How cold? Is this a standard measurement?

Hours, is that days, nights, total? I want some Mysore black raspberries, but the nursery says 100 hours chilling. (To me, chill is below 75 degrees!!! no joke. I live in zone 16)

Four days in the refrigerator--- will that do? or fifty nights at ?? temps, for two hours each night?

???

Chilling requirements vary by plant. Some need to freeze the tops, others like perennials we have here in FL go dormant as soon as the nights dip below 55. It has to be cold enough to send a growing plant into dormancy (gradually over a week or two, not suddenly like shoving them in the fridge) and keep it there for a month or two. Probably down into the 40's at night and no higher than 55 or 60 during the day. I don't think 4 days in the fridge is going to cut it as 100 hours of chilling.

Hm, where you live, it's a puzzle! Perhaps a big planter on wheels that you could move from the sun to the shade for winter, then water it daily with ice cubes to cool the soil, and maybe insulate around the planter and put a cooler upside down over the top to give the plants a dormant period. Once you've kept it cold for a month or two (however long you have patience for) you'd gradually move it back out to the sun, and when the plants start growing again, water and fertilize.

If you can source the plants now, they will have been dormant. You could grow them over this summer, you might get one crop of berries this year if the plants get big enough in one (long!) season. Then next winter you could worry about getting them to go dormant or just let them do their thing.

It sounds like a lot of work to me. I'd look for somebody who will just import the fruit for you, myself.

I have read of a tulip gardener in Southern California who puts his tulips bulbs inside the refrigerator for several weeks, to achieve the chilling requirement. So if you got a spare refrigerator, maybe you can do similarly. Oh I found the article:
http://www.cbsnews.com/news/a-...

Another website gave "Rubus niveus" these alternate names:

Hill Raspberry,
Mysore Raspberry, < - - -
Black Raspberry,
Indian Raspberry

Searching the ATP Plant database for "Rubus niveus" gave five hits:

Hill Raspberry (Rubus niveus) < - - - -
(Rubus niveus var. furfuraceus)
(Rubus niveus var. pauciflorus)
(Rubus niveus var. sericeus)
(Rubus niveus subsp. leucocarpus)

Assuming "Hill Raspberry" is the one you want, another synonym might be "Ceylon Raspberry".
Hill Raspberry (Rubus niveus)

However, I see no photos and no descriptions of any of those varieties in our database!

Usually I would suggest saving a lot of effort and finding some variety you CAN grow in Zone 16. The other website database (pay-for-view) gives "Zone 11" as the hottest limit where they are likely to grow.

If you decide to try anyway, "Zone 11" makes it sound like they need to get down to 5C (40F) or lower.

Do they grow fast enough that you could take cuttings once each year, root them in pots, move the pots to a lighted cold room, then plant them and get a crop from the first-year growth?

Elaine might be right, that they need gradually falling temps to convince them to go into dormancy before the big chill. I don't know.

Do you travel to colder climates often? Maybe transport rooted cuttings back and forth to the mainland - chill them elsewhere

You might ask first, about transporting species considered invasive in some places where they do thrive.

Or, if importing them to St. Croix IS legal, maybe get a mainland friend to ship you pre-chilled cuttings yearly.

It sounds to me like you might be taking on a lot of work. Are these really that much better than other raspberries?

On the other hand, if you succeed, you will have major, MAJOR bragging rights!

The other two places I can think of asking the same question (How to give Mysore Black Raspberries as much cold dormancy as they need) would be the Florida forum, and 'Edibles'

http://garden.org/forums/view/...
http://garden.org/forums/view/...

Maybe, perversely, someone in the "Tropicals" forum would have an idea:
http://garden.org/forums/view/...

Vines and Climbers?
http://garden.org/forums/view/...

When I "searched all forums" for "rubus", I got 9 threads where someone mentioned it. If you try that and then search each of those threads for the word, you might find some fans of the genus, and ask them if they know. One way to "ping" someone in a context is to post to a thread, perhaps this thread, or the thread where you found their name), their exact screen name preceded by an "@" sign like so: @coconut.

Oh, my, Rick! Thank you for such a long answer!

I dearly love black raspberries, and have not tasted one in well more than twenty years! Our coldest nights are about 68 degrees with day time temps in the low eighties. Many plants cannot take the long 'hot' nights, they don't get to rest. Tomatoes can be grown for about three months, in the winter. But then our boiling hottest summer days are around 95, with 85 degree nights.

I guess I will wait until my friend's newly imported plants, (absolutely tiny!!) do what they're going to do, well or badly. If I can find a wealthy codger to fund me, I'll build a refrigerated greenhouse! hahahahahaha!

Cheers,

Melissa

>> If I can find a wealthy codger to fund me, I'll build a refrigerated greenhouse! hahahahahaha!

That went through my mind, but I bit my tongue and shrank it down to "a few cutting in a cold room".

But they would be very big when you put them outside.

Mostly I hear about people "pushing their Zone" by wrapping plastic and blankets around heavily-mulched things to get them through a cold winter. That's easier than air-conditioning a greenhouse!

Of all the blackberries, that one has the shortest chill requirement (I think).
That type is grown in Puerto Rico and Hawaii (and I forget where else); do we have members in those locations who can chime in?
How much different is your climate than those two places?

A spare refrigerator just might work.

Puerto Rico and Hawaii are large, and have very high mountains that do get quite chilly. Here, my island is so small (7 miles at the widest, by 28) that the warm sea keeps the nights well above 65 degrees. No chill there! But we are at similar latitudes.

All the zone stuff is about coldness, and how far north, and blah blah. I have yet to read about subtropical and tropical requirements. Even Logee's. Although I do have a book about Florida fruiting plants, and it has some that do well in different parts of that huge state.

I'm not quite wealthy enough to have a refrigerator just for some plants to live in for two months out of a year, booo. And I haven't been Up North in many years. I realized that I was not happy visiting there...

A friend relaxing with a novel at my beach hang out, two miles from my house

Melissa, that looks absolutely lovely, although I'd be either diving for a shade tree within minutes or else sitting directly in the water! Some folks tolerate heat much better than others. I haven't quite mastered it (but still trying!).

Ohh, it's hard to feel sorry for you, Melissa! I live a mile from a nice beach, too, and my family are very unsympathetic when I say it's "cold" here in Florida. "Too cold for the beach, Mom?"

What about finding a large insulated cooler (you know, like what you take to the beach with drinks in it, only BIG). They make big ones for people who go fishing etc. If you could freeze something like milk or juice cartons with water in them on a regular basis, you might be able to keep the plants in a cooler cool enough (but not freezing) for a couple of months.

Here's another caveat to growing berries where you are - and I found this whilst trying to grow strawberries in my back yard. (I have no idea how the commercial growers do it, and I don't think I want to know, either) I got about one strawberry for every 10 that the birds, squirrels, bugs, slugs and raccoons got. If the local parrot population had found my garden, I'm sure I would not have seen a single berry.

So you run the risk of growing these wonderful raspberry plants, then having to fence, screen, and otherwise guard them until they're ready to pick. Or growing the much-missed delicacy and tasting one or two berries before the local wildlife developed the taste for them. Don't want to discourage you, but . . . it's a lot of trouble when you might just be able to import the fruit. Even if it costs you an arm and a leg to treat yourself once a year, it will be less than buying plants and going to all that fuss.

Deb, I think it's in the bones. My mother was always too warm, and my father was always chilled. I'm the chilled one!

I've never seen wild black raspberries for sale, have you? Sometimes there are the vapid red ones, $7 for a tiny carton, five ounces? And probably loaded with pesticides. I'll be moving to a new home even closer to the beach in a year, rich soil! And I'll build screened houses for my food. I know all about hungry critters, they destroy all my mangoes every year, the birds and fruit bats. Never see them when the mangoes aren't ripening.

I saw a set up where someone hung rain gutters at head height, and had strawberries hanging out of them, might ty that.

I still don't have a comprehension of what "100 hours of chilling" means.

Is this any help? In Cornell, they use the greenhouse for warmth, not coolth.
But part of it talks about moving canes around in pots and then getting a quickie crop from them.

http://www.hort.cornell.edu/gr...

"Floricane raspberry production
The concept of floricane production is to grow plants in pots, allow plants to fulfill their chilling requirement, then bring them into a greenhouse where the plants experience “spring.” "
...
"If a cooler is available, canes can be held inside for several months, then moved into the greenhouse for late spring production"


However, it sounds like primocane-fruiting raspberry varieties (Rubus idaeus L.) have easier chilling requirements.
http://hortsci.ashspublication...

This link is in plain English; should be fairly easy to understand.
Basically, where you live - you would need a refrigerator to grow the blackberries you desire.

http://www.raintreenursery.com...

Ah, that's interesting! Thanks! Maybe it's mostly air temperatures, the soil needn't freeze?

Black Raspberries.

Oh Melissa, you are indeed daunting. When I get a hankering for black raspberries (I don't much like the red ones) I buy a big bag of them frozen. Really, they are pretty darn close to fresh and mostly I make something with them like cobblers or smoothies or just pour them over ice cream. They are sold in all the upscale supermarkets here, all kinds of alien berries like blueberries, cherries, etc.

Really??! I'll have to go look. Last time, all I saw frozen were blueberries and strawberries. I didn't bother with the strawberries. Hum, thanks for the heads-up!