Purple grows in your zone — and get a personalized planting timeline.

Get my Petunia Grandiflora Superbissima Phantom Purple timeline →

Growth Stages

1

Seedling

2-3 weeks

Tiny plants with first true leaves emerging. Very delicate and slow-growing initially.

Maintain high humidity and consistent moisture. Provide bright light (14-16 hours daily under grow lights). Keep temperature around 70-75°F. Do not overwater.

2

Vegetative Growth

3-4 weeks

Plants develop bushy foliage with multiple stems. Leaves are oval and slightly sticky to the touch.

Pinch back growing tips when plants are 4-6 inches tall to encourage branching. Maintain consistent watering and apply balanced fertilizer every 2 weeks. Gradually harden off before transplanting outdoors.

3

Budding

2-3 weeks

Flower buds begin to form at stem tips. Plants become more compact as energy shifts toward flowering.

Continue regular watering and fertilizing. Support stems with stakes if needed for heavy varieties. Reduce nitrogen-heavy fertilizer in favor of phosphorus to promote blooming.

4

Flowering

6-10 weeks (throughout season)

Large, ruffled purple blooms open continuously. Flowers are 4-5 inches across with prominent veining and lighter throat.

Deadhead spent flowers regularly to encourage continuous blooming. Water consistently at soil level. Apply phosphorus-rich fertilizer every 7-10 days. Stake tall varieties for support.

5

Mid-Season Rejuvenation

2-3 weeks recovery

Plants may become leggy or flower production may slow in mid-summer heat.

Cut back stems by one-third in mid-July to rejuvenate growth. Reduce watering slightly during heat waves if plants are wilting, then resume normal watering. This variety tolerates heat better than some petunias.

Companion Planting

Plan your garden →

Plant with:

Calibrachoa Bacopa Sweet alyssum Dusty miller Helichrysum Mandevilla Salvia Verbena

Avoid planting near:

Other petunias in very close proximity (disease spread) Plants requiring consistently dry soil

Common Pests

  • Spray with insecticidal soap, neem oil, or strong water spray. Encourage natural predators like ladybugs.

  • Increase humidity, spray with miticides or neem oil weekly. Remove heavily infested leaves.

  • Use yellow sticky traps, spray with insecticidal soap or neem oil. Vacuum pests directly with a handheld vac.

  • Remove infected plants immediately. Control aphid vectors with pesticides. Choose virus-resistant varieties.

  • and (Botrytis cinerea)

    Maintain good air circulation, water at soil level only. Remove affected foliage. Apply fungicide if severe.

Uses

🏠

Cut flowers and floral arrangements

Household

Superbissima Phantom Purple's massive, ruffled blooms make stunning fresh-cut arrangements. The deep purple color adds sophistication to mixed bouquets and can last up to 10 days in water. [source]

🏠

Container gardens and hanging baskets

Household

This variety is ideal for decorative containers, window boxes, and hanging baskets, where its oversized flowers create dramatic visual impact. Pair with complementary colors for stunning patio and entryway displays. [source]

🎨

Flower pressing and dried arrangements

Craft

The delicate petals of large petunias can be carefully pressed for crafts, bookmarks, and decorative projects. Dried petals also work well in potpourri or for botanical art. [source]

🦋

Pollinator support

Wildlife

Petunias attract bees, butterflies, and hummingbirds, making them valuable for pollinator gardens. The nectar-rich blooms provide essential food sources throughout the growing season. [source]

🍳

Edible garnish (food-safe cultivars)

Culinary

Petunia flowers are edible and can garnish salads and desserts with their striking visual appeal and mild, slightly sweet flavor. Ensure no pesticides or chemical treatments have been used. [source]

Harvest Tips

Petunias are ornamental flowers, not harvested for food. Deadhead spent blooms to extend flowering season. Cut flower stems in early morning for fresh arrangements; blooms last 7-10 days in water. Cut back stems by one-third in mid-summer to encourage fuller growth and renewed flowering.

Fun Facts

  • 🌱 The name 'Petunia' comes from the Portuguese word 'petun,' meaning tobacco plant, to which petunias are botanically related.
  • 🌱 Petunias are susceptible to over 20 different viral diseases, making virus-resistant varieties like Phantom Purple increasingly important in breeding programs.
  • 🌱 The Superbissima series produces flowers that can be up to 5 inches across—among the largest in the petunia world—making them botanical showstoppers compared to standard grandiflora and multiflora types.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Annual Deadhead Full Sun pH Pinch Back Transplant True Leaves
Shop Petunia Grandiflora Superbissima Phantom Purple plants and related plants at Plant Addicts →

Join 30,000 gardeners planning their gardens with LizPlants.

Get your personalized Petunia Grandiflora Superbissima Phantom Purple planting timeline

Tell us your zip code and we'll calculate exactly when to start Petunia Grandiflora Superbissima Phantom Purple seeds, transplant seedlings, and harvest — based on your USDA zone and local frost dates. Includes calendar reminders and printable task lists. Free to start.

Get my Petunia Grandiflora Superbissima Phantom Purple timeline →