sweet potato vine, now what?

I sprouted a sweet potato which is vigorously doing its thing in a small container in the windowsill. It will be a good 4 months  (closer to 5) before it could possibly go outside. If I put it into a big pot would it consider making tubers? if so, how big a pot should it be, or can I  "graduate " it as it grows?Or should I just settle for a very attractive house vine?

It's a tough little sucker..it's run out of water at least twice, and the water it does get tends to be greywater from shampoos and such. Yet it  always comes back with new sprouts,and they aren't leggy  like most plants get with just a windowsill for light.  I'd like to see its determination rewarded, but I'm a northern person and have no experience with these plants, so any help appreciated. 

has it just started to sprout? is it a special variety you cant buy again? i got ahold of these extremely good japanese sweet potatoes, problem was someone gave them to me in october. they started to sprout in the bag i was given them in. so i put them in cold storage. basically its outside, dry, storage( old fridge ) but any cold dry place will do. i have had them in there since and dont plan on growing them until may.  they are perfectly fine and have shoots about 2 inches long.

sweet potatoes aren't grown in this neck of the woods..this was just a chunk off the end of one from the store to see what would happen.
It's now a very pretty vine about a foot long with two other shoots about 8 inches waving about and reaching for the window. all out of just the end about a half an inch thick.
I have it now in a small pot but wondering just what would be best to do with it..we can't put anything tender outside until June up here. It's trying so hard  (I was away a couple of times and both times it came back from being a pathetic little shrivelled lump) so  I'd like to help it do whatever is reasonable to expect it to do.

I have kept japanese sweet potatoes alive in containers for YEARS, but this is in subtropical FL where they are perennial.  They will make tubers in containers, but not be very productive, or at least in my experience. 

You can keep the sprouting vines in just water for months, given a little warmth and light. 

You can cut vines anytime, put them in water for a week and them plant them out into the garden anytime. 

You can eat the leaves and tender stems as well.  The main vines have a very sweet liquid in them, but too fibrous for human consumption... feed to animal friends. 

I love everything about sweet potatoes.

yukkuri would it be a good idea to plant what i have in a small pot and let them grow until spring and then take cuttings for planting?

Is there a difference between Japanese sweet potatoes and other ones and if so how does a person know which she has?

the ones i have are purple

You can put a sweet potato in water (I use a large mug a little shorter than a tuber.), then when the vines sprout on it and develop roots you can pull them off the tuber and plant them.  Then return the tuber to the water and it will sprout more vines.  Tubers can be stored in a cool dry place in wood shavings or such to overwinter them.  The young vines however will need to be planted or kept in water with some plant food to survive.

I would plant them in whatever pot you desire whether you take all the vines off and plant each in a separate pot or all together.  They won't be producing any potatoes unless you can give them a long, hot growing season.  If you want to grow them in a northern climate you'll need to work at it to have any luck.

Here's one way you could do it:  Go into your green house and dig a wide, deep trench.  Partially fill the trench evenly with some type of fresh manure.  You can add any type of compostable materials you wish to the manure since what you are doing is starting a compost bed that will heat your soil.  Fill the trench the rest of the way with the soil, mounding the excess over the trench.  Plant your SPs there so the combination of the decomposing manure heating the soil from below and the greenhouse heating the air above will provide enough heat for them to grow.  Additionally, if you add some barrels or other containers of water next to the bed that are painted flat black to help absorb the solar heat, they will gather heat during the day and slowly release it at night to keep the temperature more even.

Don't have a greenhouse?  Then plant them in containers indoors by south facing windows if you can.  Propagation heat mats or electric pig blankets can be used to heat them from below.  If you build self watering containers (very easy to do), you can use aquarium heaters (carefully) to heat the water in the bottom of the containers, which will heat the soil.  Then cover them with a miniature hoop house to warm the air above. 

If you don't have room by any south facing windows, you can stick them in the basement or anywhere you have room, preferably near the wood stove or a heater vent.  Full spectrum florescent tubes will provide sufficient light but incandescent grow lights will also provide heat.  And if you enclose the lights with the containers, as in a little hoop house, that will help keep them warm enough to produce.  But with the cost of electricity or other heat, unless you can use solar heating (free!), you might be better off just buying potatoes and keeping the vines as nice houseplants.  And you can still eat the leaves whether you get tubers or not.

wonderful!  I didn't know that the leaves were edible.  I have potted it up and it's sitting in a south window and looking quite happy so since space is about to become premium with other more prosaic seedlings it will likely stay a "houseplant " for the time being anyway.  Thanks for all the great feedback.

As Mwah said, Sweet Potato is grown from "Slips"
Cut pieces of vine about a foot long, you can let them root in wet sand or pots or you can put them directly in your beds. Plant these cuttings a foot or more apart. They root very easy. If you like a particular Sweet Potato from the store then just sprout one in water and you have slips to plant.
In Asia Sweet Potato vine is sold in fresh produce markets as regular leafy veg.
Excellent stir fry veg.

Pam wrote:
Is there a difference between Japanese sweet potatoes and other ones and if so how does a person know which she has?

The most common japanese variety will have a purple/maroon skin, and a white, cream or light yellow flesh that has a fluffy, mushy texture and an aroma reminiscent of chestnuts.  Korean varieties are mostly the same. 

mine are deep dark purple with white flesh.

Pam, the problem with getting tubers is that sweet potatoes need long growing time with lots of hot weather.  You could try this.  Build a nice cold frame and dig a large deep hole where you intend to install it, preferably with a good, clear, southern exposure.  Fill the hole with fresh manure and other compostable material.  It will provide bottom heat for the potatoes while the cold frame provides heat from above; heating the soil and air both.  Keep the cold frame over them the whole season and just raise and lower the glass with the weather.  Start early and continue late.

Another real nice way to go is to save some soda/beer/whatever cans and do this simple little task to have a heated greenhouse all year with no fuel costs:  http://www.youtube.com/watch?v=XsF9RvVxFc4&feature=related
 
That and paint barrels of water flat black to absorb heat during the day to keep the greenhouse warm at night.  Dark rocks or anything that can absorb the sun's heat and radiate it at night will help heat your greenhouse, cold frame or whatever.  And that can lead to real permaculture with polyculture or aquaponics where you raise all your fish in your greenhouse and grow veggies with their water and no other fertilizer at all.

I wonder how those deep purple ones compare to the ones we usually get here.

Thanks for all the comments and suggestions.  This is only one plant though!  Actually yesterday I found a nursery which DOES raise  sweetpotato slips here in Canada and will ship them about the country and it seems they have been selecting them for some years for the shorter season we have. However, they are still about 2 zones warmer than we are here so it would still be iffy; although I may take a run at it if there is some footage looking lonely in the garden. I suppose my main question had to do with whether the thing would manage to grow and thrive as a houseplant. It's really very attractive.

When my greenhouse gets going it will be hard pressed to hold everything I already have planned for it. So many projects, so little time ( and money!)....

for those who dont know, and live it very cold short season climates. you can still grow sweet potatoes to get a beneficial result, SP are very good at breaking up hard soil. in asia they use it to break up clay. anyways if you plant SP as early as you can, let them grow, vine, all that stuff. then leave them in the ground to die. the cold will kill the tubers which in turn will release TONS of organic matter into the soil while breaking up the "hard" spots. the vines end up as a natural mulch for early season weeds as well once killed by the cold. the next spring you can cover with some newspaper then mulch. poke some holes and plant whatever you want in the now very loose, fertile soil.

what an absolutely superb idea!  thank you! Now I need to look at this thing as a work in progress that will maybe pay its way with the ultimate sacrifice come next fall I'd never thought of sp as a green manure crop...

Great info, soil.  Thank you.  I'd just like to make one suggestion for one little change.  Instead of covering the dead vines with newspaper in the spring, cover them as soon as they die with a very thick mulch (Yeah, several feet thick would be very good) of organic matter such as hay or leaves.  Even better would be a massive mulch of straw and manure. 

This will break down over the fall and winter months so that you can plant directly in it this spring with it being very rich compost by then, especially if you mix your carbons - straw, leaves and such brown material - with your nitrogens - green vegetation, manure, coffee grounds, kitchen scraps - together at about a 50/50 ratio.  If you are composting elswhere, especially in containers with worms, and have any kitchen scraps saved up, mix it all in. 

If you cover the pile with sheets of black plastic to help keep it hot and keep the rain and snow from soaking and chilling it, it will break down nicely by spring and you'll have a particularly nutrient rich new raised bed.   Just be sure to allow air to circulate well by keeping the bottom of the pile uncovered by the plastic or place some objects under the plastic to keep ventilation to the pile.  Lasagna gardening under cover.

sweet potato young leaves + stem, shoots are nice to eat. Must cook or blanch in hot water to rid the poison and should not eat raw leaves. some stem eating varieties contain less poison, the hydrocyanic acid.

http://www.leafforlife.org/PAGES/IPOMOEA.HTM

yukkuri kame wrote:

Pam wrote:
Is there a difference between Japanese sweet potatoes and other ones and if so how does a person know which she has?

The most common japanese variety will have a purple/maroon skin, and a white, cream or light yellow flesh that has a fluffy, mushy texture and an aroma reminiscent of chestnuts.  Korean varieties are mostly the same. 

Pardon me for jumping into a thread which is over a year old, but I'm a bit confused over the varieties and names used.

The Japanese sweet potatoes that I used to buy in Singapore (they were imported from Japan) - was exactly the sort that Yukkuri recommended.

But the ones that I see being sold here in Australia are called Japanese or Hawaiian sweet potatos and have a tan skin and purple interior.

Purple Hawaiian or Japanese Sweet Potato - the Latin term is Ipomoea batatas | Convolvulaceae - its also known as Okinawa sweet potato.

So I'm a bit confused.

Yukkuri do you happen to know the latin term for your sweet potato?

oh wait... this explains everything

http://www.saturdaymarket.com/nakashima.htm

I am growing sweet potatoes in a large box. They grow well for about 4 months already, but the vine reached some lenght but stop growing a while ago. I know there is at least one tuber forming, on the side of the box, as I can see if I dig a bit. I dont know if there are more, probably yes. They seem to enjoy warm and lots of sunlight, and as sunlight is less now, they are growing less.

cheng cai wrote:sweet potato young leaves + stem, shoots are nice to eat. Must cook or blanch in hot water to rid the poison and should not eat raw leaves. some stem eating varieties contain less poison, the hydrocyanic acid.

http://www.leafforlife.org/PAGES/IPOMOEA.HTM

Our cut leaf sweet potato vines are taking over the garden....I have never eatten the vines except for a nibble to taste.....they make wonderful huge sw. potatoes. Does anyone agree/disagree with the above quote? I should cook the vine tips? par boil? I am not sure what variety of potato I have because they were given to me ten years ago by someone who had been growing them for years and years...as with most sw potatoes these are easy to store and easy to grow slips off of...delicious and nutritious...so if we can eat the vines too what a bonus.