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Scientific: Petunia x hybrida (complex of hybrids: Petunia axillaris, Petunia inflata, and Petunia violacea)
Common: garden petunia
Family: Solanaceae
Origin: Warmer parts of South America such as Brazil

Pronounciation: Pe-TUNE-ya HI-bri-da

Hardiness zones:
Sunset Depends on use
USDA Depends on use

Landscape Use: Bedding plant in mass planting color borders, cool season bedding plant, landscape drive entryways, hanging basket, patio containers, or raised planter beds.

Form & Character: Showy, prostrate, formal, bright and cheerful, used as a cool-season annual in Phoenix.

Growth Habit: Evergreen, herbaceous, short-lived perennial, prostrate and somewhat spreading, occasionally reaching a height of 18 inches.

Foliage/Texture: Leaves are strongly viscid (sticky) green to grayish green, variable size, coarsely pubescent, entire and simple, stems are also viscid and pubescent; medium texture.

Flowers & Fruits: Flowers axillary, solitary, sometimes fragrant, funnel form to double ruffled, and myriads of different flower color patterns ranging from white to even black, solid to striped and blotched; fruit inconspicuous.

Seasonal Color: Depends on use and location, but mostly for flower color during winter and early spring color in central Arizona desert landscapes. In contrast, petunia is a short-lived perennial (up to 3 years), in maritime central and southern California landscapes.

Temperature: Garden petunias thrive within a 40o to 90oF cardinal temperature range. Flower pigmentation (color intensity) is enhanced within its lower temperature range, aka below 60oF.

Light: Partial to full sun, no full shade.

Soil: Garden petunias prefer an evenly moist and rich garden soil with good drainage characteristics; but they will tolerant some soil alkalinity. However, poor soil drainage and/or excessive soil alkalinity will result in foliar nutrient deficiencies including leaf yellowing and stunted and weak growth.

Watering: Petunias needs regular water to maintain an evenly moist soil especially, especially during years when winter desert rains are sparse (such as the dry La Nina winters of 2017-18 and 2020-2021).

Pruning: Older garden petunia plants can be pruned severely to re-encourage vigor, especially in cooler coastal California climates where they are grown as perennial bedding plants.

Propagation: Sexual (seed) or asexual propagation (softwood cuttings and tissue culture) are used for reproduction of unstable hybrids.

Disease and Pests: There are many including snails, cutworms, tobacco budworm, tobacco mosaic virus, rhizoctonia stem rot.

Additional comments: This is a great bedding for mixed borders. Garden petunias are easily bred; there are copious numbers of F1 hybrids with an amazing array of different flower colors. Plant individuals 12-inches apart, but don't over crowd petunia plants as this will cause plants to become leggy. Some garden petunia varieties can sometimes reseed in moist landscape areas. Novel cultivated varieties of different flower colors are released each year. Trailing selections such as 'Surfina' (a cross between the wild petunia, Ruellia humilis and Petunia x hybrida) are heavy bloomers that are more environmentally stress tolerant.