Ornamental · Convolvulaceae
Ornamental Sweet Potato Vine
Ipomoea batatas
Give it sun, warmth, and steady water, and this vine spills color over beds and pots all summer.
Full sun
Every 2–5 days
50–95°F · 10–35°C
USDA 9–11
Overview
Ornamental sweet potato vine is grown for its leaves, not its roots. It is the same species as the food crop, Ipomoea batatas, bred instead for bold foliage in shades from chartreuse to near-black purple. Set it in a bed or a container and it pours over the edges fast, knitting a low carpet of color.
This is a warm-weather plant with no tolerance for frost. It thrives across hardiness zones 9 to 11 and gets grown as an annual everywhere colder, leafing out quickly once the soil warms and dying back at the first hard cold. A single plant can stretch 8 to 10 feet (2.4 to 3 m) wide while staying just inches tall, which makes it a natural for spilling over walls and pot rims.
It asks for little. Give it sun, warm soil, and water that doesn't run dry, and it grows so freely that the main job becomes trimming it back. The vine flowers only now and then, with pale pink to violet funnels, but the foliage is the whole point.
Care
The short version: full sun to a little shade, evenly moist soil rich in organic matter, and warmth above frost. Feed it through the season, trim it whenever it overruns its space, and treat it as an annual where winters bite.
Light
Plant it in full sun for the deepest leaf color, though it takes partial shade without complaint. The dark-leaved kinds hold their color best with plenty of light; in shade they lean greener.
Water
Keep the soil evenly moist and it grows hard, but once established the vine shrugs off a dry spell. Containers dry out fastest and will wilt as a clear watering cue, so check pots in full sun every couple of days through summer.
Soil
Give it loamy, well-draining soil worked full of organic matter. A slightly acidic pH of 5.5 to 6.5 suits it, and the good drainage keeps the roots from sitting wet.
Temperature
It runs best in the warmth between 50°F and 95°F (10°C to 35°C) and stalls in the cold. Frost kills it outright, so there's no leaving it out through a freeze.
Humidity
Average outdoor humidity is plenty and there's no number to hit. The vine handles muggy summer air fine, though good airflow helps keep leaf fungus from settling in.
Feeding
Feed every two weeks through the growing season with a balanced water-soluble fertilizer to keep the foliage coming. A high-phosphorus starter at transplanting gives new plants a strong push.
Pruning
Trim the vines anytime in the growing season to rein in the spread and keep beds or pots tidy. It takes a hard cutback in stride and bounces right back, so don't be shy with the shears.
Size & spacing
Expect a low mound just 6 to 12 inches (15 to 30 cm) tall that sprawls 8 to 10 feet (2.4 to 3 m) wide. Give it room to run or plan to trim, because one plant covers a lot of ground in a season.
When to plant
This vine waits on warmth and dies at the first frost. Start tubers or cuttings indoors a few weeks before the last frost, set the plants out once the soil has warmed in late spring, and let them run until cold weather ends the season.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Not typically started from seed; start tubers or root stem cuttings indoors 4 to 6 weeks before the last frost.
- Plant: Set out plants after all danger of frost has passed and soil has warmed in late spring.
- Harvest: Grown for foliage; rarely flowers (pale pink to violet funnel-shaped blooms). Tubers can be dug in fall before first frost.
Hardiness
USDA hardiness zones: 9–11
Temperature: down to -7°C
Troubleshooting
Trouble with this vine shows up on the leaves first, whether from thirst, a fungus, or something chewing on it. Most of it is cosmetic and easy to head off. Match what you see below and act before it spreads.
Spots and blotches spreading across the leaves
These are fungal leaf diseases, and they get worse when the plant goes back into the same ground year after year. Crowded, humid foliage gives the spores a foothold. Strip off the marked leaves, open the planting up so air can move through it, and move the plant to a fresh spot next season.
Fix:
- Remove and discard affected foliage
- Improve air circulation and avoid overhead watering
Leaves going limp on a hot afternoon
This is drought stress, not disease, and it shows up fastest in pots that bake in full sun. The plant is using water faster than the soil can supply it. Water deeply until it runs from the drainage holes, and step up how often you water containers through the hottest stretch of summer.
Fix:
- Water thoroughly until it drains from the bottom
- Increase watering frequency for containers in full sun
Ragged holes and stippling chewed into the leaves
Flea beetles, thrips, and slugs all graze on this vine and leave the foliage looking tattered. Watch for tiny jumping beetles, dusty stippling from thrips, or the slime trails slugs leave behind. Hand-pick or trap the slugs and keep on top of the beetles and thrips, and clear away the leaf litter that gives all three a place to hide.
Fix:
- Hand-pick or trap slugs
- Monitor and treat flea beetle and thrips populations as needed
Toxicity
Good news for pet owners: this vine is safe. The ASPCA lists Ipomoea batatas as non-toxic to cats, dogs, and horses, and it poses no threat to rabbits, livestock, birds, or people. The tubers are even edible, just blander than the kinds grown for eating.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Safe around cats. The ASPCA lists Ipomoea batatas as non-toxic, so a curious nibble won't poison them.
Dogs None
No toxic compounds here, and the ASPCA clears it for dogs. A dog that chews a trailing vine is fine.
Horses None
Horses can graze near it without harm, since the ASPCA rates the plant non-toxic to them.
Rabbits Safe
Nothing in the leaves or stems threatens rabbits, so a stray bite causes no trouble.
Livestock Safe
Cattle, goats, and sheep can be around the foliage without risk; it carries none of the toxins that worry farmers.
Birds Safe
Pet and backyard birds are in the clear. The plant holds no compounds that would harm them.
People Safe
Harmless to handle and grow around children. The tubers are even edible, just less tasty than the kinds bred for the kitchen.
Varieties
Most of the choice comes down to leaf color and shape. These are the cultivars you'll run into most often.
Blackie
Carries deeply lobed leaves in a purple so dark it reads as near-black across the bed.
Margarita
Lights up a planting with bright chartreuse-green heart-shaped foliage.
Sweet Caroline Group
Comes in green, red, or dark purple with either divided or heart-shaped leaves, so you can match almost any scheme.
Tricolor
Wears variegated green foliage splashed with pink and white.
How to propagate
This vine multiplies with almost no effort, either from cuttings of a plant you already grow or by splitting its stored tubers in spring.
Stem cuttingsEasy
Take 8 to 10 inch cuttings from vigorously growing terminal or middle vine sections in the warm growing season. · Roots typically develop in about 4 to 5 weeks.
Cuttings are the easy way to multiply this vine. In the warmth of the growing season, snip 8 to 10 inch pieces from the tips or middle of a healthy vine and stand them in water or moist soil, where roots form in about 4 to 5 weeks. Wait until frost has passed before planting the rooted cuttings outside.
DivisionEasy
In spring after last frost, divide stored tubers into sections. · Several weeks to sprout and establish.
You can also split the stored tubers in spring once the last frost is behind you. Cut each tuber so every section keeps at least one eye, then plant the pieces outdoors. They take several weeks to sprout and settle in.
Myths
Sweet potato vine is poisonous to pets because it is a morning glory relative.
The ASPCA lists Ipomoea batatas as non-toxic to cats, dogs, and horses. The toxic-seed worry belongs to the ornamental morning glories, Ipomoea tricolor and I. violacea, whose seeds carry LSA and other indole alkaloids. Sweet potato vine shares the family name, not the danger.
The tubers of ornamental sweet potato vine are inedible.
You can eat the tubers of the ornamental cultivars. They simply taste blander than the kinds bred for the dinner table, so they are grown for their leaves rather than their flavor.