Taiji
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Starting sweet potatoes

I have a little more space this year, so I wanted to try some sweet potatoes. Today I went to the health store and bought 2 sweet potatoes; 2 different varieties. They're organic so I'm assuming they will sprout not being treated with some kind of sprout inhibitor. I was going to use the "suspend the potato in a jar of water with toothpicks method". I think I read to begin this method about 90 days before you want to set out the plants in the garden. Does that sound about right?

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applestar
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Re: Starting sweet potatoes

I prefer not to damage the potato with tooth picks. They can start to mold and rot from the scars.

I also had better success laying the tubers on their sides so full length of the one side of the tuber is moistened -- reason for this is sometimes it's difficult to determine which way is the tip end and which end was attached, and also, the tubers seem to grow shoots/slips in clusters and it's hard to tell where they are going to grow from.

If you suspend one half in the water you might end up with the critical end submerged.

They like to be 80-85° to start growing. I have trouble getting them started until it's warmer in spring -- starting earlier just means watching the tubers do nothing until we start getting those sunny sudden heat waves (Typically not until April here) -- but if you can get them growing by about a month before planting (soil needs to be warm, too so at least not until your garden is warm enough to plant beans and melons) you'll be fine. Once they start to grow, they are monsters and will quickly take over the (indoor) space. :roll:

I think about two weeks for the sprouts to grow enough to slip size, two more weeks to remove and grow the slips individually with own roots, then plant in garden after the soil is warm enough is approximately the right schedule. You don't want the slips to be too overgrown and still have to keep them inside. So specifically, 90 days seems too far ahead to me?

I also had success growing them by half burying them in sandy mix in a container and double bagging in black and clear plastic bags, then keeping them in sunniest part of the garden (this was obviously after the last frost).
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Taiji
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Location: Gardening in western U.P. of MI. 46+ N. lat. elev 1540. zone 3

Re: Starting sweet potatoes

Thanks for all the info! That was another question I had; does the tuber have a right side up or upside down to it? I like the idea of laying them on the side. I didn't realize they could be ready to plant so quickly. So, maybe these potatoes are destined for the dinner table instead!

Maybe when I do start them I can lay them on their sides in a shallow pan of water, or pan of really moist sand on a heat mat.

I think my plan was also to take the rooted slips and put them in their own pots for awhile too before placing outside, but maybe that is not a necessary step.

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Gary350
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Re: Starting sweet potatoes

I put sweet potatoes in a large mouth jar or can with water half way up the potato. Change the water every other day or the potato will rot. Buy potatoes that already have eyes with sprouts. It takes 3 or 4 weeks for the potato to grow vines. Wait until froze is over before you plant. Cut potatoes in pieces, plant the potato piece with vines coming up on the ground. No more than 3 vines per cut potato piece. My sweet potato vines always get about 25 to 30 feet long. You can pull the vines around the mother plant in a circle with the circle getting larger each time you go around this keeps vines from spreading all over the while garden. You can also plant your potatoes in the center of a 50 foot row and make the vines grow 25 feet in both directions in a 4 foot wide row. Put a shovel of dirt on the vines every 4 feet that will make the vines grow roots and more potatoes at each satellite spot. Give plants lots of water. Keep out the grass and weeds they steal water from the potato plants. I plant my sweet potatoes in April and let the frost kill them in November. The mother plant will make 2 times more potatoes than the satellite spots where the vine has sprouted roots. All the extra roots every 4 feet along the length of the vine makes all the potatoes grow much larger. Sweet potatoes love hot weather they do great here in TN and also did great when I lived in Phoenix. Last time I planted sweet potatoes I had 130 lbs of potatoes from 3 plants. I don't like sweet potatoes so I gave them all to the homeless shelter 2 weeks before Thanksgiving.

imafan26
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Re: Starting sweet potatoes

I prefer to put sweet potatoes in a tree container. Mainly because they are sprawling and it is easier to get all of the tubers out of the pot but not so easy to find all of them in the ground.

A popular sweet potato leaf that is grown here does not produce any tubers, it is grown for its' leaves.
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Taiji
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Location: Gardening in western U.P. of MI. 46+ N. lat. elev 1540. zone 3

Re: Starting sweet potatoes

Good info. Thanks all! So can all sweet potato leaves be eaten?

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