How to Plant Sweet Potato Slips: The Art of Growing Your Own Sweet Harvest

I've been growing sweet potatoes for nearly two decades now, and I still remember the first time I held a sweet potato slip in my hands – this fragile, almost alien-looking sprout that would somehow transform into pounds of delicious tubers. It felt like magic then, and honestly, it still does.

Sweet potato slips are essentially rooted sprouts that grow from mature sweet potatoes. Unlike regular potatoes (which aren't even related, despite the name), sweet potatoes don't grow from seed potatoes or eyes. They need these slips, and learning to plant them properly is your gateway to homegrown sweet potato abundance.

The Sweet Potato Slip Journey Begins

Before you can plant slips, you need to understand what you're working with. A slip is basically a shoot that emerges from a sweet potato when you create the right conditions. Each slip develops its own root system while still attached to the mother potato. When you separate and plant these slips, they become individual sweet potato plants.

I learned this the hard way my first year. I stuck whole sweet potatoes in the ground like regular potatoes and waited. And waited. Nothing happened except some very confused earthworms and a lesson in humility.

Timing Your Planting Like a Southern Grandmother

Sweet potatoes are heat lovers – they're originally from Central and South America, after all. In most of the United States, you'll want to plant your slips after the soil temperature consistently stays above 60°F, ideally closer to 70°F. For me in North Carolina, that's usually mid-May, but I've learned to let the dogwoods tell me when. Once they're in full bloom and the nights stop dipping below 50°F, it's go time.

The old-timers around here say to plant sweet potatoes when the whippoorwills start calling at dusk. I used to think that was just folklore, but after tracking it for years, they're surprisingly accurate. Nature has its own calendar.

Preparing Your Plot: More Than Just Digging

Sweet potatoes need loose, well-draining soil. They're not particularly fussy about fertility – in fact, too much nitrogen will give you gorgeous vines and disappointing tubers. I've had my best harvests in soil that would make tomato growers weep.

What matters more is the physical structure of your soil. Sweet potatoes develop underground, and they need room to expand. Heavy clay soil will give you weird, twisted potatoes that look like modern art sculptures. Been there, harvested that.

I work my beds to about 8-10 inches deep, mixing in some compost if the soil is particularly heavy. Some folks build raised rows or mounds, which helps with drainage and makes harvest easier. After years of experimenting, I've settled on 10-inch high raised rows spaced 3 feet apart. It's not traditional, but it works beautifully in my garden.

The Actual Planting Process

When your slips arrive (or when you've grown your own), they might look a bit sad. Don't panic. Sweet potato slips are tougher than they appear. I've planted slips that looked completely dead and watched them spring back to life within days.

First, I soak the slips' roots in lukewarm water for about an hour before planting. This isn't strictly necessary, but I find it helps them establish faster, especially if they've been shipped or have dried out a bit.

Plant the slips deep – much deeper than you might think. I bury them up to the top leaves, leaving only the growing tip exposed. All those buried nodes along the stem will develop roots, creating a stronger plant. Space them 12-18 inches apart in the row. Closer spacing gives you more but smaller potatoes; wider spacing produces fewer but larger tubers.

Here's something most guides won't tell you: plant on a cloudy day or in the evening. Sweet potato slips can be shocked by intense sun right after planting. I learned this after losing half a bed to what I call "slip sunburn" one particularly brutal June afternoon.

The Water Dance

Water thoroughly after planting, but then ease off. Sweet potatoes are surprisingly drought-tolerant once established. In fact, overwatering, especially late in the season, can cause the potatoes to crack or develop poor flavor.

I water deeply once a week for the first month, then let nature take over unless we hit a serious dry spell. The plants will tell you if they're thirsty – the leaves will look dull and start to droop in the midday heat.

The Waiting Game and What Happens Underground

This is where patience becomes a virtue. Sweet potatoes take their sweet time – usually 90 to 120 days from planting to harvest, depending on the variety. During this time, the vines will spread like they're trying to take over the world. Let them. Those vines are solar panels, converting sunshine into the sugars that make sweet potatoes sweet.

Underground, something remarkable happens. The slips develop a network of roots, and some of these roots begin to swell into storage roots – your future sweet potatoes. It starts happening about 6-8 weeks after planting, but you won't see evidence above ground. The plant just keeps vining along, giving no hint of the treasure developing below.

Managing the Jungle

Sweet potato vines can get unruly. Some people religiously lift and move the vines to prevent them from rooting at nodes along the ground. The theory is that these additional roots steal energy from tuber development. I used to do this religiously until one year I got lazy and didn't. That year produced my biggest harvest ever. Now I leave them alone unless they're invading other crops.

What I do recommend is keeping the area weed-free for the first month. After that, the sweet potato vines usually shade out most competition. It's like they create their own mulch.

The Pest and Disease Reality

Here's where I might ruffle some feathers: sweet potatoes have fewer pest problems than almost any other crop I grow. Yes, there are sweet potato-specific pests like wireworms and sweet potato weevils, but in most home gardens, they're not significant issues.

The bigger problem is usually four-legged. Deer love sweet potato leaves, and voles can tunnel in and nibble the tubers. I've had entire plants disappear overnight thanks to deer. A good fence is worth its weight in sweet potatoes.

Knowing When to Harvest

Sweet potatoes don't really tell you when they're ready like tomatoes or peppers do. You have to go by time and weather. Most varieties need at least 90 days, but they can stay in the ground longer if the weather cooperates.

The critical factor is soil temperature. Once it drops below 55°F, you need to harvest quickly. Cold soil damages sweet potatoes in ways that might not show up immediately but will cause them to rot in storage. I start checking soil temperature in late September and plan accordingly.

Some folks wait for the first light frost to kill the vines, then harvest immediately. This works, but it's playing with fire. A hard frost can damage the potatoes if it penetrates the soil.

The Art of Digging

Harvesting sweet potatoes requires a gentle touch. They bruise easily when fresh, and those bruises lead to rot. I use a garden fork, starting about a foot away from the plant and working carefully inward. It's like archaeological excavation – slow and methodical beats fast and careless every time.

The first time you unearth a cluster of beautiful sweet potatoes that you grew from a tiny slip is genuinely magical. I still get excited every harvest, even after all these years.

The Critical Curing Process

Fresh-dug sweet potatoes aren't actually very sweet. They need to cure – a process where starches convert to sugars and the skin toughens for storage. Ideally, you want 80-85°F and 85% humidity for 7-10 days.

I cure mine in my garage with a space heater and damp towels. It's not perfect, but it works. Some people use a spare bathroom with a space heater and pans of water. The improvement in flavor after proper curing is dramatic – it's the difference between a starchy root and dessert.

Beyond the Basics

After years of growing sweet potatoes, I've developed some unconventional practices. I grow some in large containers – at least 20 gallons – which makes harvest a breeze. Just dump the container and pick out your potatoes. No digging, no damaged tubers.

I've also experimented with growing slips from grocery store sweet potatoes. Despite what you might read about them being treated to prevent sprouting, I've had good success with organic ones. It takes longer, but it works.

The Deeper Satisfaction

There's something profoundly satisfying about growing sweet potatoes. Maybe it's the transformation from slip to harvest, or the fact that you're growing a crop that can genuinely sustain you. A single plant can produce 3-5 pounds of nutritious food that stores for months.

Or maybe it's simpler than that. In a world of instant everything, sweet potatoes force you to slow down, to work with the seasons, to trust the process. You plant these unlikely looking slips in spring, tend them through summer, and harvest as autumn arrives. It's a rhythm as old as agriculture itself.

Every fall, as I dig my sweet potatoes and layer them carefully in boxes for curing, I'm already planning next year's crop. Which varieties to try, where to plant them, whether this might be the year I finally build that perfect curing chamber. The cycle continues, and I wouldn't have it any other way.

Growing sweet potatoes from slips isn't just about producing food. It's about connecting with the soil, understanding the seasons, and participating in the ancient dance between human and plant. Once you've tasted a sweet potato you grew yourself, cured to perfection and roasted until caramelized, you'll understand why some of us get a little obsessed with these remarkable plants.

Authoritative Sources:

Bonnie Plants. "How to Grow Sweet Potatoes." Bonnie Plants, www.bonnieplants.com/how-to-grow/growing-sweet-potatoes/.

North Carolina State Extension. "Sweet Potatoes." NC State Extension Publications, content.ces.ncsu.edu/sweet-potatoes.

Relf, Diane, and Alan McDaniel. "Sweet Potatoes." Virginia Cooperative Extension, www.pubs.ext.vt.edu/426/426-413/426-413.html.

Smith, Edward C. The Vegetable Gardener's Bible. Storey Publishing, 2009.

United States Department of Agriculture. "Sweet Potatoes." USDA National Agricultural Statistics Service, www.nass.usda.gov/Publications/Todays_Reports/reports/vegean21.pdf.