Get the Yacon now (lift carefully by scraping away soil round the base gently - the tubers are easy to break)
Lift the Oca in about 2 weeks.
Lift the Oca in about 2 weeks.
There's a crop Mary - or there will be a couple of weeks after the frost kills the top growth -I'll bet good money on it - they have had more than long enough. There generally isn't much untill that top growth gets re-absorbed
Mary did really well - I've had huge crops in the past and certainly have plenty of tubers for next year - it just wasn't as prolific as other years.
As beachlover says though, things change year by year. This year has been great for fruit, less good for tubers. It happens.