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This is positively farming media.
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Many home gardeners and market growers alike rely on seed
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companies and other suppliers for not just our seeds, but also
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our started plants, our roots or our bulbs.
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So things like garlic, onions, seed potatoes, these are often
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purchased rather than saved from our previous year's harvest or
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started at home. And sweet potatoes also fall
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into this category. For years I purchased started
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Sweet Potato slips to grow, and I often still do, just because
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of the quantity that I need. Today on Just Grow Something,
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we're going to go over three ways that we can easily get our
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own slips started, either from our own harvested sweet potatoes
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or from store bought ones. It's easier than you think, and
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even if you need a lot of slips, it takes up less room than you
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might think. Let's dig in.
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Hey, I'm Karen and I started gardening 18 years ago in a
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small corner of my suburban backyard when we moved to A5
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acre Homestead. I expanded that garden to half
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an acre and I found such joy and purpose in feeding my family and
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friends. This newfound love for digging
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in the dirt and providing for others prompted my husband and I
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to grow our small homestead into a 40 acre market farm.
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When I went back to school to get my degree in horticulture, I
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discovered there is so much power in food and I want to
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share everything I've learned with as many people as possible.
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On this podcast, we explore. Crop information, Soil health,
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pests and diseases, plant. Nutrition, our own nutrition,
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and so much more in the world of food and gardening.
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So grab your garden journal and a cup of coffee and get ready to
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just grow. Something a little note about
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the recording of this episode. I'm actually recording from
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inside Lulu, our tiny camper, because we are in Florida
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celebrating my father in So just keep that in mind as you
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listen to this episode. If you have not grown sweet
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potatoes before, you may not know that growing them is
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different from growing a regular Irish potato.
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Irish potatoes are grown from a piece of a potato with sprouting
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points that we call eyes, and that's just placed in the ground
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and then covered with soil. So the eyes sprout the shoots
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that grow above the ground, and that sends energy back down into
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the tuber below ground, which then sends out the roots with
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the new tubers on them, and that becomes the new potatoes that we
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harvest. Sweet potatoes, on the other
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hand, are grown from what we call slips.
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Essentially, these are shoots that have sprouted from a mature
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sweet potato that are then removed and allowed to root and
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then planted in a mound of soil. It's about 8 inches high or so.
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It can take a few weeks for your slips to get established once
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you plant them, but then after that the shoots will take off.
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They'll continue to grow and sprawl and then in the same
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manner as the Irish potatoes, they will send energy down into
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the roots which then produce the new tubers.
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Sweet potatoes are in the Morning Glory family, so you'll
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see these shoots very quickly turn into vines and those vines
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will take off and ultimately cover the exposed garden soil.
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And then they're they're just going to choke out anything else
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that attempts to grow there. They also put out those
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distinctive funnel shaped flowers indicative of most of
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the plants in the Convolvo ACA family.
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Here's the thing about sweet potatoes in an in ground
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situation. Because it's a vine, wherever
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the leaf nodes touch the ground, the plant sends out new roots
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and those roots can eventually yield more sweet potatoes.
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So if you have a really long growing season and a nice big
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garden bed that you can dedicate to sweet potatoes, you can get a
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ton of sweet potatoes from just a few slips.
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In fact, gardeners in warmer areas may need to spend some
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time redirecting those sweet potato vines out of the garden
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pads and back into the garden bed where they belong, because
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they can grow very aggressively and you can also grow them in
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pots and they just are beautiful.
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Those lovely vines just spill up and over the edge of the
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container, and so they put on a really pretty show and then you
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get an edible treat at the end of the growing period.
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I did a full episode on growing sweet potatoes back in episode
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94. I will link to that in the show
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notes, as well as the episode on growing those regular potatoes,
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which is episode 135 S How do we get these sweet potato slips to
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begin with? There are three main ways that
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you can start slips from sweet potatoes that you have on hand,
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whether they were from last season's harvest or from a
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neighbor or the farmers market or even from the grocery store.
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There's the water method, a container soil method, and the
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in ground method. There are pros and cons to each,
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and which one that you choose will depend on how much space
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you have, how long you're growing season is, and whether
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or not you have things like lights or heat mats indoors.
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To help facilitate some of this, let's start with the simplest
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method, the water method. All you need to start sweet
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potato slips in water is a Mason jar, toothpicks, water, and your
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sweet potato. You need to determine the
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rooting end of your sweet potato.
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Now, generally speaking, the rooting end is the skinnier or
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more slender end of the sweet potato.
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And if you wash it well and look really closely, you may already
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see tiny little roots emerging from a sweet potato that's been
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stored at room temperature. The opposite end is the
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sprouting end, the side that will produce our slips for us.
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Put your sweet potato about halfway into your Mason jar with
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the rooting end down, and then push toothpicks into the sides
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of the potato so they extend out over the lip of the jar to
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suspend the potato in place. Then add fresh water to the jar
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so that the bottom half of the sweet potato is submerged and
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the sprouting end is above the jar.
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You can now put the jar either in a sunny window where it gets
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some warmth and some light, or another warm spot like the top
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of the refrigerator, or on a seedling heat mat if you have
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one. If it's not in a window, you'll
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need to supply some artificial light, but it doesn't need to be
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fancy, just enough light to encourage growth.
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Once the shoots start to sprout, refresh the water when needed to
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keep the water level up, replacing it completely once a
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week to be sure the water doesn't get funky and cause the
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bottom of the potato to rot before forming roots.
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After a few weeks, you'll start to see the potatoes start to
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pull roots at the bottom, and then the sprouts will start to
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form at the top. These sprouts are your slips.
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Let them get about 6 inches tall and then we'll talk about what
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to do with them here in a minute.
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This water method is pretty simple and straightforward, but
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if you need a lot of slips, it may take up more room than what
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you have. You might not want a bunch of
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Mason jars with sweet potatoes sticking out of them, sitting
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all over your house for weeks on end.
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This is also the slowest method for sprouting them, generally
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taking at least a minimum of six weeks, sometimes as long as ten
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weeks depending on how warm you keep your jars.
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So the next method we can use is the container soil method.
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This is an indoor method. It's much faster and you can get
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a lot of slips from a pretty small space.
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But you're going to need some artificial lighting for this,
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and ideally A seedling heat mat, plus a place that you don't mind
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having a tub full of soil and potatoes sitting for about 6 to
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8 weeks. For this method, you'll need a
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shallow container, potting soil or seed starting mix, a seedling
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heat mat, and some artificial lighting for sprouting just a
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few sweet potatoes. The container you use can be
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something like a foil baking pan or a deep seedling tray if you
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want to sprout a larger amount of sweet potatoes.
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I've found. Those black plastic tubs that
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you can find at the hardware store that are used for like
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mixing concrete are perfect for this.
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They're shallow enough for the amount of potting soil that we
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want to use and easy to drill drainage holes into.
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Really any shallow container that can have some drainage
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holes but that also can have something placed beneath it to
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catch water will work. The size is really up to you and
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how many sweet potatoes you want to sprout and how much room you
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have to do it. All you're going to do is create
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drainage holes in the bottom of your container and put a layer
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of potting soil or seed starting mix in the container a few
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inches deep. Nestle your sweet potatoes into
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the soil, laying them flat, and then fill in with more soil
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around the potatoes until they're covered at least halfway
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up. The reason we do it this way
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instead of completely burying them is to prevent the potatoes
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from rotting before they get a chance to root and sprout.
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Put your container on top of something to catch the water, so
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like the lid to the baking sheet if that's what you're using, or
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another large container if you're using something else, and
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then water the soil thoroughly. We don't want it stopping wet,
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but you'll want to keep the soil moist as the roots begin to
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form. Put the container on top of the
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heat mat if you have one, which I highly recommend because it's
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definitely going to make this process go faster.
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The sooner you can get the sweet potato to form roots, the lower
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the chances that you'll have any of the tubers begin to rot with
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heat. It should take about a week for
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the roots to start forming, and then about another week or so
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after that to start seeing sprouts much faster than the
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water method. At this point, be sure to give
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the sprouts some light, similar to like growing seedlings
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indoors. Let them get to be about 6
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inches tall and then we'll talk about how to remove the slip for
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planting. Our final method for sprouting
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sweet potato slips is similar to the container soil method, and
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that's the in ground method. We'll be doing this out in our
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garden area, so the effectiveness of this method is
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going to depend on how warm your soil can get in the spring.
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For sprouting sweet potatoes outdoors, we want the soil
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temperature to be at least 65 Fahrenheit, or 18 Celsius.
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If your soil isn't warm enough on its own or waiting for it to
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warm up naturally won't give you enough time to get the slips
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sprouted before it's actually time to plant.
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You can use mini greenhouses, milk jugs, hoops with greenhouse
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plastic or black plastic mulch, or even tarps to warm the soil
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more quickly. You'll need to maintain the soil
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temperature to successfully sprout and grow your slips, so
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be sure it's something that can be maintained while also
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allowing for sunlight on the sprouts.
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Make sure your soil is loosened and well watered prior to
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planting your tubers. You can either bury just the
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rooting end of the sweet potato in the soil and leave the top
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sprouting half outside the soil, similarly to how we did it with
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the water method, or you can lay them flat like we did with the
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indoor method and cover them lightly with soil.
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Once again, we're going to keep the soil moist while we wait for
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the roots to form and the sprouts to pop up.
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So the warmer the soil is to start with and the warmer we
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keep it, the less likely we are to have any of the potatoes rot
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before they sprout. And just like with the indoor
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container method, how long it takes for the roots to start
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forming will be based on the level of moisture and warmth.
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This could be as quickly as a week, or it could take a couple
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of weeks if your soil is cool or if you allow it to dry out too
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frequently after the roots start to form, it should only be
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another week or two before you start to see these shoots
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popping up. Now, because these are outside
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and you'll have natural sunlight on them, the shoots will likely
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grow quickly to get to that 6 inch height that we want for our
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slips. Whichever method you choose may
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also be partially determined by how long you have before it's
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the ideal time to plant your slips.
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You want to wait at least a month after your last frost in
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the spring when the soil temperature is at least 65
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Fahrenheit or 18 Celsius, and when the nighttime air
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temperatures are consistently above 60 Fahrenheit, or 15.5
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Celsius. I actually wait until the soil
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temperatures are even warmer than that, around 70 Fahrenheit
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or 21 Celsius, which for me is usually around the first week in
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June. The slips just tend to root in
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and take off more quickly than if I plant them earlier, and our
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temperatures can fluctuate pretty wildly prior to that, So
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that's just what works best for me, which means I need to time
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the starting of my slips accordingly.
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I actually do a combination of the indoor container method and
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the in ground method. My soil temperatures outside
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aren't quite warm enough in the six to eight weeks before my
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intended planting date to sprout them in ground very quickly, and
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my seedling room is so full of plants at that point that I
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can't possibly squeeze in large containers of sweet potatoes
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too. So I use those black tubs that I
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mentioned in the same manner as the indoor container method, but
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I put them in my greenhouse so I'm sure to put them out there a
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few days before I put the tubers in so that the soil is nice and
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warm. I can water them as needed when
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I'm working in the greenhouse and then when they sprout they
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automatically get the light coming into the greenhouse for
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their growth. This has been the most effective
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way to sprout slips that I have come up with.
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If you don't have a greenhouse but you have some bed space in
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your garden, you can use the little pop up greenhouse covers
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that I've mentioned to warm the soil and allow you to use the in
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ground method. But if the bed that you plan to
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use for your sweet potatoes is taken up by something else, say
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early greens in the six or eight weeks before you plan to plant,
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then use a container. Put it outside and pop one of
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those little greenhouses over top of the container.
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You can technically even just use a bucket, Insulate around
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the bucket if your air temperatures are still cool, and
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then like pop a plastic milk jug or some other container on top
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to keep them warm. Get creative if you need to
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experiment and find out what works for you.
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Try all three methods at the same time, even and decide from
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there. No matter which method you
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choose, once your sprouts get around 6 inches tall, it's time
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to remove them from the sweet potato and use them as slips.
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To remove the slips from the potato, carefully twist or cut
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them from the tuber. If little roots have formed
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where the sprout meets the tuber, try to keep those intact.
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Remove the lower leaves from the sprouts and at this point you
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have two options. The 1st is to put the bottoms of
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the slips in a jar of water for a few days to pull visible roots
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before planting. If you're new to growing sweet
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potatoes or you have soil that isn't very loose or loamy, this
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method ensures your new slips take root more quickly because
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of the actively growing roots. But if you were an experienced
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sweet potato grower and your soil is conducive to this, you
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can just plant those newly harvested slips right into the
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prepared bed. Bury the slips all the way up to
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the top leaves and keep them evenly moist to promote those
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roots to grow in the soil. No matter which way you choose,
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your slips should be planted about 12 inches apart from each
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other and the stem should be about four inches down into your
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8 inch deep mount. If you really want to promote
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fast root growth in your newly transplanted slips, water them
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in with a solution that contains A phosphorus amendment to
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encourage that fast root development.
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So how many sweet potatoes do you need to be sprouting for the
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number of slips that you want to plant?
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You can usually count on a minimum of 10 slips per sweet
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potato initially, and if you leave the tuber in the soil or
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the water longer, you can often get many more than these,
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sometimes up to 30 slips per potato.
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It just depends on how much time you have.
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I generally count on getting 10 to 15 per tuber harvested all at
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the same time, so I start my tubers accordingly.
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I can fit around 20 sweet potatoes in each of my black
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bins, and I have six of those bins, so I can get anywhere from
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1200 to 1500 slips from my setup, and these just all fit
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under one bench in my greenhouse until they sprout and then I
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pull them out into the sunlight. So it's not a major process to
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start your own sweet potato slips, and it can be done in a
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very little space. This is especially helpful if
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you've found a specialty variety that you really like, but
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they're hard to find or sometimes in short supply, like
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some of the purple or the white varieties.
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Or if you've had a really stellar year for growing your
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sweet potatoes and you want to preserve those genetics for the
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next season. The key is curing and storing
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some of that harvest properly in the fall so that they're still
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intact and able to be used to sprout those slips come
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springtime, Or saving some from your favorite farmers market
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vendor and growing some of your own next season.
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And if all else fails, grab an organic sweet potato from the
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grocery store and give it a shot.
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And here's one last trick I learned from my colleague Zach
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Hoppenstadt when he was doing his sweet potato trials with
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Kansas State University. When sprouting slips from tubers
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harvested in the previous year, raise the temperature in your
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storage area to between 70 and 85 degrees Fahrenheit, or 21 to
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29 degrees Celsius to induce pre sprouting.
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This is going to help rooting and sprouting move much more
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quickly. Until next time, my gardening
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friends, keep on cultivating that dream garden and we'll talk
00:18:18
again soon. You.
00:18:19
Just finished another episode of the Just Grow Something podcast.
00:18:23
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00:18:25
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00:18:29
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00:18:32
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00:18:35
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00:18:40
friends keep learning and keep growing.