How deep do I plant the seeds, and do I build a string trellis like with a pole bean?
Certified GKH Gardening Expert
As with any seed, you will want to plant it twice as deep as the seed is wide. This is a good general rule to follow for most things.
These vines can reach about 20 feet in length, and a trellis would be a great idea!
This article will give you more information about the plant: https://www.gardeningknowhow.com/edible/vegetables/jicama/growing-jicamas.htm