If it stays above 20F, they can be left in the ground. Otherwise, when the tops die down, they can be dug up, brushed off, and placed somewhere cool and dry for the winter. If they are in a container, the whole container can be brought in and put in a basement or garage.

I can't answer your question personally about whether the single or the double is better because I only grow the double form "The Pearl." I can tell you that the double flowers gave out an awesome fragrance and was very beautiful. Here's a picture of one of mine below.

Here is a good excerpt from the plants database which I can't mention here:

"On Apr 14, 2003, Ispahan from Chicago, IL (Zone 5b) wrote:
While this plant is indeed commonly cultivated in México, it is never called "azahar" (which is the word used for citrus blossoms, especially orange blossoms), but rather "nardo" or "azucena" (azucena being the generic term for any white, lily-like flower). The tuberose was already entirely domesticated by the indigenous civilizations of Mexico at the time of the Spanish conquest, and forms of Polianthes tuberosa growing in the wild have never been discovered or seen.

There is a lot of misinformation circulating about this plant, so be wary of your sources. Basically, it needs warmth, sunshine, well-drained soil, even moisture (don't overwater but don't let it get bone dry either!), and at least a month and a half of good growing AFTER it is done flowering if you want the tubers to produce flowers the next growing season. That is where most northern growers fail with them, since they tend to bloom rather late in the season anyway. In any case and no matter what the climate, they are enchanting when grown in LARGE pots (perhaps three roots to a 10" or 12" pot) that provide ample room for the vigorous root systems and allow for sufficient expansion of the tubers. Since plants grown in pots tend to be warmer than those grown in the ground, they often bloom a few weeks earlier as well. When grown correctly, the tubers multiply at an astonishingly fast rate and you will have an ample supply to provide blooms from year to year. Oh!, and they must be divided AT LEAST every three or four years, otherwise the blooms will fizzle out.

I prefer the single "Mexican" tuberoses over the double ones called "The Pearl." The doubles can't hold a candle to the singles for elegance, intensity of fragrance or ease of cultivation (in my experience, the doubles tend to be a bit fussy)."

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My tuberose(pearl)did good this year. In October I brought the pots inside and moved them to basement. In Feb I see greens coming up that's when I start watering and move the pot to lighted area and move the pots outside in May depending on the weather. They have been doing good in pots for past 2 years. It is too cold to grow them in soil in our area. Here is one of my picture taken in October.

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the single form is used to make perfume! I didn't notice any difference!

Hi I think they are hardy in zone 8. A friend of mine who grows tuberoses for cut flowers here in zone 7a digs them up, lets the foliage dry, cuts it off and then stores them in dry peat moss or dry cedar shavings, in a cool basement.
She grows the singles.

I grew both single and double because when the blooms were done with one variety, the others were yet to open. I didn't notice a difference in scent. I would feed them bulb-building food after blooming was finished, dig them up immediately after the first frost, dry them a bit and store them in a dark, cool place indoors over the winter. However, the roots were so tough to wrangle free, I gave that tradition up after a couple of years. If you can store them in the pots, more power to you.

Hello,

I am zone 7. I have had Double and Single Tuberoses in the ground for at least, 12 plus years.All I do is mulch them. Last winter they stayed Green. This year the foliage has died back.
Fragrence, I see no difference between the two. I like my Singles Planted where I see them. As they are truely Humming Bird Magnets.The Humming Birds, do not feed,from the Double ones. For Cutting: I find more Beauty in the Double Ones.

Wow, fantastic photos. I bought two tuberose tubers, dry, last spring. I potted them and over the summer they put on a nice, healthy rosette of foliage, but no flower spike. I kept them in the greenhouse and the leaves have just about died off. As they didn't flower, what about the six weeks post-flowering rule? Can I expect some flowers next October? I can hardly wait! I haven't investigated the pots to see what the tubers are up to but will pot on & feed around late April- I recall that they were late to come into growth.

GN, I bet they will flower for you this summer. Just make sure that they are getting full sun and feed them and put the container out as soon as all chances of frost have passed.

I'm with ChooChooGal on this one, in zone7 and never dig my tuberoses - been in the ground now for 3-4 years with no issues. We have very dry winters here in NM though, which may make a difference, and I mulch well with my fall leaves. I have singles and doubles and both smell great!