Sprawling stems hug the ground beneath densely packed, sometimes colourful leaves, topped by flowers that recall other ipomoeas. Sweet potato (Ipomoea batatas) is grown for tubers full of potassium, vitamin A and antioxidants, cooked like spuds or turned into desserts; give it full sun and 20 to 25 °C, and you lift them in autumn.
| Name | Ipomoea batatas |
|---|---|
| Family | Convolvulaceae |
| Type | annual tuber plant |
| Height | 8 inches (roughly 20 cm) |
| Exposure | sun |
| Soil | rich, light, and well-draining |
| Bloom | from midsummer to early autumn |
| Harvest | early autumn and mid-autumn |
This plant, part of the Convolvulaceae family (just like bindweed), grows low to the ground, boasts densely packed, occasionally colorful leaves, and flowers that remind us of other ipomoea species.
Discover how to cultivate this veggie with sprawling stems; you can harvest its tubers in early autumn and mid-autumn.
A perennial in tropical areas, from which it originates, the sweet potato grows as an annual in our latitudes.
You don’t sow sweet potato; you plant it like regular potato, straight from another tuber.
Sweet potato thrives in deep, humus-rich soil that’s permeable, well-draining, and on the light side.
It absolutely needs full sunlight and a temperature of at least 68 to 77°F (20 to 25 °C) to grow its tubers. Hence, planting in open ground is meant for warm summer regions.
Elsewhere, container growing or greenhouse planting still works great. Anyhow, with seasons turning warmer as time passes, we might just get to grow sweet potato in places further and further north (or south, in the Southern hemisphere).
In mild climates, sweet potato tubers are planted in open ground in mid-spring or late spring. Temperature must hit that sweet spot of 68°F (20 °C). Tubers germinate from Late winter to early spring.
It’s already possible to buy sweet potatoes seedlings in pots or mini-clumps from garden stores, and transplant them to the open ground from late spring.
For those with a green thumb craving more control over germination: get your hands on tubers or even tuber fragments with at least one eye:
After about two weeks, the seedlings should be around four inches tall. That’s when to transplant them to open ground or a greenhouse. Whether in open soil or in a greenhouse:
It’s rare to find pests on sweet potato, but the occasional caterpillar worms its way around at times.
Sweet potato is not sown but started from tubers, then moved on as soon as the soil is warm enough. Here is the order in which the season unfolds.
| Stage | Season | What it involves |
|---|---|---|
| Sprouting tubers under cover | Late winter to early spring | Tubers laid horizontally on moist soil mix, a third buried, at 20 °C minimum (25 °C ideal) |
| Planting tubers in open ground | Mid-spring to late spring | Only in mild climates, once the soil reaches 68°F (20 °C) |
| Transplanting bought seedlings | Late spring | Pots or mini-clumps from garden stores go straight into open ground or the greenhouse |
| Flowering | Midsummer to early autumn | Flowers that remind us of other ipomoea species, over densely packed leaves |
| Harvest | Early autumn to mid-autumn, or late autumn if frost-free | Lift with a garden fork when the leaves turn soft yellow, then cure a day in the sun |
| Eating and storing | A fortnight after lifting | Starch turns to sugars; keep cool, dry and frost-free, ideally in a veggie silo |
Miss the warmth at the start of that sequence and the tubers simply never form.
Harvest season kicks off in early autumn or mid-autumn. Leaves turning a soft yellow hue is your cue. If it doesn’t freeze yet, keep them in the ground until late autumn.
Got a garden fork? Use it to uproot those tubers (a spading fork is great, too). Let them bask in the sun for a day for them to cure, but not for too long, and bring them in if it rains so they don’t get wet.
Wait a fortnight before munching, turning starch into sugars takes time. Store them in a cool, dry place away from frost. They’ve got a pretty long shelf life which you can greatly extend by keeping them in a veggie silo, not as long as regular potato, but they’re worth every bite!
Cooking a sweet potato? It’s pretty much like prepping regular spuds. Thanks to its hint of sweetness, it is also delicious in desserts too. Sweet potato isn’t just about taste; it’s full of potassium, vitamin A, and antioxidants.
The leaves and young shoots are edible too, cooked like spinach, unlike potato foliage which is toxic.
Never keep raw tubers in the fridge, as chilling gives them a hard core and a flat, stale taste once cooked.
The skin is thin enough to eat, so a good scrub often replaces peeling.
