“I have a question about the yam vines…. I used 7 foot tall tomato cages (I made myself) that were not being used and the vines have reached the top already…. Do I trim them? Do I let them reach for the sky? Being that the yams will take several months or even more than a year I am not sure what the protocol is”
Yams are crazy climbers. I’ve seen them reach the top of a 60-foot tree.
Yet they don’t need the kind of height to make good vines. A 6-7′ stake in full sun is good enough.
I don’t trim the vines. Instead, I throw them back onto the stake and let them keep climbing over each other in a big mess.
When the vines go dormant in winter, dig away. You’ll see the leaves yellow and the vines start to die back. Main tuber formation happens late in the year, so don’t dig them before they go dormant – they’ll be pulling in sugars until the last weeks. If you dig a yam right now, you’ll get almost nothing. Dig that same year in a few months when winter arrives and you’ll have a nice, fat yam.
Here’s what my yam beds look like right now:
Just sticks and sticks and sticks.