Potato vine

Sun

Full sun for the best flowering; tolerates light partial shade.

Water

Water regularly during establishment. Once established, water deeply during prolonged dry spells; container plants need more frequent watering.

Soil

Well-drained soil of average fertility; tolerates chalk, loam and sandy soils but dislikes waterlogged roots.

Height

15-25 ft (4.5-7.5 m)

Spread

6-10 ft (1.8-3 m)

Flowers

Summer to autumn, often longer in frost-free climates; star-shaped white to pale blue flowers with prominent yellow centres.

Foliage

Slender stems carry glossy green leaves, usually oval or lance-shaped, with occasional lobed leaves. Evergreen in mild climates but partly or fully deciduous after cold weather.

Growth

Fast in warm conditions.

Care needed

Medium

• Pollinators
• Heat tolerant
• Wildlife
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Needs looking after

Pick your zone, country, light and whether you have pets.

1. Planting day

   2 ft (0.6 m)

2. After 1 year

   3 ft (1.1 m)

3. After 2 years

   5 ft (1.5 m)

4. After 3 years

   6 ft (1.8 m)

   full size

About 3 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Toxic

Invasive in

Australia

In the garden

Spreads vigorously: plan to contain it.

Growth rate

Fast

• Provide wires, trellis or another sturdy support, and tie in young shoots as they grow.
• Water deeply through the first growing season, allowing the soil surface to dry slightly between waterings.
• Apply compost around the root zone in spring, keeping it clear of the stems.
• Feed container plants with a balanced liquid fertiliser during active growth, following the label rate.
• In colder areas, grow in a large container and overwinter in a bright, frost-free place.

Pruning. In spring, once the risk of hard frost has passed, remove dead or frost-damaged stems and shorten crowded or overlong shoots to healthy buds. Tie in retained growth and lightly trim wandering shoots during summer.

Early spring

Check for winter damage and prune once hard frosts are unlikely.

Spring

Plant after frost risk has passed, install support and mulch the root zone.

Late spring

Tie new shoots into their support and begin feeding container-grown plants.

Summer

Water during dry weather and redirect shoots before they reach gutters or neighbouring plants.

Autumn

Remove berries where seedlings could escape, and move tender container plants under cover before frost.

Winter

Keep sheltered container plants in bright light and water sparingly without letting the root ball dry completely.

• Train against a sunny, sheltered wall to soften masonry with foliage and pale flowers.
• Cover a pergola or arch for a light floral canopy, keeping vigorous shoots clear of paths.
• Grow on trellis behind lavender and shrub roses in a mild-climate border.
• Use a large container with an obelisk in a sheltered courtyard where winter protection is practical.

Garden styles it suits: Mediterranean, Modern courtyard, Cottage garden, Romantic rose garden, White garden and Coastal.

Plant it with: Lavender, Shrub roses, Rosemary, Catmint and Agapanthus.

Wildlife: Flowers attract bees, including bumblebees that collect pollen from the yellow anthers. Dense growth can provide cover for small birds.

• Frost damage: leaves and stems may blacken after freezing weather; wait until spring to cut back to living wood and provide a more sheltered position.
• Aphids: inspect soft new shoots and wash colonies off with water; use insecticidal soap if needed, following the label.
• Red spider mites: watch for pale speckling and fine webbing, especially under glass; rinse foliage and use an appropriate labelled treatment or predatory mites.
• Poor flowering: move plants into stronger light where possible and avoid excessive nitrogen feeding.

Treat all parts, especially berries and green growth, as poisonous if eaten by people, cats, dogs or horses. Ingestion can cause vomiting, diarrhoea and abdominal pain; larger amounts may cause weakness or neurological signs and can be serious. Keep berries away from children and pets, and seek medical or veterinary advice after ingestion.

Where it spreads. Can escape gardens and smother other vegetation. It is an environmental weed in parts of eastern and southern Australia, including New South Wales and Victoria, and in New Zealand. Check local guidance before planting, keep it out of nearby bushland and remove unwanted seedlings.

• Chilean potato vine (Solanum crispum)

  Usually has deeper violet-blue flowers, larger leaves that are often wavy-edged, and a more shrubby scrambling habit.

• Star jasmine (Trachelospermum jasminoides)

  Has thick, leathery leaves and strongly scented, pinwheel-shaped white flowers without the potato vine's conspicuous yellow anthers.

• Sweet potato vine (Ipomoea batatas)

  Has soft, trailing stems and broad heart-shaped or deeply lobed leaves, often chartreuse or purple; any flowers are funnel-shaped rather than star-shaped.

The common name refers to its potato-like flowers, while the Latin laxum means loose or open, referring to its loose flower clusters.

Propagation. Take softwood cuttings in late spring or semi-ripe cuttings in summer, keeping them humid in a free-draining propagation mix. Rooted layers can also be separated from the parent plant.

Accepted botanical name

Solanum laxum

Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.