If you are that concerned about accurate visual description why not purchase an Aira gift card? Aira is a professional visual interpretation service for the blind. Their agents are specially trained in how to vest describe visual information in a way a blind person could understand. I’ve used the service to accomplish many visual tasks.

Otherwise hiking is more than just visual. I love hiking for the exercise, smells, and sounds of the environment. I’m sure your husband will be happy just to spend time with you. Have fun!

Don't put pressure on yourself and try your best. Try to read his reactions to anything you describe and you can also directly ask what is useful and what is not. The visual experience is not the only experience of walking through the mountains and your husband may also just enjoy the sounds, smells, and tacticle sensations, plus spending time with you.