There really isn't enough information to go on.
Not knowing it it was planted properly, irrigated when necessary, or given something potentially harmful like a root booster or herbicide overspray, I will give you the most positive outlook that I can and say it's probably just transplant stress and possibly some winter injury. (yes even though they are native to your area).

Magnolias are slow to establish and slow growers even when established so don't expect much growth for the first few years.

A little more information and some pictures might help determine, what, if anything, is wrong.

how big was the root ball on this 6 foot tree??? ... if we presume the tree is twice as big underground.. as above.. you might consider that 90% of its root mass was cut off ...

ergo ... the move stressed it ... aka transplant shock ...

when did you plant it.. at the proper planting time???? very early spring???

how did you plant it ... amend the soil??

what was your watering protocol ... what was your summer like weather-wise.. drought???? .. extreme heat????

did you mulch it ...

but frankly.. it all boil down to this ... its still alive .. so what are you worrying about ... lol ... 2 to 3 years to get fully re-established ... and it should take off and grow normally ...

when i move just about anything.. though i check dampness religiously [yeah right.. lol .. do as i say.. not as i do] .. i really dont come back for 2 years.. and expect anything but the thing being alive ... and if that is the case.. i win ... the show will come later ...

more facts please ..

ken

ps: btw ... on an evergreen.. of which i have a lot of experience with conifers .... the injury .. could have occurred.. way back at transplant.. but being literally EVERgreen ... it dos not SHOW until much later ... and up here in the great white north.. that is usually winter ... it went thru a period.. of absolutely no water [and that is why i ask about WHEN you did it].. while the roots were being insulted... and now you are probably seeing the effect ... what it is really all about.. is next years buds ... and if they are fine.. the plant will live ...

Impossible to say with info given. My default is improper planting.

Dan

Come on, give him the benefit of the doubt.

Ok, great follow ups. I planted in early January. The pot the tree was growing in was small for its size and when I removed the pot (which had to be cut off with tinsnips since the roots were so wound up) I discovered a tap root that was going around in circles. I did my best to free it by snipping some of the hair roots that confined it and loosened some of the hair roots on the side of the root ball.

I dug the hole twice as deep as the root ball. I put some fertilizer in the bottom to encourage root growth in that direction and then covered with with good soil mixed with a bit of sand. The soil beneath that was a hard clay. The top of the rootball was above the ground level. I covered with pine needles.

This past summer in North Carolina was the hottest on record and I tried to water but I doubt I kept up with its needs in that kind of extreme heat. The heat/ drought was a good point that I forgot happened last year.

Based on this information, can you guys/gals suggest a good watering/ fertilizing schedule for this little guy? Hopefully, this year will not be so hot!

Unless there was significant cold before it took root burning of leaf margins would be the heat/drought and/or mineral salts in the soil, perhaps from the fertilizer.

"I dug the hole twice as deep as the root ball. I put some fertilizer in the bottom to encourage root growth in that direction and then covered with with good soil mixed with a bit of sand. The soil beneath that was a hard clay. The top of the rootball was above the ground level. I covered with pine needles. "

Did you mean DEEP or WIDE here? Hoepfully not deep, the bottom of the hole should be pretty much undisturbed to discourage settling. Also even though the top of the root ball is above ground level its a good idea to make sure you can see root flare. Also since it sounds fairly potbound you can vertically slit it in 3 or 4 places before planting to help with the circling roots. And adding synthetic fertilizer to new plantings can burn them as well and cause additional problems. Mulch several feet radially from the root ball it will help by adding nutrients to the soil and thereby encourage lateral root growth and unless your soil is lacking in something proven by a soil test this will eliminate any need for fertilizer. Also if soil is the least bit moist it doesn't need watering yet. Symptoms could be caused from anything the other posters already mentioned and in that case good luck treat your plant right but don't over do it -hopefully it will be fine by mid-spring.

BHTX936:

It was both twice and deep and twice as wide. However, I backfilled the bottom of the hole with good soil mixed with sand. I did this because I wanted the roots to be well established before encountering the hard clay layer that is a characteristic of this area. I filled the hole to the point that the rootball was above ground and then covered.

"where the Southern Magnolia (magnolia grandiflora) grows wild and in abundance. ... I planted a small tree ... from a reputable nursery"

Another possibility: the nursery was selling a non-local plant not well adapted to your local conditions.

Resin

I guess BHTX936 covered most of what I was going to say after reading your second post. Below is a link to my guide for planting trees and shrubs. You might read through it for future planting endeavors.

I will say that your description of the rootball of your tree doesn't seem consistent with what I'd expect from a reputable nursery.

IMO, provenance is unlikely to have much to do with the problem, given your location.

Here is a link that might be useful: Planting a Tree or Shrub

Like I said: my default is improper planting.

Dan

But I can go with poor stock as well. Provenance might hinder with given planting and weather and stock.

Dan

Pot-bound etc. stock is pandemic in contemporary commercial practice. Big famous operations that trumpet their superior methods and quality routinely crank out truckloads of trees and shrubs with TERRIBLE root systems. Although the greater need for aftercare has been a turnoff I am moving more in the direction of planting mostly herbaceous plants just for the one reason alone that woody plants offered pretty much always have crap roots.

I can work with circling roots but kinks are a non-starter, which usually come when very young. The BH purchases hundreds of trees a year so we get better service than most, so any woodies I buy I take out of the can and look at the roots right in the nursery if I can't get them to set some aside for me. I enjoy the looks the other customers give me and once in a while you get a teachable moment.

Dan

Severe deformities right at the base of the trunk are frequent, these are due to overly long spells in small pots or bands, without any rectification occurring when the stock is bumped up. Enough new roots escape the original knot to keep the top coming along well enough for the plant to be sold and shipped. However, such specimens may need stout stakes to remain upright while still in nursery sizes. This is why you see so much non-climbing material at outlets that is trussed up like vines. Later these plants may often be able to have the stake taken away and perhaps grow for decades, only to lean or topple completely when adversities such as snow loads overcome the incomplete anchorage dating back to that time in the small container. It seems planting a root-bound specimen of a tall, pole-like fast-growing species such as a gum or pine could be quite a hazard in the making.

... or being stuck roughly when very young.

Nonetheless, strong indications from info provided that improper planting is major culprit, certainly poor stock improperly planted is a poor bet for joy in summer.

Dan

I read online about a suggested fertilization schedule as March, May, and then August for the Southern Magnolia. Is this overkill for a second year transplant in the condition which I described above?

Fertilize your tree again when you have a specific indication it needs it, such as a soil test report.