I see you are in z9a, as I am, tho' the difference between California and Louisiana is amazing, so I'm not sure my advice is entirely accurate. Here my Alo. mac. has been in the ground for a few years and has never even seemed particularly damaged with our few frosts and freezes. I've heard that your lack of heat in the summer--comparatively of course--can make it harder for things like these to store up what they need to make it through the winter. Since you have off-sets, perhaps you could pot some to take in and protect as an insurance policy, and plant some in the ground. I think I have read they're hardy to maybe z7--didn't pay too much attention as it's not really relevant to me, obviously. The Aroid Society has hardiness rankings on their website. Lots of times with lots of plants I enjoy the chance to experiment and keep some inside and some in the ground when I have enough to do that.

This is such an easy question to answer. Cut the stem at whatever height you want, stick the stem into soil and step back and watch it grow. The stem will root and the leaves will continue to grow. Now cut the stump of the old plant back to only a foot in length. Several new plants will grow around the old stem. You started out with 5 plants and now you have 5 plants with leaves at the height you want and you have 5 stumps which are growing two or three new plants from each stump. You now have 15-20 plants; plenty to trade or share.

Those are both helpful hints. I appreciate your help. I had never heard of taking a cutting of a huge stalk, but here in Santa Rosa, we get cold wet winters that seem to rot everything. I would like to try that propagation method spring.