Description

General aspect and origins - Solanum rantonnetii is also known as Lycianthes rantonnetii, Paraguay nightshade or blue potato bush. This fast growing and bushy shrub is native to Argentina and Paraguay. It is known for its purple-blue flowers that appear for a long period, during the warm season.
Leaves - This shrub has evergreen leaves that are alternate, simple, entire, oval to lanceolate. They are almost glabrous on the upper side, and hairy on the underside, with slightly wavy margins. They are up to 4 in (10 cm) long.
Flowers - Flowers are .5-1 in (1.25-2.5 cm) in diameter. They are purple-blue, with a yellow center. They are grouped at the leaf axils. This shrub blooms over a long period.
Fruits - Fruits are not edible. They are red and ovoïd small berries.

Culture

This Solanum should be grown in full sun in mild climates. It should prove hardy to winter temperatures down to about 23°F (-5°C).
Some varieties of interest are:

• 'Outremer' which has wider and bluer flowers.
  
• 'Royal Robe' which has slightly scented flowers, with dark purple-blue flowers.
  
• 'Variegata Aurea' which has variegated leaves, as its name suggests.

Soil - This Solanum prefers a light, well-drained and fertile soil.

Propagation

This plant can be propagated by cuttings or by seeds.