Ornamental sweet potato vines (Ipomoea batatas) have been around since the late 1980’s, but their popularity have soared over the past decade. These sweet potatoes aren’t for the table. The colorful vines thrive in the intense heat of U.S. summers from May through September (zones 5-11).
These easily grown plants work well as a low-growing bedding plant, summer ground cover, weepers in hanging baskets and large containers, or vertically climb with trellis support. Older varieties, like Margarita and Blackie, were almost too vigorous and new introductions come in more color choices and grow more compact. Ornamental sweet potato cuttings will root effortlessly in water or soil.
Colorful foliage
Their colorful foliage is the big show. Ornamental sweet potatoes generally do not flower under normal garden conditions. Small, lavender, trumpet-shaped flowers may form in late summer or fall and are mostly hidden under the foliage.
Ornamental sweet potatoes do best and are most colorful in locations that receive 6 hours or more of direct sunlight. They do grow in shadier locations, but vines are not as vigorous or colorful. Average garden soil, fertility and lots of water is all they need.
Insects to watch for
Sweet potato vine is relatively carefree, there are a few problems to watch out for. Pest problems include the sweet potato looper, a caterpillar that chews holes in the leaves, and the sweet potato whitefly.
Control the looper with occasional applications of an insecticide containing BT, spinosad, a pyrethroid (permethrin, bifenthrin, cyfluthrin and others) or carbaryl (Sevin). Wwhitefly can be managed with Summer Light Oil Spray, bifenthrin (Talstar™or Malathion. Disease issues are minimal.
Newer cultivars
New cultivars display various leaf shapes, growth rates and foliage colors. Some feature shorter stem nodes between the leaves, reduced root size, and more compact habit.
Spotlight series (lime, red, black foliage) new for 2017 from Ball FloraPlant
SolarPower series (black, lime, red foliage) new 2016 from Ball FloraPlant
Sweet Caroline Sweetheart series (light green, red, purple with heart-shaped leaves)
New for 2017 -‘Sweet Caroline Sweetheart Jet Black’ and ‘Sweet Caroline Bewitched Green with Envy’
Sidekick series (black and lime with different leaf shapes) from Syngenta.
Desana series – new colors, leaf shapes and compact types.
Illusion series from Proven Winners feature thread-leaf foliage, more compact and less vigorous. Cultivars include Emerald Lace, Midnight Lace and Garnet Lace. ‘Bewitched After Midnight’ (maple-leaf-shaped, purplish-black foliage) also from Proven Winners
According to Dr. Allen Owings, these 6 cultivars grow much less aggressive:
- Bewitched Green with Envy (more green)
- Solar Power Lime
- Spotlight Lime
- Sweet Georgia Light Green
- Sweet Caroline Light Green
- Bright Ideas Lime
Credit: update of current varieties provided by Dr. Allen Owings, Research Horticulturist at the LSU Trial Gardens in Hammonds, LA.