No can do. The size is genetically predetermined. But there is a dendrobium to fit. Dens are one of the largest groups in the world of orchids. They come in all sizes. Good luck.

Hi Shirley. I am guilty of cutting those long canes shorter. I don't think it ever affected the plant. The old canes which are not going to bloom again get cut. I don't cut all of them but just the ungainly tall canes about half way.

I wouldn't try it if there are only a few canes. But if you have a bunch of old ones, I would cut them.

Jane

That's what I did Jane, leaving the new growth for the next blooms. .

Before the new growth blooms it will be too tall. So is it OK to have blooming canes full size and the rest cut back? If you have room for the new growth the you have room for the old canes. I think there are more than 1000 species of Dendrobium. At least a lot. And the number of hybrids is infinite. Without doubt there are plenty of dendrobiums that are small. Move the big dendrobium and let it grow to its full potential.