Fellenberg, I believe, is considered similar to Italian, but as I said, I never have grown it. It tends to be rated a moderate cropper. I consider Italian here less than a moderate bearer so I'm guessing Fellenberg would likely be same. There's a lot of tricks I use to accelerate bearing so I'm not sure if Fellenberg actually can't be speeded up significantly. I consider Castleton a very flavorful prune plum but what makes it stand out is its reliability- it tends to set fruit in clusters almost like grapes. Some years other plums set little or no fruit but Castleton always seems to have a crop at all sites. It is also a natural semi-dwarf with a wonderful spreading branch habit. My favorite prune plum is Valor because it is very big and has that rich super-sweet quality and it can ripen from the last week of August here until the first hard frost. That is an extremely long picking time even for a prune plum. The reason I recommend Castleton over Valor is because of its consistency at many sites I manage. The funny thing is that at some sites plums are generally much more reliable than other sites for reasons I've never been able to decipher. That means that to really know what is best at your site you'd have to try several varieties and find out yourself but if you're just going to try one I think Castleton is your best bet. ACN carries it but you'd better order ASAP because the commercial growers are sucking it up.

You didn't mention what nearby loaded fruit trees are. Are any of them European plums providing cross pollination? Self-fertility is relative and even varieties that are heralded is such are often marginally so. I actually find Italian plums to be unreliable croppers here in southeastern NY, even when surrounded by compatible pollinators. Some sites get moderate production but on my own property I've one that has never given me a decent crop. I just keep it to help pollinate a Valor that I originally planted in the same hole.

I often see fruits coloring up early, when small or immature, if they're under stress from insects or weather or disease. I get a lot of late PC damage on my plums, and they drop like rain, barely larger than the pits, but colored. Today I saw a melon, not yet netted, on a vine dying of bacterial wilt, turning color. One of my apple trees that's been very stressed in the drought, has pingpong ball sized fruits with seeds already turning dark. It's been such a stressed year, I think a lot of this is going on.

Sorry Olpea and Konrad. My plums are already dried and cooked. So I found the second photo on the internet. My plums did not have all of the brown on the flesh. They were and will be delicious! Thanks so much. I do have a few more that I will cut up this week and post pics. Thanks guys! It was very exciting to pick these first plums! The plum for purchase from Raintree is now called 'Sehome'. I do not know if that was the same Italian plum they offered three years ago. It might be a 'Fellenberg'. I'll check with Raintree.