Yup. That was it. Thank you!I have planted both beans and hops with zero issues on sandy soil in SV 1.5.0 and 1.5.1
The key is (as has always been with trellis crops, this is not new) you can *not* be standing on the spot where you are trying to plant. The trellis does not allow you to stand on that square. You must stand to the *side* of where you want the bean (or hops, or grapes, or any other trellis crop) to grow when you plant the seed.