http://www.meiosis.co.uk/fruit/karaka_black.htm I found this while searching . I could not find a zone rating . However I found a Canadian selling seeds from this on eBay . He claims zone 4 . Meiosis site claims 10 to 11 grams for the fruit . Wondering when the USA will get to try them .
eBay blackberry seeds unlikely to have been isolated during pollination of the fruit; the resulting plants could vary considerably from Karaka.
I agree . I only mentioned it because he stated zone 4 . I will wait for it to become available . Lots of zone 4 and 5 growers would be interested in trying it .
The site makes 2 references to “cool climate”, which is promising