North American Fruit Explorers mailing list at ibiblio

[Jim Fruth <jfruth@uslink.net>]

Re:

With regard to blackberry cold tolerance, I would like to hear more about
what northern gardeners are experiencing as they attempt to grow
blackberries beyond zone 6.

Michele Stanton

    I tried most of the catalog varieties of blackberries and, of those that
would survive zone 3 winters (with or without winter protection), the
berries were still green when the first freezes occurred. I said "most"
because I hadn't learned about Doyle's Thornless Blackberry until three
years ago - I tried all the others that were advertised in the multitude of
catalogs that flood my mailbox.  I did not try Doyle's because of negative
comments about it that I received from former zone 3 growers of that plant.
    Then, two seasons ago, I learned of an Indiana Company that advertised a
plant identical(?) to Doyle's claiming that it would survive in zone 3.  So
I decided to try it.  My order consisted of tissue culture plants and it
arrived sans packaging; I received a box of mud balls - I have one surviving
plant and I'll learn if it survived my winter next Spring.
    As for blackberries in general, they all came from the wild, at one time
or another, so I've been experimenting with wild types.  Britton & Brown
lists sixteen separate species in the Eastern United States and I set out to
find all that grow in my geographical area.  When examining wild types, we
must understand that many/most wild plants live on the brink of extinction.
They are crowded by other plants.  They compete for what few nutrients that
may be available.  Taller plants rob their light and they must depend on
Mother Nature for what rain-drops they get that their competitors don't
grab.  We cannot judge a wild plant in the environment in which it grows; we
must bring it home and nurture it like any other treasured garden plant.
    Some of those wild types weren't worth growing.  Some have few, but
tasty, fruit.  They don't produce enough to warrant garden space.  Some
produced betterunder the stresses of the wild.  Some produced copious
amounts of fruit so soft when ripe that they became mush when harvested.  My
trials are nearly over and it looks like I'll be growing two varieties.  One
of those is worthless in even a half-day's sun, preferring regular but scant
light.  It isn't a great producer but it thrives under low light conditions
where little else will.  The other is (obviously?) one of the parents of
Doyle's blackberry because it produces copious amounts of fruits though
smaller that those of Doyle's claims.  It can produce fifty or more berries
on a short branch; it didn't produce like that in the wild.  And, best of
all, it needs no winter protection.  I'll need another year's evaluation
before I make any further claims about it.
    Before I embarked on my blackberry trials I begged nursery people to
sell me wild plants that grow in their area - for whatever reason(s), all
refused.  In one instance at least, that is about to change.  A NAFEX member
and I negotiated a trade.................five of my Boysenberry plants for
five of her Bangor Maine Blackberry plants, fair enough.  Now I shall have a
new plant to play with.  Word of my successes with growing blackberries in
zone 3 has gotten out and, every year, folks knock on my door asking to buy
wild plants.  I oblige.
-- 

Jim Fruth
Brambleberry Farm
Pequot Lakes, MN
www.bberryfarm.com
Jams, Jellies and Syrups