Is it normal for some of the canes on a dumb cane to lay over?
These two do it regardless of being wet or dry......

I guess that's why it's called a dumb cane Jokes aside I see that a lot in other photos so I'd say yes.

@ediblelandscapingsc
:biggrin:

Yes, I've seen them do this too. They're "reaching" for more light, out from under the shade of the mother plant.

You could cut them off when they do that if you don't like the way it looks. Just stick the cutting in some potting soil in the shade and keep it moist, and it will probably root, too. You might even be able to separate the flopping stems with some roots attached, which will give them a big boost on getting established as their own plant.

They should root easily from cuttings but misting is a full time job it's easier to remove all the leaves except the top 2 and cut them in half then place a cut 2 liter bottle over it with the cap on. This keeps the moisture in the air around the plant always then in about 2 weeks loosen the cap. in another week remove the cap. 2 weeks later remove the bottle and voilà a new plant
you can see how I use the bottle trick behind the grafted persimmon in the foreground.

Dieffenbachias have large, heavy leaves that invariably reach a point where the stems start to lean and may even snap off. The only solution - other than unsightly stakes and other supports - is to prune the stems back whenever they become unsightly or unwieldy. Pruning will promote healthy new growth from just below the pruning cuts and will never harm the plant in any way.