Potato vine is a vine that is grown as an ornamental for its star-shaped flowers. The flowers emit a sweet scent that attracts birds but drives away deer. The genus name ‘Solanum’ means ‘comforting or soothing’ in English. It bears glossy berry-like fruits that are black, blue, and purple in color.
I. Appearance and Characteristics
Solanum laxum, commonly known as potato vine, potato climber or jasmine nightshade, is an evergreen vine in the family Solanaceae. It is native to South America and commonly grown as an ornamental garden plant.
The jasmine-flowered nightshade is a woody climber that forms branches 2 to 8 m long and has a base that can reach more than 10 centimeters in diameter. Fast-growing, it climbs by winding the leaf stalks around supports. The shoot axes are strongly angled zigzag, hairless or in the youth stage with simple, white, single-row trichomes less than 0.5 millimeters in length. New growth is hairless or finely to sparsely hairy. The bark of older branches is green or reddish green or, if the plant grows in direct sunlight, often purple-green. The ovate or ovate-lanceolate leaves are 30 to 50 mm long and 15 to 25 mm wide. The sympodial units contain many leaves. These are usually simple, only very rarely divided with one to four irregular lobes and pinnately split.
Inflorescences
The white or pale blue flowers appear in groups of around 20 in branched inflorescences, produced in profusion in the spring but also sporadically at other times of the year. The inflorescences are initially terminal, later also laterally. They are hairless, reach lengths of 5 centimeters and more, are usually divided two or three times, but can also be divided significantly more often and contain up to 50 flowers. All flowers are fully developed and five-fold. The inflorescence stalk becomes 0.5 to 4 centimeters long, but its length is very variable depending on the size of the inflorescence and the age.
These are followed by dark blue or black berries that are around 8 mm in diameter.
Solanum laxum is cultivated as an ornamental. The white-flowered cultivar ‘Album’ has received the Royal Horticultural Society’s Award of Garden Merit. It is hardy down to −10 °C (14 °F), but requires a sheltered position in full sun.
The plant is poisonous, causing abdominal pain if ingested. Therefore gloves should be worn when handling any part of the plant.
II. How to Grow and Care
Potato vine is considered easy to maintain, thriving in well-drained soil and requiring moderate watering to prevent root rot. It is essential to provide potato vine with adequate support for climbing, as it is a vigorous grower. Pruning for size control and removal of spent flowers can promote continued blooming and healthy foliage throughout its growing season.
Watering
Originating from regions with moderate climates, potato vine is accustomed to a balance of moisture, thriving in conditions that are neither too wet nor too dry. This climber demonstrates a good tolerance for short periods of drought, making it quite resilient once established. Its watering regimen aligns with this hardiness, requiring hydration once every three weeks. As an evergreen plant often grown outdoors, potato vine’s ability to retain its foliage year-round contributes to a consistent water uptake even during cooler months when other species may go dormant.
Fertilizing
Fertilize potato vine during the growing season with balanced nutrition fertilizers, ideally with slow-release granules to promote consistent nutrient delivery. A monthly application is recommended, adjusting the quantity in line with the product’s guidelines to avoid over-fertilization. This sustains potato vine’s vigorous growth and enhances flowering, particularly in spring and summer. Seasonal variations should guide fertilizing frequency, with reduced applications in winter. Always water potato vine post-fertilization to aid absorption and prevent root burn. Novices and experts should wear gloves and follow package instructions to maintain potato vine’s health and their own safety.
Propagation
Potato vine, a member of the Solanaceae family, is a vigorous climber often favored for its attractive foliage and growth habit. Propagation primarily through cuttings is an effective way to replicate its desirable characteristics. Aim to take healthy, non-flowering shoot tips, making a clean cut below a leaf node. The cuttings should be placed in a well-draining medium and maintained in warm, humid conditions to encourage rooting. Root development is typically observed within a few weeks, after which the new plants can be gradually acclimatized to less controlled environments before transplanting.
Transplanting
The perfect moment to bestow your potato vine with a new home is during the late summer to early fall (S4-S5) – an ideal time as reduced heat pressure allows the plant to acclimate and establish its roots comfortably. When transplanting your potato vine, choose a sunny location with well-draining soil for it to flourish. To make things easier, ensure to water it thoroughly before the move. In its new setting, the enchantment of potato vine will surely be a delight to your landscape!
Overwintering
Potato vine, endemic to South America, thrives naturally in tropical regions, exposing it to less severe winters. The plant’s inherent resilience enables it to weather colder seasons, although frost conditions can challenge its survival. To counter this, winter care involves guarding potato vine against extreme cold, preferably by application of mulch or relocation to a sheltered spot. Pruning back after the first frost ensures sprightly spring regrowth.
III. Uses and Benefits
Potato vine is a fast-growing climbing vine that produces an abundance of fragrant white flowers from summer to fall. Its dark berries add a decorative value, but are toxic and should never be eaten. Because of its vigorous growth, potato vine can quickly cover a sunny wall or a small arbor. Its wiry stems are best tied to a trellis or another convenient support structure.