White Yam

Family: Convolvulaceae Root Vegetable

Silken-smooth flesh emerges in a luminous white that feels almost pearlescent in the garden—sweet, mellow, and quietly aromatic when grown to maturity.

White Yam forms an even, tapered root with a creamy interior and a tender, velvety texture that shines in roasted wedges, mashed bowls, and comforting purees, with its naturally balanced sweetness also lending itself beautifully to soups and gratins. For home gardeners, it’s a standout harvest: clean-looking, richly flavored, and made for turning everyday meals into something special.

Light: Full SunMaturity: 90 DaysHabit: Vine

Planting schedules and alerts are optimized for Columbus (Zone 6b).

Crop Dates

Milestone	Date
Start Indoors	Direct Sow
Last Frost	Apr 25th
Transplant / Sow Outdoors	Apr 25th
Harvest Begins	Jul 24th
Harvest Ends	Oct 16th

Crop Details

Trait	Value
Days to Maturity	90
Sun Requirements	Full Sun
Growth Habit	Vine
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	75
Min Soil Temp (°F)	65
Min Night Temp (°F)	55
Harden Off (days)	Not Required

Culinary Notes

Chef's Note

This white-market sweet potato is all about creamy, almost custardy texture with a restrained sweetness—so it rewards heat that caramelizes the outside while keeping the center plush. It stands up to rich fats like butter or coconut but stays clean when you cut it with citrus or spice.

Best Uses

roasted wedges (high-heat for caramelized edges; tender center)
silky mash or purée with butter and salt
thick, comforting soups for body without heaviness
baked gratin layers with cream or coconut milk

Flavor Profile

mild, mellow sweetness subtle vanilla-leaning aroma creamy, velvety interior soft, spoonable texture when cooked through

Kitchen Pairings

brown butter cinnamon lime or lemon juice smoked paprika ginger coconut milk

Frequently Asked Questions

What pest or disease commonly affects Ipomoea batatas (white yam) and how can I manage it?

Sweet potato–type crops like Ipomoea batatas commonly suffer from sweet potato weevil and fungal rots (especially in warm, wet soil). Inspect foliage for wilting and check tuber surfaces at harvest for dark, tunneled damage; control starts by planting only healthy slips and rotating beds. During the growing period, avoid overhead watering and keep soil evenly moist but not waterlogged to reduce rot, and remove any diseased plants promptly.

How often should I water Ipomoea batatas during the main growing phase?

During active vine growth (about mid-summer through bulking), water deeply about once every 5–7 days, but only when the top 1–2 in (2–5 cm) of soil has dried. Aim for steady moisture to encourage tuber swelling while preventing waterlogged conditions that trigger rot. If your soil stays damp or drains poorly, reduce frequency and improve drainage rather than increasing watering.

How do I tell when white yam (Ipomoea batatas) is ready to harvest?

Harvest at roughly 90 days after planting slips, or when vines begin to yellow and die back. Gently dig a test tuber—when the skin is set and resists rubbing, the crop is ready. For best keeping quality, cure freshly harvested tubers in warm, humid conditions for 4–7 days before storing.