A popular group of free flowering tender annuals with colourful trumpet-shaped flowers. Petunias make excellent container plants, flowering profusely from early summer right up until the first frosts in autumn.
Family: Solanaceae (Potato family)
Botanical Name: Petunia
Foliage: Light-green, simple, oval-shaped leaves on sticky stems.
Flowers: Showy funnel-shaped flowers, available in a range of bright colours, in both single and double forms. Bicolour, spotted and striped forms are available.
Flowering Period: May to October.
Soil: Free draining, moderately fertile soil (sand or loam). Acid, alkaline or neutral pH. Dislikes prolonged wet weather.
Conditions: Best in full sun but will tolerate light shade. Grow in a west or south facing aspect, in a sheltered location.
Habit: Bushy or trailing.
Type: Half-hardy Annual.
Origin: North and South America.
Hardiness: Tender in the UK. Protect from frost.
Plant in a sunny, sheltered position, in a light moderately fertile, well-drained soil or compost. Space 9in (23cm) apart. Do not plant outside until all danger of frost has passed in your area.
Petunias are good performers and deal for growing in tubs, hanging baskets and containers. Some of the new hardier varieties are also suitable for the border.
They can be grown from seed, however it is much easier to buy plants from a garden centre or nursery in the spring.
Water regularly during dry weather and water container grown plants daily.
Pinch out the growing tips of young plants to encourage bushier growth.
To improve flowering, apply an all-purpose flowering plant food (slightly higher in phosphorus and potassium) every few weeks, or use a slow release form. Do not over fertilize.
Dead-head regularly to extend the flowering period and trim back the stems if they become too straggly.
Pull up and discard plants on the compost heap at the end of the flowering season.
Susceptible to attack by aphids. Can be affected by viral diseases and cucumber mosaic virus.
Sow seeds under glass in trays of compost in February at a temperature of 15°C/59°F. Prick out, pot on and harden-off before planting outside in late spring or early summer, after the frosts have gone.
Most F1 hybrids and cultivars sold as bedding plants in garden centres (or online as plug plants) produce excellent flowering plants, with good uniformity of colour, high floriferousness and weather resistance. Flowers come in shades of pink, purple, red, white, blue or yellow. They can be frilled, plain, spotted, striped and bordered.
Petunia 'Amore Queen of Hearts' bears a blend of Strawberry and Jersey Cream bicoloured flowers, perfect for baskets and patio tubs. Height and trails up to 12in (30cm). For sale at You Garden.
Petunia 'Baby Doll' produces masses of bright pink blooms speckled with white spots, throughout the summer. For sale at You Garden.
Petunia 'Colour Parade' (F1 Hybrid) produces a wide rainbow mixture of large flowered blooms. Some clear, some pure colours, others with white stars, some picotee edged in white and others with darker veins and soft radiating centres. Height: 9-12in (22-30cm). For sale at Thompson & Morgan.
Petunia 'Crazytunia Black Mamba' bears eye-catching velvety purple-black blooms on compact, well branched plants. For sale at Thompson & Morgan.
Petunia Duo Mixed has double, Carnation-like blooms in a range of pinks, purples, whites, reds and blues, all summer long. Good weather-resistance. For sale at You Garden.
Petunia Fantasia Mix (Frenzy Series) is an upright variety in a good mix of colours. For sale at Crocus.
Petunia Frenzy Mixed produces a gorgeous mix of colourful velvety flowers. Compact and easy to manage, ideal for patio pots, or flower borders. For sale at Van Meuwen.
Petunia 'Frills & Spills™ series' bears spectacular double blooms in a range of bold colours and sweet fragrance. High-quality, weather-proof plants with a cascading habit for baskets and window boxes. For sale at Thompson & Morgan.
Petunia 'Indian Summer' a unique trailing form that produces masses of blooms that change colour, from golden orange through to pink, and then sometimes back again! Trailing to 40cm. For sale at Van Meuwen.
Petunia 'LightningSky' produces distinctive two-tone purple/white blooms. For sale at Crocus.
Petunia 'Night Sky' one of the best new petunia introductions, with a speckled pattern of white flecks against deep indigo. Awarded an RHS Award of Garden Merit. For sale at Van Meuwen.
Petunia 'Orchid Flowered Mix' produces a mix of double blooms, with magnificent orchid-like, ruffled petals in a selection of vivid colours. Early flowering. Height to 12in (30cm). For sale at Van Meuwen.
Petunia Peppy Blue (Peppy Series) bears purple and white striped flowers all through summer. For sale at Crocus.
Petunia 'Orchid Picotee Mixed' (F1 Hybrid) an outstanding petunia, producing masses of lavish double blooms with crisp, white picotee edges. Height and spread: 12in (30cm). For sale at Thompson & Morgan.
Petunia Potunia Dark Red (Potunia Series) bears stunning deep red velvety blooms display in summer. For sale at Crocus.
Petunia 'Sweetunia Suzie Storm' bears velvety flowers in rich and striking colours with deep purple centres, offset by dark pink bands. For sale at Van Meuwen.
Petunia 'Trailing Kabloom Mix' is a variety of vibrant mini petunias or Calibrachoas. Ideal for baskets or large containers. For sale at You Garden.
Petunia 'Tumbelina Series' is an outstanding trailing petunia with ruffled double blooms. Ideal for window boxes, containers and flower pouches. Height: 10in (25cm). spread: 14in (35cm). Available in blue, pink, magenta, white or as dual-toned flowers. For sale at Van Meuwen.
Petunia 'Wave Mix' a multi-purpose petunia in mixed colours. Ideal in the border or in hanging baskets. Weather resistant in heat or wet periods. Height 18in (45cm). For sale at You Garden.