Re: Is there a need to winter bananas in 9b?
Steve, If you have any fruit, definitely protect and cover them (or remove them if they are close enough to harvest), as they will suffer and the flesh will crystallize if it gets even close to freezing.
As far as the plants, I'd say it depends on how established they are and each cultivar's particular hardiness. I live in Z10, but my family lives in Z9b in Riverside, and several years ago, I planted them (in the spring) and they've never been dug up. The minimum temps it gets out there is about 25, which is only for a few hours at a time. I am not sure how long your temp stays that cold, but I'd imagine in the bay area, there are a lot of microclimates, as I have friends who live in both Fremont and San Leandro, and while my friend who lives in San Leandro never gets a frost, my friend in Fremont gets hail and on the rare occasion, snow that sticks.
Look into what the cultivars you have can tolerate. For instance, here in z10, I even have a little trouble with leaf burn in January with a couple of the cv's, yet others look great!
For winter hardiness, I can say the best ones that have handled their quick dips down to 25 degree weather are:
Orinoco (both Dwf and Std), Manzano, Rajapuri, and Cardaba. Ice Cream did pretty good too, but suffered the most dieback, however rebounded the quickest.
What you can expect from an established stand would probably be about a 25-50% dieback on the harshest of winters, yet putting up with it for a year or two will give your establishing more strength for future years. By putting down a clear drapecloth over them when there's a chance of frost, you will retain a higher temp from the ground warmth, since our ground temps don't really get below freezing like the midwest. That's what is most damaging to musa.
Unless your plants are still very small and haven't had any pups emerge yet, I think you should just leave them in the ground and deal with one winter. Just dig them if we have a storm of the century that puts a freakish blanket of snow over California, which would likely not happen, but this has been a weird weather year. Good luck!!
__________________
you will never have enough bananas ^_^
|