Q: We bought
raspberry plants last year. They have
looked fine and gave us some raspberries
over the past couple of weeks, but the
stems are dying. The leaves just turned
yellow along the whole stem all at once.
What is going on?
A: Nothing beats having fresh
raspberries on your ice cream.
Raspberries and blackberries are
collectively known as brambles. Your
raspberries are going through a normal
life cycle. What color are your
raspberries?
Red raspberries have
suckers (canes) that come out of the
ground. The first year, the cane is
called the primocane. It starts growing
in the spring, and at its tip, it may
send out a cluster of flowers in mid to
late summer. These berries ripen in
summer into fall. During the next
spring, the same cane is called a
floricane. It sends out flower clusters
along its length in the spring and
produces fruit in early summer. When it
is done producing fruit for the second
time, the cane dies and needs to be
removed for better air circulation in
the raspberry hedge. Better air
circulation helps prevent mildew and
mold diseases from developing on the
fall fruit produced on the primocanes.
Red raspberry canes
are suckers that need to be managed as
some will come up from the roots several
feet away from the main plant. Some
people mow the whole raspberry hedge
down in the winter and only get fruit
from the primocanes that come up each
spring. This only works on varieties
that produce fruit on primocanes.
Black raspberries do
not sucker and are managed as a
crown-growing plant. Purple raspberries
also have crowns, but they send up
occasional suckers that need to be
removed. On these raspberries, it is
rare to have primocanes that flower.
Normally, fruit is produced only on the
second year of growth of that cane.
These floricanes will die after
producing fruit for the first time and
should be removed.
Blackberries that
grow short canes are called erect types,
longer canes are semi-erect, and really
long canes are called trailing types.
All brambles do better when kept within
bounds by a trellis, but that is
especially true of trailing types. The
primocanes of semi-erect and trailing
types should have the tip of the cane
cut off at the top of the trellis or at
3 feet to 4 feet high. This causes more
lateral branches to form during the
first summer, which means more flower
clusters the second summer on the
floricane.
Your raspberries have
floricanes that are finishing up and
need to be removed. At the same time,
you can tie new primocanes to the
trellis to keep them in bounds.
Since brambles
are easily bruised, picking your own
will help them last longer. They may
need to be picked several times a week
to keep the ripe ones from falling off
the plant. If necessary, rinse in cold
water only to remove dust, dirt and the
occasional ant. Store them in high
humidity and as cold as possible without
freezing. They are easy to freeze by
placing on wax paper and not touching in
the freezer. Once frozen, place them in
a storage container.
E-mail questions to Jeff Rugg,
University of Illinois Extension at
jrugg@illinois.edu. To find out more
about Jeff Rugg and read features by
other Creators Syndicate writers and
cartoonists, visit the Creators
Syndicate website at www.creators.com.
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