We had a hard frost last night, so I found myself harvesting yacon this afternoon. The pic below shows the harvest from three plants (3-4' tall this year!) on the seat of a 20" chair. I estimate between 15 and 20 lbs of edible tubers from these 3 plants. There is a crown (propagation part) in lower left corner just prior to bagging up for comparison.
Yacon is one of my favorite crops. Harvesting is so easy for a root crop. I just put a shovel straight down about 10" from the plant, then pull back on the shovel while gently pulling the plant up. Usually the crown and nearly all of the tubers will pop out of the ground with little effort. You can usually see any extra tubers and just pull them out of the ground by hand. Occasionally I cut a tuber or tow, but that is not a big problem as the cuts cure up OK.
I then just break the eating tubers from the crown and then trim the crown with pruning shears. I lay the eating tubers out in cardboard boxes and put in the house for curing. Curing of the tubers takes place at room temperature (and can also be done in the sun as long as they don't freeze). During curing and storage, the tubers become sweeter and the mild flavor intensifies. The crowns are stored to produce next year's plants.
Yacon is not Jerusulem Artichoke even though they are distant relatives. Yacon stores at room temps or slightly cooler in open air. JA stores under refrigeration and needs high humidity (plastic bags). JA will come back year after year in zone 5 (and can be invasive). Yacon will not survive a hard freeze, so does not overwinter in zone 5.
Yacon taste is far superior to JA as well.
I typically grow 1-3 plants each year, but we have been finding that we want more yacon because we use it up quickly, so this year I divided up the two crowns I had from last year and was able to plant out 9 plants. So our yacon crop is much larger this year. I plan to expand a bit more next year as well.
I got my initial plants from Nichols (Seeds of change offered it in the past - I've heard they had the same source), who have been offering it regularly for the past few years. Reading on the Internet has produced hints that there are a number of varieties of yacon available in South America. If anybody knows of any other yacon varieties available anywhere other than Nichols, I'd like to hear. I think yacon is worthy of growing in most gardens and would like a chance to check out other kinds, if they can be had. If this one sounds interesting to you, please check it out.
