I’m new to growing fruit and have recently become obsessed with growing thornless blackberries. I recently found this forum and have been reading everything on blackberries - glad to find people who love growing them like I do now!
I’m in Reno, NV, which is zone 7b, but we get late winter frosts until the end of May (today there is snow/hail and temps dipping to 28-29 several nights this week).
I really like having a long harvest season throughout the summer, so I have a few of the early fruiting types (Natchez, Ouachita, Arapaho, and 2 primocanes - PAF and Stark Black Gem) as well as some late ones (Chester, Triple Crown).
I’m worried about the late Spring freezes here. I read that the blossoms are generally safe above 27F. Are there any ways to help protect them when the temp does get below 27F while they’re in bloom? Are they less sensitive to damage when the buds aren’t open yet? (Mine haven’t opened yet - see photo with hail on the budding canes).
Thanks for any advice - only been growing these for a few years and have a lot to learn, but I’m very excited to learn how to be successful with thornless blackberries!
There’s not much to do, unfortunately. You can run sprinklers all night to keep water on the plants to prevent freezing, but in Reno that might be cost prohibitive.
I have had Chester thornless for over a decade in northern Utah (5b). Our last frost date is May 10 on average. Except for the year we hit 23 F on May 21, I’ve never had a problem with the weather taking out any of my blackberries (or peaches, nectarines or apples for that matter). I only get apricots every 3rd year or so though…
About the easiest thing to grow - no pests, deer don’t eat them, no spraying required, etc. Tip root them for endless expansion or gifts to friends. I don’t even trellis them and we swim in blackberries every year. Just prune in spring and that’s it.
The critters chew all the bark off my blackberry canes every winter, and they have wicked thorns. I assume it is deer, as it seems to extend too high for rabbits, or it could be both.
Yeah - water bills get expensive quickly here in the desert. I’ll see how they do this year - if I consistently lose the early ones, I may have to transition over to later varieties.
Yeah - we’re similar here. Apricots are hit or miss, no peaches about every 3rd year, but pears and apples have been fine.
We don’t have much of a deer problem (more of a bear problem) and we don’t have many bugs here like out East (except for coddling moths for my apples and pears). I don’t know if SWD is in this area or not - I never heard of SWD until I started reading posts on this forum. It’s also very dry here, so I’m hoping that keeps the mold to a minimum as well.
So far blackberries have been the most successful berry for me in Reno - blueberries have failed, raspberries are actually doing well, though.
I just put up a simple trellis this year since it’s very windy here and some of the heavier canes do get blown over.
Thanks for the help!
We don’t have many deer here and we have a high fence. We do have rabbits and ground squirrels that eat everything in my vegetable garden that isn’t protected, but they haven’t touched my blackberries so far. 
Bad news - looks like most (if not all) of my early fruiting blackberries that had buds during last week’s freeze (28 degrees 3 nights in a row) are dead. My PAF floricanes, Ouachita, and Arapaho all have dead buds on them (I snipped a few from each plant to check). Hoping that some buds that have come on since the freeze will still fruit. Glad I have Chester and Triple Crown to count on (hoping it’s not too hot of a summer - usually doesn’t get to 100 until early August, but it reached 85 already today, so who knows).