Sweet potato slip - Time between start and putting them in the ground

Hello permies!  I'm going to grow sweet potato slips this year.  Yay!    

I'm going to do the "toothpick and tater in a jar method" or the "tater on its side in a pan of water method".  How much time should I plan on from when I put them in the water until I plant the rooted slips in the ground?  I've heard a month to let the slips form on the potatoes and then a few weeks to let the roots develop on the slips in a jar of water.  So I'm guessing 7 weeks but I haven't seen is explicitly stated anywhere.

Also, if you put them in a jar, which end goes down?  I'd assume the side that was closest to the mother plant goes up but I saw one youtube video where they said to do it the opposite way.

Thanks!

I was just getting ready to post that I'd started my slips too early (mid february) and have to figure out some way to pot them until planting time...here it is still a few weeks off.  I don't want them sitting in water to root for that long.

I've always laid  them lengthwise in water (halfway up the sw. potato) in my odds and ends of old crockery with good success.  For some reason this year I also did some in wide mouth quarts with toothpicks and they are sprouting about the same as the others but only from one end, of course.

I've never worried about which end was up...usually my potatoes from last years crop start sprouting from one end or the other and that's when I get them out to start slips.

This year was early though, I think because our house is warmer and the sweet potatoes in storage began to sprout too soon.

I think six weeks is about right.  I am pretty sure that rooting the slips doesn't take more than a week or so...much quicker than growing out the sprout itself.

Do you know what variety you have?  Mine are a cut leaf kind that was given to me more than 15 years ago.  I keep thinking they will play out and not produce as good but so far they have made wonderful large roots...and delicious

EDIT to add....there might be something helpful in my sweet potato thread here

good luck!

Thanks Judith!  I am a bit too early then.  My average frost free date is May 21 so it looks like I should start getting the roots wet about Apr 1.  If it takes them a bit longer it's fine since we don't get really warm here in early June anyways.

I don't know the variety but if I had to guess I'd say Beauregard.  

this year I started mine in a regular seed tray half filled with soil.  the Potatoes are all resting on their side and the soil is now a mat of roots.  I then took the slips and placed them in 6 pack cells.  I hope to keep them happy for the next month, because I started these things super early.

Did you keep the soil in the tray really wet?  Or just "normal"?  I saw a youtube video by imstillworkin where she put the roots on their sides in a pan and once the slips were ready she pulled them off and used the same tray of water to set them in to root.  So she'd just pick more slips off every few days and get them going in the corner of the same pan.  

I just picked them off as they grew.
They had 300w MH light and bottom heat, with regular watering.

Thanks!  Nice photo

Lots of good advice here - wish I would've checked before starting from a different blog post. Never did this before - 2 more months before they will be planted into black grow bags in Zone 4.
* Started halves of store-bought potatoes with the tooth-pick in water situation
* Took a while, but now I've got lots of little sprouts/slips from eyes ABOVE the water
* Last week I noticed that all the "halves" have roots from their bottom edge in the water - no "slips" attached - NO roots coming out from the slips above the water
This is completely not what I was expecting from the blog tutorial, nor what I've read in this discussion!
My thoughts: Can I do some surgery to excise a little of the flesh around the slip base and then hang that unit in water to grow roots? FYI, I'm using distilled water.
It might be possible to cut slices from the slips all the way down to and include the roots, but am feeling this wouldn't be successful.
I've read that placing a whole tuber in the ground lessens the production - can I do that in a pot and then cut them apart for final planting?
This is my first adventure of gardening in the Northland - so much to learn - know that sweet potatoes will be a challenge, but we love them.
THANKS so much for advice and wishing best to all.

Sweet potatoes are so forgiving you can start them months ahead and just keep the slips in potting soil. They don't need to have roots of their own; as soon as they're planted they grow roots. If you start them early you can just grow them longer and cut them in two to double your slips! You just need two leaf-lengths (I don't know the proper terminology for this stuff) under the ground to get good rooting.

This year I tried two methods to keep slips for a longer period: I had two potatoes started in water; the one I just stuck in the ground, and the other I broke the slips off and put them in the ground. Both ways worked just fine.

Seriously, as long as you have warmth and water you can hardly go wrong. I remember when I was a kid we just left the sweet potato in the water and had vines growing over our kitchen cabinets!