How to Start Sweet Potato Slips at Home: Step-by-Step Guide for Beginners

Starting your own sweet potato slips at home is easier than most gardeners realize—and you get stronger, healthier plants than anything you can buy. I’ve been starting slips for years for my Sonoma garden, and it’s become one of my favorite early-season rituals. Once you understand how sweet potatoes sprout, you’ll be able to produce dozens of vigorous slips from just one or two roots.

Here’s my simple, experience-based step-by-step guide for beginners.

Table of Contents

Choose the Right Sweet Potatoes

Not every sweet potato will sprout well—your starting root matters.

What works best:

Organic sweet potatoes (non-organic roots are often treated to prevent sprouting)
Firm, unblemished roots
Medium-sized tubers (they sprout more evenly than very large ones)

My experience:
I get the most reliable slips from varieties I’ve grown and stored myself—but store-bought organic roots also work very well.

Decide Your Method: Water Jar or Soil Tray

I’ve used both methods over the years. Each works, but the soil tray method produces stronger, earlier slips.

1. The Water-Jar Method

Cut the sweet potato in half.
Suspend the top half in a jar of water using toothpicks.
Keep the bottom half submerged and the top dry.

2. The Soil-Tray Method (my preferred method)

Place whole sweet potatoes on their side in a shallow tray.
Cover with 2 inches of moist potting mix.
Keep warm and lightly moist.

Why I prefer soil:
Slips grow sturdier stems and stronger initial roots, and the potato doesn’t rot as easily.

Provide Warmth—Sprouting Needs Consistent Heat

Sweet potatoes only sprout well when warm.

Ideal temperature: 75–85°F
Location tips:

On top of the refrigerator
Near a sunny window
On a heat mat (my go-to method)

My experience:
A heat mat cuts sprouting time nearly in half and gives me remarkably uniform slip growth.

Wait for Sprouts to Grow 4–6 Inches

In warm conditions, sprouts appear in 2–4 weeks. Let them grow until they have:

4–6 inches of length
Several healthy leaves
A sturdy central stem

Slips that are too small tend to stall during planting.

Remove Slips Without Damaging the Mother Root

Gently twist each slip at the base where it meets the potato. It should release easily.

My tip:
If a slip resists twisting, use a clean knife to carefully slice it free. This encourages the potato to produce more sprouts.

Root the Slips in Water

Place slips in a jar with the lower stems submerged.

Within 3–7 days, you’ll see white roots forming at the base.

My experience:
I wait until roots are 1–2 inches long before planting—this gives slips a head start and excellent transplant success.

Harden Off Before Planting

If you’ve grown slips indoors, introduce them to outdoor conditions gradually.

Day 1–2: Bright shade
Day 3–4: Morning sun
Day 5–7: Full sun

Slips adjust quickly, but hardening off prevents shock.

Plant Slips Deep for Strong Rooting

When planting outdoors, bury the slip so that 2–3 inches of the stem sits below the soil. Sweet potatoes root all along the buried portion, which leads to bigger yields.

My Sonoma tip:
I always plant in warm, loose soil—if the bed is cool or compacted, slips hesitate.

Final Thought

Starting sweet potato slips at home is simple, inexpensive, and incredibly rewarding. With warm temperatures, a good starter root, and steady rooting time, you’ll have vigorous slips ready to take off the moment they hit warm garden soil. This straightforward method has given me years of healthy plants and big harvests—and it works beautifully for beginners, too.