As with many other kinds of trees these grow up at first then out later - nursery sized plants are much too young to be trying to impose a mature crown shape upon them. Because you are expecting them to already have one.

Ken - Alexandrina is 5-6 feet. Has one main trunk that out branches after about 4". The species is about 18" tall, very small.

Embothrium - Are you saying that this species cannot/shouldn't be trained or that people simply don't do it?

i dont see how you start bending a 5 to 6 foot tree/shrub .. until its roots grab hold.. and will offer resistance to said bend ...sooo..same answer ... wait a few years ...

i suppose you could splint new soft growth in some direction or other ... maybe some copper wire like the bonsai peeps ...

i really dont understand what you are wanting to do ... but dont let that hold you back.. i have never seen an really cool.. out of the ordinary plant... that wasnt manipulated by some dude with a vision .. so .. go for it ..

ken

Brent, can you explain in greater detail what you are hoping to achieve? I don't understand what you mean by "trunks to grow in a more pendulas manner rather than straight up?" Typically, it would be branches that are pendulous or drooping/weeping, not the trunk.

And unless one is indulging in bonsai - a wholely different concept - I have a tough time with attempting to manipulate trees into a form they are not inclined to assume naturally. It seems so contrived.

Gardengal trunks was a typo. I did mean branches as you suspected. Now, the branches have a little curve but quickly climb straight up. They'll start to lay flatter with age (think live oak), but with our short growing season I'm not sure my wife and I will be alive to see that lol. I know some people manipulate magnolias into single trunk trees by pruning, just wondering if training branches was ever done successfully.

How about a picture? I’m not following ‘the species is 18” tall’. Bottom line, Magnolia x soulangiana doesn’t need any training or even pruning if sited where it has sufficient space. Alexandrina doesn’t have a pendulous habit so it’s going to be an exercise in frustration to try and force it into one.

Name 'Alexandrina' has been used since the 18th century so multiple different cultivars have been circulated. However when material is so-called it does carry an implication of a tree-like habit, with an elevated crown.