Sweet potato

Sun

Full sun; light shade is tolerated but usually reduces the root crop.

Water

Water regularly while plants establish and roots develop, allowing the surface to dry slightly between waterings. Avoid waterlogged soil.

Soil

Loose, well-drained sandy loam, ideally pH 5.5-6.5. Heavy, compacted or freshly manured soil can produce misshapen roots.

Height

6-12 in (0.15-0.3 m)

Spread

3-10 ft (0.9-3 m)

Flowers

Occasional pale pink to lavender funnel-shaped flowers with darker throats in summer; many food varieties rarely flower.

Foliage

Trailing stems carry green, heart-shaped to deeply lobed leaves. Ornamental selections may have purple, bronze or lime-green foliage.

Growth

Fast in warm weather; slow in cool soil.

Care needed

Medium

• Heat tolerant
• Low allergen
• Edible

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   0.5 ft (0.15 m)

2. After 1 year

   0.7 ft (0.22 m)

   full size

Full size in one season.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

In the garden

Spreads vigorously: plan to contain it.

Growth rate

Moderate

• Plant rooted shoots, called slips, after frost danger has passed and soil has warmed to at least 18°C (65°F).
• Space slips 12-18 in (0.3-0.45 m) apart, leaving room for trailing growth.
• Keep soil evenly moist during establishment and root swelling, but never saturated.
• Use modest amounts of balanced fertilizer; excess nitrogen encourages leaves rather than storage roots.
• Weed before the vines cover the soil, and mulch once the ground is warm.
• Use a large container with drainage holes if your garden soil stays wet or compacted.

Pruning. During summer, redirect wandering vines rather than repeatedly cutting them back. Trim only damaged growth or stems blocking paths, since heavy pruning can reduce the crop.

Lift storage roots when the variety's expected growing period has elapsed, usually 90-150 frost-free days, and a test plant has roots of useful size; harvest before frost damages the vines. Dig carefully to avoid breaking the skin, then cure sound roots for about 7-14 days in warm, humid, ventilated conditions around 27-30°C (81-86°F) before storing somewhere cool but frost-free.

Late winter

Order slips or start healthy, untreated storage roots indoors in warmth to produce shoots.

Spring

Prepare a sunny, well-drained bed and warm the soil under a cover in cool climates.

Late spring

Harden off slips gradually and plant only once nights and soil are reliably warm.

Summer

Water during dry spells, weed early and guide vines away from paths and smaller crops.

Early autumn

Check a test plant for root size and lift the crop before frost or prolonged cold, wet weather.

Autumn

Cure undamaged roots, then store them dry and ventilated at about 13-16°C (55-61°F).

• Let vines cover sunny vegetable beds as a productive seasonal groundcover.
• Trail foliage over the edges of large containers or raised beds.
• Use beside upright peppers or okra, allowing enough room to avoid smothering them.
• Combine bold leaves with upright grasses in warm-climate edible borders.

Garden styles it suits: Potager (kitchen garden), Edible landscape, Homestead, Tropical, Modern courtyard and Family-friendly.

Plant it with: Okra, Peppers, Basil and French marigolds.

Wildlife: Flowers, when present, attract bees. Dense foliage shelters small invertebrates, while deer and rabbits may browse the leaves.

• Poor root development: provide a longer warm season, full sun and modest nitrogen; choose an early-maturing food variety.
• Sweet potato weevils in warm regions: use clean planting material, rotate crops, remove infested roots and earth up exposed roots to reduce access.
• Wireworms and other soil grubs: inspect the site before planting, avoid recently converted grassland and rotate to a different bed.
• Root rot and storage decay: improve drainage, avoid harvest wounds, cure sound roots and discard soft or mouldy ones.

Healthy sweet potato roots and foliage are not known to be toxic to people, cats, dogs or horses. People commonly eat the roots and cooked leaves; unlike ordinary potato foliage, sweet potato leaves are edible. Mould-damaged roots can contain dangerous toxins, particularly for livestock, and should not be fed to animals. Do not eat ornamental plants treated with pesticides unsuitable for food crops.

Where it spreads. Vines can spread aggressively and root at stem nodes in frost-free tropical gardens, including northern Australia and Hawaii. Keep growth out of neighbouring vegetation and do not dump living stems in natural areas.

• Potato (Solanum tuberosum)

  Potato grows upright and has compound leaves made of separate leaflets; sweet potato trails and has single, sometimes lobed leaves. Potato foliage is poisonous.

• Chinese yam (Dioscorea polystachya)

  Chinese yam twines upward and often produces small aerial bulbils where leaves meet stems; sweet potato usually trails and roots along its stems.

• Beach morning glory (Ipomoea pes-caprae)

  Beach morning glory has thick, rounded leaves with a deep notch at the tip, resembling a goat's hoof, and commonly grows on coastal sand.

The species name batatas comes from batata, a Taíno name for sweet potato.

Propagation. Grow from rooted shoots called slips, taken from healthy storage roots, or root stem cuttings in warmth. Use certified disease-free planting material where available; supermarket roots may carry disease or have been treated to delay sprouting.

Accepted botanical name

Ipomoea batatas

In the US and Canada

Introduced in Hawaii, the lower 48 states, Navassa Island, Pacific Basin, Puerto Rico, Puerto Rico, US Virgin Islands and US Virgin Islands.

Native range

Belize, Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico Gulf, Mexico Northeast, Mexico Southeast, Mexico Southwest and Nicaragua.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.