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KitchenGardener
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Sweet Potato Questions

Hi all:

I did start by searching sweet potatoes and reading all the threads I could find here, but want additional info, if possible.

I have never grown them but would love to. I live in an excellent climate in Northern California. These days, it seems that average daily temps during June - October are most often in the 80's with night temps not below 60's. Today, temps in my back yard were high 60's with night temps probably hitting low 50's.

I love the idea of growing sweet potatoes in a big round bottomed ceramic pot. The pot is at least 3' across and about 2 1/2 ' tall. Right now, there are potatoes and peas in the pot, but the potatoes are just about to finish and I thought I could amend the soil, and then add a sweet potato or two. I also read how someone suggested that every four feet, you cover the vine with soil, so it will take root and produce even more tubers at these locations. I'd be growing it in the big pot as an experiment. I don't have room in the garden for such a space consuming plant, and don't want it to take over my yard. Can I grow it in the big pot and just take what I get? That is, forego any additional tubers I would get by burying the vines outside of the pot? I just don't know where I'd bury them, as I have a ton of pots (all on concrete), a garden patch area (too small to accommodate sweet potato), and a lawn area. Not sure I want the vines growing into the law and taking over either.

So what do you think? Could I grow them in the pot after removing the potatoes and limit the tuber production to the pot itself? Is the weather adequate here? How hot does it really need to be? We are having more and more occasional days in the 90's, but its not consistently that hot - is that a deal breaker?

Thank you so much!

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Lindsaylew82
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I think if you keep them adequately watered, the heat is fine. We get consistent temps in the 90's for 4-6 months of the year where I live, and sweet potatoes do perfectly here!

My kid's class has this little 4'x4' rolling indoor planter that's about 6 inches deep. They grew a sweet potato in that thing all last year with an avocado seed. They pulled out 3 HUGE sweet potatoes! I could not believe how big they were! I thought for sure they were going to be finger sized at best, but they were truly huge! They were inside the entire time as well... I can't say as to if that is the norm, I'm sure it isn't, but I think if you keep them maintained well, you should get a decent crop.

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Gary350
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FORGET the idea of growing sweet potatoes in a pot if you want lots of good potatoes.

When you plant a sweet potato plant it grows several vines and the vines go in all directions and will cover a 50 foot diameter circle. The vine take root and provide more water and nutrients for the plant. Each place where the plant takes root will grow more potatoes at each satellite spot. The mother plant will produce about 30 lbs of potatoes and each satellite spot will produce 8 to 10 lbs of potatoes. Cover the vines with soil every 3 feet to make the vine grow roots there. 1 plant can become massive and produce 125 lbs of potatoes. I use to plant 3 plants 3 feet apart and restrict them to a 50 foot circle by cutting off anything past the circle with the lawn mower. Now I plant 1 plant in the center of a 50 foot row and make 1 vine grow in each direction, I cut off all the other vines. Sweet potatoes love hot weather, full sun all day, they do not care how bad the soil is but will do better in better soil and do better with fertilizer and more water. Let the plants grow until frost or freezing weather kills them. Keep out all the grass and weeds.

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KitchenGardener
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Thank you both for your replies. Its worth a try since I wouldn't want to leave an empty pot (gasp!). I guess I'll just try and keep my expectations low. Lindsay, so cool that your child's class was so well rewarded for their efforts. I'm not sure I have the heat, but I'm game and hopefully will report back.

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You can grow sweet potatoes in a pot , I actually use a tree pot or large tub. Gary is right though the vines will keep spilling out, however, not a bad thing. Sweet potatoes are not nightshades like regular potatoes they are actually related to morning glory so the leaves are edible. Some taste better than others and locally people grow a sweet potato vine just for the leaves since it does not produce any appreciable tuber. Cutting the vines reduces tuber size, but if you leave it in the ground for at least 180 days they get pretty large.

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KitchenGardener
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Imafan: are you saying you don't get sweet potatoes where you are, but only leaves? I thought you were the HQ for sweet potato growth!

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KitchenGardener wrote:Imafan: are you saying you don't get sweet potatoes where you are, but only leaves? I thought you were the HQ for sweet potato growth!
He is saying thats over there they commonly grow a special variety only for its leaves. Other varietes for tuberformation.
Its a tropical plant so hes in the right zone alright.

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KitchenGardener
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Oh gotcha, thanks for the translation! :wink:

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I grew sweet potatoes last fall and recently just harvested them. I have very poor hard soil with limited space so I grew them in homemade grow bags and a large tree pot. I did neglect them a little so they came out kinda long and skinny rather than short and fat but they taste just fine! Some funny shapes from hitting the wall and turning I guess. Also with the vine I kept it inside the pot for the first little while and kept covering the leaves with soil. Once the pot was full I allowed the vines to hang outside the pot.

Image
Image

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kayjay
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Those look cute! I'd actually be happy with small sweet potatoes like that, because they're pretty much single-serving. I eat alone a lot; I'm not feeding a family.

KitchenGardener, go to youtube and do a search on "sweet potato container harvest". There are quite a few videos showing successful container sweet potatoes. It's definitely doable. I have an old 20-gallon Rubbermaid tub I might try it in.

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Lindsaylew82
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Someone here used to grow sweet potatoes in Tupperware tubs! Was very successful, too! He would post videos of him harvesting them with his dog. That dog was a HAM!

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KitchenGardener
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Thank you all for your replies! So, having never grown them before, I assumed that I could go to a local nursery and get seedlings. Nope! So Plan B: I bought two types of organic red fleshed sweet potatoes - I think one might be "jewel" and one might be "garnet" (or maybe I'm just throwing those names out because those are the varieties I typically buy to eat). Anyway, they're currently suspended over/in jars of water, and I'm hoping to get some slips in a few weeks' time.

Question: I've been avidly reading about growing them and came across something that said that sweet potatoes need night time air temps no lower than 60F. I see that according to online temp charts, the average night time temp here in Summer is 58 F. Is this a lost cause? I'm planting it in a big planter not amenable to being brought in at night. I'm still doing it as I love to experiment, but still, don't want to undertake it if there's no hope whatsoever...

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Lindsaylew82
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I say, what've you got to lose?!

imafan26
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I am coming back to this topic late.
We grow multiple varieties of sweet potatoes. The Filipino sweet potato is grown for the leaves and they don't make much tubers. The other sweet potatoes we grow are usually the Molokai sweet potato one is red skinned with a yellow, sweet flesh, the other is gray or white skinned with purple flesh and t is not as sweet and it can be drier but actually is the more popular one. There are some other varieties as well. Most of these sweet potatoes will make tubers but if you keep picking the leaves they don't make a lot of tubers.
https://www.rareseeds.com/sweet-potato-m ... ril-june-/
https://islandbreath.blogspot.com/2008/1 ... otato.html
https://www2.hawaii.edu/~hector/prod%20g ... otato.html
Usually we don't plant the sweet potato tuber. You allow it to sprout or you plant the cuttings from the vines instead.

https://www.ncsweetpotatoes.com/sweet-po ... -potatoes/

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Gary350
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I like to plant sweet potatoes April 1st and harvest 7 months later when frost kills the plant. I once grew a 13 lb. sweet potato the size of a soccer ball it was lumpy looking like a dozen potatoes all grown together.

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KitchenGardener
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Gary350 wrote:I like to plant sweet potatoes April 1st and harvest 7 months later when frost kills the plant. I once grew a 13 lb. sweet potato the size of a soccer ball it was lumpy looking like a dozen potatoes all grown together.
My first impulse is to say "Eww," but thought I should ask - did you eat it and was it any good?

imafan26
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We grow the sweet potato and eat the leaves, the tubers are a bonus. It is a long crop especially since we don't really count we just decide to dig it up. This is an old publication but still relevent. It says that if it is colder it will take longer to produce tubers. You cannot let it freeze.
https://www.ctahr.hawaii.edu/oc/freepubs/pdf/B-50.pdf

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Gary350
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KitchenGardener wrote:
Gary350 wrote:I like to plant sweet potatoes April 1st and harvest 7 months later when frost kills the plant. I once grew a 13 lb. sweet potato the size of a soccer ball it was lumpy looking like a dozen potatoes all grown together.
My first impulse is to say "Eww," but thought I should ask - did you eat it and was it any good?
I don't like to eat sweet potatoes but I do like sweet potato casserole for Thanksgiving dinner. I like growing sweet potatoes it is a challenge to see how many lbs I can grow from 1 plant. I donated the whole 130 lbs of sweep potatoes to the homeless shelter 2 weeks before Thanksgiving.

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KitchenGardener
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Gary350 wrote:
I don't like to eat sweet potatoes but I do like sweet potato casserole for Thanksgiving dinner. I like growing sweet potatoes it is a challenge to see how many lbs I can grow from 1 plant. I donated the whole 130 lbs of sweep potatoes to the homeless shelter 2 weeks before Thanksgiving.
Awesome - you set a good example for me, were I ever to get an abundance of anything.

So my next sweet potato question: how long do you try to grow slips with nothing happening before you chuck the potato and start over?

I bought two types of organic sweets. I perhaps wrongly assumed, due to the high turnover of the market in which they are sold, that they had not been cold stored or had anything done to them that would inhibit their ability to grow slips. But its been 19 days with them soaking half in and half out of jars of water, and one has two baby slips and the other has absolutely nothing - or so it appears. I change the water frequently. They've been sitting on a kitchen window sill. What do you think?

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Gary350
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I bought a sweet potato plant at the garden center last week. There was 9 slips growing out of the pot. I only wanted 1 slip but had to buy the pot for $3.50. I cut it in half and planted them both 2 feet apart in the center of a 50 foot long row. Once it roots and starts growing I will cut off all but 1 vine growing East and 1 vine growing West. My garden is 1 1/2 months behind schedule because of bad weather. I hope to have 100 lbs of potatoes when frost kills the plant about November.

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KitchenGardener
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Well I tried, I really did, but had my first fail of the season. Started multiple sweets in water hoping to get slips. Got little nubbins and one slip, even with my several attempts at varieties and window sills. The sweets kept rotting. Anyway, broke off the one tiny slip (one set of leaves) and folded its bottom half carefully in wet paper towels and watched its roots grow...a tiny bit of additional top growth made me think I could try planting it, so planted in a mix of vermiculite, compost and a bit of sand. I gave it time to get over its shock and waited for it to grow, and it did so ever so grudgingly. But then its tiny, baby leaves started yellowing ever so slightly, and I decided it was a goner, so I pulled it up expecting so see no more roots than when I planted it, but there were some longish roots! And then I kicked myself for letting my curiosity get the better of me.

In my climate, I doubt it would've made it anyway, but sheesh, silly me. :roll:

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applestar
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Well you could have put it back. Sweet potato is pretty sturdy. ABSOLUTE KEY to growing is heat, Heat, HEAT. 85°F or above. 90°F would be better. Once it gets hot enough during the day, direct sun will provide the kind of heat you need. No A/C -- set up outside or garage or attic... Maybe your car parked in the blazing sun.

For me growing the slips is not the problem, it's the typical lovely cool night air in the 60's and threats of early killing frost and accompanying drops in temp starting around late September -- I can't count on heat-loving crops beyond then even if the subsequent days are frost-free until late October or November.

This year, late lingering cold spring delayed everything so I'm not very optimistic about sweet potatoes, but I put this extra late Hawaiian sweet potato in last year's eggplant SIP after the big broccoli were done.

Image

...if this works, I might have to concede that I have to grow sweet potato under black plastic mulch when planted in the ground, and plant the slips earlier by setting up a low poly tunnel over the black-plastic mulched raised mound.

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lakngulf
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I agree that sweet potato plants are pretty sturdy. I planted some beautiful starts in between two rows of tomatoes at my Mom's garden. Then we had issues with Groundhogs. First they hit her cucumber plants and then started on sweet potato, clipped them to a nub. I put electric fence around the entire garden, kept them out so far, and the sweet potatoes have taken off again. Here's hoping.

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Nice! I love hearing stories of nature - in this case sweet potatoes - prevailing. I really think the weather here is just not conducive to them since it seems that every night it dips below 60 degrees.

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I tried and failed at growing these a few years ago, but I'm game to try again next summer (I'm out of space for this season already, and I'd be late anyway). *

For those of you with heavy clay soil, do you double-dig? Or how much tilled depth do these require for good production?

Do you cure them before harvesting? Bonnie's suggests that you do.

* or maybe not! I just checked my records from 2012, and I planted the slips on July 19! Maybe I can find a spare spot in the garden . . . .

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Lindsaylew82
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I have pretty heavy clay, and I did not double till. I would suggest waiting until your clay is dry, otherwise it get clumpy. (At least here it does, and it's very hard to work that out once it dries that way!)

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rainbowgardener
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So I have a sweet potato half that has been sitting in water. It has a lot of roots at the bottom and a couple vines with leaves starting at the top. Not as many vines as this, it's just a picture I found, but this general idea:

Image

All the instructions I find say I should pull the vining sprouts off the potato, put them in water for awhile to grow their own roots and then plant them. Is there any reason why I can't just cut the sweet potato in chunks, like I do regular potatoes, each chunk with some vine and some roots and plant them?

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applestar
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I have settled on rooting the slips pulled from the potato (started in water) in Dixie cups of potting mix. Works better than water imho.

Never tried planting the cut up sweet potato but I would be concerned that they would attract vermin like chipmunks and voles, wireworms, etc.

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I had 2 sweet potatoes in water for months; maybe 3 or 4 months (which seems ridiculous) but finally after all that time I have some slips. Had to keep adding water of course. But now, putting some slips in their own water, or into little pots to form their own roots; I mean, I'm thinkin by the time that is all done and they're ready to plant, it will be winter! They need a long growing season once in the ground, no? :) What to do? :)

Maybe next year I'll just buy something from the garden center like Gary said!
Never seen them there, but never really looked for them either.

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rainbowgardener
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Well I don't seem to have any chipmunks or voles in the neighborhood, so I think I will try it. I'm with Taiji, I want to get something planted!



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