The best time to plant a southern magnolia in the "North" is in spring or summer, so it has enough time to develop roots before winter. You can try planting it outside now, but you are probably taking a chance... If you have a mild winter, it will be fine. If it is a severe winter, it could suffer serious burn or dieback. I'd probably keep it outside until you it gets cold, then bring it inside or somewhere that will get some light for the winter and preferably remain somewhat cool... I usually put stuff like that for spring planting in my garage next to the window

Nah I think it would be okay! Southern magnolia's depending on which size can be very hardy tree's We have a really big one in our back yard and its seen some cold days with no stress they generally loose leafs in the fall and once again in spring its really wierd so the rake is always ready its kinda a pain but is really nice to see blooming may thru aug magnolia grandiflora is a strong tree I say give it a try planting it on the southeast side would ideal for winter but even without should be fine I assume

Thanks for your kindly advises. I don't have a window in my garage. I'm going to plant it soon.

The one I got is Southern Magnolia. The seller told me it could grow up to 90' tall and 40' wide. Do you think it will grow that tall and wide in zone 5? I havn't seen a grandiflora magnolia taller than 25' in my area. I hope it could keep around 30' tall and 20' wide. I was going to use it as a screen between my kitchen window and the neigbour's fence, about 30' distance. Now I'm afraid it may grow too big for that space later. I think I got a wrong tree for my purpose.... Any suggestion?

In nashville there are some that tower over house's 90 feet tall probably 100' By the time it gets that big hopefully we are 6 feet under the ground haha usually when they grow to that size magnolia grandiflora is a grown adult and can withstand anything but a tornado usually about 200 years old we have a bunch in tennessee everywhere at andrew jackson's house in the hermitage to the state capitol in downtown nashville and even parts of east tn in the mountains also zone 5's in my opinion the hardiness zone is the most extremes of cold ive lived in a hardy 9 zone in north florida and every winter it got pretty cold mainly at night in jan but didnt stay that way but for maybe 2-3 weeks we are going threw global warming so its about time the hardiness zone changes it usually does every 10-20 years I think by the usda 50 years ago we would get snow up to are knees the native nashvillians have told me now we are lucky if we even see an inch it never snows i remember snowstorms when I was in grade school that would keep us out of school for weeks Nashville is a good oasis for all the season's though not to hot not to cold very humid climate I can send you some magnolia seedlings if youd like I have plenty ha in the back yard and mimosa magnolia grandiflora are quite common throughout the south mimosa's are easily spread all over almost like a dandelion weed

Not to be argumentative, but zone 7 Tennessee is totally different from zone 5 Kansas. You can't make the assumpion that just because a plant is going to thrive in Nashville that it is going to thrive in a colder climate. It's much like saying that a sago palm in zone 9 is robust and healthy in Charleston or Savannah, so thus it will be robust and healthy in Nashville- far from true... Kansas is flat and thus, the cold winds can sweep through without a buffer from the many hills and forest areas which are common in Tennessee. Your southern magnolia will never attain a great height like the "grand dames" of the South. It will though top out around 30 ft or greater if sighted properly and given some protection. You also can not plant jusy any magnolia grandiflora in zone 5/6 and expect it to live. You have to plant a hardy variety... something along the line of "Edith Bogue," "Bracken's Brown Beauty," "DD Blanchard," and possibly "Little Gem." There are also some VERY hardy selections, such as "24 Below" and "Poconos" that are very hard to find commercially, but would be superior in hardiness to the ones I first mentioned. Even the hardiest varieties can experience significant winter burn and stem kill until they are well established.
Though Nashville can experience cold temperatures around 0F or lower, these temps will not be sustained like would be the case in KC. You can go for a week or two with nightly temps hovering around 0F or lower in KC, while you may have only one or two nights in Nashville at or below 0F. Duration of cold (temps below freezing... ex. 0-10F) can be much more damaging to broadleaved evergreens than one night of extreme cold (ex. -10F). But the absolute worst thing is winter wind and sun. If you do plant it this fall, mulch it well, apply an anti dessicant spray, such as wilt-pruf in early Dec. and early Feb. and just for extra protection try wrapping it with a burlap screen, to add a couple of degrees. You may even want to do the same next winter, but after one or two winters, they will generally acclimate themselves to the conditions and eventually no protection will be needed.

Well it is rarely 0-5 degrees even. Usually it drops to around 15 is about the coldest a hard winter is 0-5 degrees but its been a while since we have seen that. I dont know how extreme kansas city may be. Southern magnolia's adapt well I dont think it would hurt to give it a try. Magnolia Grandiflora is said to be hardy to 0 degrees anything under 10 while it is young I would give protection to just to be on the safe side.

I live in central Illinois at the border of 5a/5b. I have a BBB growing on the northside of my house. I planted it in the summer of 04 and it has done great actually here. I do lose leaves towards the end of winter but even after several weeks of sub zero weather this past winter my magnolia still had most of its leaves. Browning didnt occur until it warmed back up. I still had leaves at the end of the branches and no damage to wood. I took a different route rather than protecting from wind, I protect from winter sun. It doesnt need direct sunlight if its really cold out, the plant wont want to be forced into too much thinking. These low temps in the winter of 06-07 were during a period of strong winds and blizzards. This spring it flowered well and few nice and green. -7 is the lowest temp weve seen here in over 10 years. Probably 1994 was the last severe cold snap where we did actually get to -12 below or so. I know others that have had relative success with Edith Bogue and BBB here in central Illinois. I kind of get confused by all these super cold temps down south I heard about over this past winter because we didnt get as cold as they say they did down there. Mother Nature never surprises me though completely. Temperatures have been warmer in the last 30 years than previously. Ive seen full grown Mimosas in some peoples yards, not that it would take them long to get there.

Obviously doniki has never been to Kansas and cites the stereotype of the "flat" Kansas which is not true at all. While we may not have the mountains of East Tennesse, Eastern Kansas is full of hills and valleys and is heavily wooded while the mid to western part of the state is rolling plains. Some areas are definitely flat, others are undulating hills, particularly the Flint Hills from the Oklahoma border to Nebraska. Anyway, there are a number of examples of Magnolia grandiflora growing in the Kansas City area and have been for many years. The difference, as doniki pointed out, is that M. grandiflora seldom gets more than 20 or 30 feet tall in Kansas and will periodically suffer from some freeze damage when we get our periodic below-zero weather. When I lived in the Ft. Walton Beach, FL area many years ago, M. grandiflora was indeed magnificent, reaching heights of 90 feet or more with huge blossoms. Absolutely impressive! These trees are indeed grand. But, yes, they can be successfully grown in Kansas. If you can protect them from the north wind because you are out in a wide open space, I would put them where they are somewhat sheltered but the older they get, the hardier they become. I have a Vitex agnus-castus growing in the yard that has been there for over 14 years, started from seed. It's not impressive like the "tree-like" V. agnus-castus in Mississippi but it forms a nice big bush and provides us with beautiful lilac-like blooms in mid-summer. Same thing with our crape myrtles. They're not as impressive as the ones in Memphis, but they still provide beautiful blooms in the summer. Don't be afraid to grow out of zone. You'd be surprised when you can get away with!