I've been growing them for several years. I originally purchased mine from One Green World and have been very disappointed. They are very easy to grow and very easy to propagate, in fact, highly invasive in zone 5. My plants are all derived from the initial seedling, but produce very little fruit, only a few a year. I have been trying to figure out if it is a problem with it not being as self-fertile as most, if it is an issue with not the right pollinators in my area or just a poor seedling. OGW said they were self-fertile.
I would be interested in trading cuttings with someone to help me investigate what the issue is. I've read that they like to be kept cut back strongly to encourage fruit. I've been digging out and destroying much of my plants the past two years. They start very easy from cutting, even in water, but I get the best results with cuttings in soil in a pot.
Regarding fruit, the berries turn red long before the fruit fully ripens. Red fruit, before fully ripened, reminds me of a poor tomato in taste. However, left on the plant until they start to soften greatly improves the taste and also adds significant sweetness. Takes about a month or so after they turn red. For some reason, the birds don't bother them much here. Plants flower all summer long for me, but only set fruit as the weather starts to cool into fall. I pick my few fruits just before first frost.
Vines get big and are very unruly. They also have thorns. I mostly just buy the dried fruits, when I can find them with good quality and not too expensive. There have been some reports that imported dried fruits may have been contaminated with lead or other chemicals, so I'm pretty careful where I get them and don't buy too many lately.
