If I plant a bunch of morning glory seeds in a big flower pot (WITHOUT A TRELLIS OR SUPPORT), what will it look like?
Will the vines just wrap around each other and spill over the sides?
Will I just get a massive messy tangle?
I have hundreds of seeds leftover from last year...should I just try it and see?
I am new to morning glory...However I suspect that they would not fare well at all. They will more than likely climb on whatever they can find that is close by...if the little shoots don't die first. I have noticed that my MG's that are farther away from the trellis tend to crawl around on the ground looking weak and sad. The shoots are smaller. I have to check them every morning for new growth to see if I have enough there to train them to a point of attachment. Once they have established a good hold they take off nicely.
There are some I. nils that are weeping types and there are some for contianers like Cameo Elegance that don't get too big, kind of bushy, very nice. Other than that, the I. purpureas will do exactly what Lilyofthenight said, they will climb on whatever is close to them or onto themselves.
Put a couple of bamboo sticks and make a teepee, even a tomato cage would work.