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A Fast and Easy Way to Make Sweet Potato Slips

Sweet potatoes aren’t grown from seed – they are grown from slips. A slip is a rooted sprout from a mature sweet potato. You can order sweet potato slips online, or you can grow your own. If you’re wondering how to grow sweet potato slips, you’ve come to the right place.

Begin the process about 8-12 weeks before your planting date for sweet potatoes. Here in the low desert of Arizona, our planting window for sweet potatoes is from March – June.


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How to grow sweet potato slips: Choose which method you would like to use

There are a few methods for growing sweet potato slips. I’m sharing three successful methods I’ve used.


1. The Traditional Water Method

The traditional method of making sweet potato slips is suspending the sweet potato in water. This method works, but often takes 6-8 weeks (or more) to produce slips.

Choose this method if you have plenty of time before you plant and don’t have indoor lighting. A bright window works well for this method.

How to make sweet potato slips

Pros: Simple

Cons: Takes longer; requires frequent changing of water.

Jump to instructions for the traditional water method


2. The Indoor Soil Method

In my experience, the indoor soil method of making sweet potato slips is a much faster way to make sweet potato slips. This method usually takes around 4-6 weeks. 

Choose this method if you would like slips faster, and you have bright indoor lighting available.

Pros: Quickest method

Cons: Requires indoor lighting & heat mat for best results. Must keep the soil moist. Chance for potato rotting.

Jump to the instructions for the indoor soil method


3. The Outdoor Soil Method

The outdoor soil method of making sweet potato slips works best in warm climates. This method takes 4-6 weeks once the soil is warm enough.

Choose this method if you have a long growing season and don’t want to bother with starting slips indoors.

Sprouts forming using the outdoor soil method of starting sweet potato slips

Pros: Easiest method; does not require any upkeep if your garden is already being watered.

Cons: Soil must be warm before you begin. Areas with short-growing seasons may not have enough time to produce slips.

Jump to the instructions for the outdoor soil method


Before you begin:

The first step for all three methods is to choose a healthy organic sweet potato. Organic potatoes are less likely to be treated with a sprout inhibitor. 

Do you have a sweet potato beginning to sprout in the cupboard? Perfect! Now you have a head start in whichever method for sprouting sweet potato slips you choose.



1. Traditional “water method” of making sweet potato slips

Suspend half the sweet potato in a jar of water using toothpicks.

Does it matter which half of the potato is submerged in water when making sweet potato slips? Yes, the rooting end should go in the water. Here are a few ways to determine the difference between the rooting end and the sprouting end:

  • Look for small thin roots on one end. This is the rooting end.
  • One end may be larger with more eyes. This is the sprouting end.
  • The end of the sweet potato that tapers is typically the rooting end.

You want the bottom (rooting) half to be immersed in water and the top (sprouting) half above the jar. Roots will form in the water, and sprouts will form in the top part of the potato. 

Providing warmth (a seedling warming mat or on top of the refrigerator) and light (a grow light or sunny window) will speed up the process considerably

Keep the water level up in the jar and keep the water fresh by replacing it every week or so. Within a few weeks, roots will develop first, and then sprouts will start to form on the suspended potato. 

Once several 5-6 inch sprouts have formed, see the rest of the directions below.



2. Faster “indoor soil method” of making sweet potato slips

  • Poke holes in the bottom of a foil pan
  • Fill foil pan with potting soil or seed starting mix.
  • Moisten soil. 
  • Nestle sweet potatoes in soil, covering about half the potato with soil.
  • Place the lid under the pan to catch any excess water coming out of the holes.
  • Keep soil moist as roots and sprouts form.

Once again, providing warmth (a seedling warming mat or on top of the refrigerator) and light (a grow light or sunny window) will speed up the process considerably

If the sweet potato becomes soft or rotten, you may need to begin again.

In about a week, if you wiggle the sweet potato, you will feel that roots are forming in the soil. Within another week or two, small sprouts will begin to grow from the top of the sweet potato. Once several sprouts have grown to 5-6 inches long, remove the slip.

You may be able to remove the slip with roots attached. If so, you can go ahead and plant. If there are no roots, go ahead to the next step.


3. “Outdoor soil method” for making sweet potato slips

Bury the sweet potato halfway in warm soil.
Bury the sweet potato halfway in warm soil.
  • Check soil temperature. Once the soil is at least 65°F (18°C), you can begin.
  • Moisten soil. This is the soil thermometer I use.
  • Bury the bottom (rooting half) of sweet potatoes in the soil, covering about half the potato with soil.
  • Use a milk jug or cloche to warm the soil and encourage rooting and sprouting.
  • Keep soil moist as roots and sprouts form.

If at any time the potato becomes soft or rotten, you may need to begin again.

Sprouts forming using the outdoor soil method of starting sweet potato slips
Sprouts forming using the outdoor soil method of starting sweet potato slips

Within a week or two, if you wiggle the sweet potato, you will feel that roots are forming in the soil. Within another week, small sprouts should begin to grow from the top of the sweet potato.

Once several sprouts have grown to 5-6 inches long, remove the slips from the sweet potato and begin the next step.


Whichever method you choose for making sweet potato slips (the water method or either soil method), the next steps are the same:

  • When sprouts are about 5-6 inches tall, remove sprouts from the sweet potato by carefully twisting off or cutting off at soil level.
  • Remove lower leaves from sprouts and let “root” in a jar of water. Roots will develop quickly; you should begin to see roots in 1-2 days. 
  • Placing the jar on a seed germination mat for warmth and under a grow light will speed up the process of developing roots. 
  • Keep the water level high in the jar. Switch out the water about once a week to keep the water fresh. Discard wilted or rotten slips. 
  • Once roots are fully formed and several inches long, it’s time to plant
  • Plant the rooted sweet potato slips about 12-18 inches apart and 4 inches deep. 
  • Water newly-planted slips well and feed with a starter solution high in phosphorus to ensure the plants continue rooting.

One sweet potato will produce a dozen or more sprouts. Allow sweet potato to continue rooting and producing slips until you have as many as you (and your neighbors) need.


How to Grow Sweet Potatoes #sweetpotatoes #gardening #garden #arizonagarden #gardeninginarizona #desertgarden

Once you’ve grown sweet potato slips, learn how to grow sweet potatoes in this blog post. 


Perpetual Herb, Fruit & Vegetable Planting Calendar Zone 9b
  • PLANTING GUIDE: Each month lists vegetables, fruit & herbs to plant outside & seeds to start indoors.
  • HARVEST GUIDE: Photos show what may be ready to harvest that month.
  • Planting dates are for the low desert of Arizona (zone 9b).

If this post about how to make sweet potato slips was helpful, please share it:

 

garden

Thursday 30th of November 2023

A question, not a comment. Will the slips produced from the sweet potato provide the same sweet potatoes as the parent sweet potato used to get the slips from?

Angela Judd

Thursday 30th of November 2023

Yes.

Vicky

Monday 20th of November 2023

I stuck a few stringy sweet potatoes in my flowerbed last year and raised some huge potatoes! Why not just use the small potatoes instead of growing slips?

Angela Judd

Tuesday 21st of November 2023

Nice! Of course, that can work too. I've had the best success using slips, but there are many ways.

Floyd Lipe

Monday 11th of September 2023

Guess I did mine wrong. I had heard to plant half way so I put mine on their side and as they sprouted the8put on roots to where I could immediately plant when. I separated them from the potato. My first were from a local Gardner. I did read to use organic if you buy from the store

Angela Judd

Monday 18th of September 2023

I don't think there's a wrong way - lots of great options that all end up with the same result.

Dustin Finamore

Monday 14th of August 2023

Hi! Thanks for all the tips. I have slips that rooted and I planted them in soil a few weeks ago. The one leaf on the slips is still pretty and green however it’s not growing at all. Did I plant them too early or do I just need to wait longer? Thanks for your help

Angela Judd

Monday 14th of August 2023

If the leaf is still alive there are roots growing below the soil and you will see growth above ground soon.

Joanne

Sunday 25th of June 2023

I think I want to try the in ground method, since we live in Georgia in the mountains (Zone 7a) and the soil is warm enough to make the slips. What do you mean by using milk jugs or cloche to warm the soil? How far down do you place the whole sweet potato in the soil? thank you

Angela Judd

Monday 26th of June 2023

I place the sweet potato halfway in the soil. If your soil is not warm, using the milk jug on top of the soil over the sweet potato can help to warm the soil and speed things up.