of Rhode Island GreenShare Factsheets
and blackberries are the group of cultivated fruit crops referred
to as brambles. Raspberries and blackberries are distinguished in
the following way: when picked, the white receptable (core) comes
off with the blackberry fruit, whereas it remains attached to the
Many cultivars of raspberries and blackberries are available to
the home grower. It is important to choose cultivars which can withstand
the winter temperatures in your area. Also consider productivity,
use, season of ripening and quality as well. The thornless blackberries
are of marginal hardiness in the Northeast and should be planted
only in a protected area. In addition, they are susceptible to rodent
red raspberries: Reveille, Killarney, Canby*, Festival*, Newburgh
Summer-bearing yellow raspberries: Amber
Fall-bearing red raspberries: August Red, Ruby, Heritage
Fall-bearing yellow raspberries: Kiwigold, Fallgold, Goldie
Summer-bearing black raspberries: Allen, Bristol, Alleghany,
Summer-bearing purple raspberries: Brandywine, Royalty
* = nearly thornless
Blackberries (Thornless): Black Satin, Thornfree, Chester,
Blackberries (Thorny)*: Darrow, Illini, Shawnee
* = Resource: Bramble Production Guide, NRAES-35
Selection and Soil:
Brambles grow best on a sunny site in sandy loam soil. Although
brambles tolerate a broad range of soil types, they require soil
with good drainage. A common cause of death in brambles is the
Phytophthora root rot, which tends to infect plants predisposed
by "wet feet" - meaning there is standing water in the subsoil.
In addition, excessive water, either on the soil surface or below,
can be troublesome during winter when alternate freezing and thawing
of surplus moisture in flat ground causes considerable damage from
heaving. For this reason do not plant raspberries in sites where
water accumulates after a rainfall or where the water table is
4 feet of the soil surface. If this is not possible, plant raspberries
on a raised bed at least 10 inches in height. Selecting a site
higher than nearby land improves drainage and reduces the danger
of cold injury and late spring frosts.
the planting free of disease is most important for successful growth.
Because the principal source of disease is wild brambles, choose
a site far from woodlots and old fields and, if possible, destroy
all wild brambles growing within 500 feet of your site.
previously cultivated site is best, but only if crops susceptible
to the disease Verticillium wilt - raspberries, strawberries, tomatoes,
potatoes, peppers or eggplants - have not grown there before. If
you choose a new site, till the sod under and plan a cover crop
one year before planting.
moisture during the growing season is essential for good cane growth
and fruit production, particularly during periods of drought. For
ease of irrigation during the growing season, locate the planting
near a water source.
Set plants at least 30 inches apart within rows, 9 to 10 feet between
rows, and 1 inch deeper than grown in the nursery. Plant rooted
canes early in spring, and set tissue culture plantlets after danger
of frost has passed. Remove old canes which may be attached to the
new plant, because they are a source of disease. Place a ridge of
soil along each row one month after planting. Do not fertilize for
several weeks after planting, and water liberally because brambles
have shallow root systems.
Brambles are easily injured by too much fertilizer. Apply no more
than 5 pounds of 10-10-10 per 100 linear feet of row the first year
and no more than 10 pounds in subsequent years. Apply fertilizer
only in the early spring before flowering. Avoid using fertilizers
which contain chlorides. For best performance, have a leaf analysis
and soil test done every two to three years and follow subsequent
will likely be required between bloom and harvest. When necessary,
irrigate early in the day after plants have dried from morning dew.
Plants which remain wet during warm nights are more susceptible
irrigation is particularly suited to small fruit crops and is an
effective and efficient way of using available water. Drip tubes,
tricklers or emitters drip water continuously or intermittently
into the root zone around the plant so that the plant receives as
much water as it can use but no more. Inter-row spaces remain firm
and dry, and the root zone remains moist at all times. Very little
water is lost from evaporation, wind drift or too deep penetration.
Cultivate the area between rows from early spring to mid-July to
control weeds and eliminate suckers. To avoid injuring roots, cultivate
no deeper than 2 inches. A grass strip can eventually be established
between rows. Grass seed germinates best if seeded in September.
has a major effect on the production of quality fruit. The systems
used affect growth rate, fruit number, size, sweetness and susceptibility
Primocane Fruiting Raspberries: This type of raspberry plant
produces fruit at the top of first year canes in late summer and
on the lower portion of these same canes in early summer of the
second year. Most growers choose to sacrifice the early summer crop
in favor of a smaller but higher-quality late summer crop, because
pruning is then easier and fruit quality is higher. When pruning
primocane fruiting raspberry plants for a single late season crop,
cut canes to the ground in early spring. Primocanes grow and fruit
in late summer of the same year. It is important to cut old canes
as close to the ground as possible so buds break from below the
Fruiting Raspberries and Blackberries: Floricane fruiting types
produce buds on second year canes. Unlike primocane fruiting types,
canes must remain intact throughout the winter and until the completion
of harvest the second year. During second year flowering and fruiting,
new canes are growing. These primocanes can interfere with spraying
and harvesting, shade leaves and laterals of fruiting canes, and
compete with floricanes for water because each shares a single root
system. It is important to minimize this interference by proper
pruning and trellising.
traditional method of management is to permit primocanes to grow
through the season and fruit the next year, then cut them at ground
level after fruiting. In early spring, the remaining canes are topped
to a reasonable height and thinned to a desired number. Diseased
or winter-damaged wood is removed.
way to reduce plant interference and competition is to mow half
of the planting alternately each year during the dormant season.
During the spring after mowing, primocanes emerge and grow without
interference from fruiting canes. The following year, the floricanes
flower and fruit and are then cut to the ground. Advantages of this
system are that cane thinning and pruning are not necessary and
spray material costs are reduced. Disadvantages include a reduction
in fruit quality, berry size and yield.
third alternative is to remove all but 4 or 5 primocanes per linear
foot of row in June. With this system, primocanes are selected that
will be carried into the following year for fruiting. Primocanes
that are not selected are cut when they reach about 8 inches. Advantages
of this system are that those primocanes not selected are removed
when they are small and succulent rather than when they are large
and thorny, and fruit size and production of the current season's
crop are increased.
Many growers of primocane fruiting raspberries have found that a
temporary trellis is necessary during the fall harvest season. One
system that works well consists of T-shaped wooden or metal posts
approximately 7 feet long with 3-foot crossarms. The end of each
crossarm contains a screw eye or other device that holds a length
of bailing twine, which is cheap and disposable yet strong enough
to hold canes erect temporarily. Holes are dug 25 to 30 feet apart
in the center of each row; they are 3 feet deep and slightly wider
than the diameter of the bases of the posts. Immediately after the
holes are dug, a 3-foot section of plastic pipe is set into each
hole to maintain integrity. Near the time of harvest, the T-posts
are inserted into the plastic-lined holes. After harvest, the twine
is cut and the posts are removed and stored for another year. Because
the plastic pipes are buried, they do not interfere with cane-cutting
of floricane fruiting raspberry and blackberry plants helps reduce
primocane interference and improves production. Without trellising,
fruiting canes must be cut short in the dormant season to prevent
canes from breaking or tipping over. Because most of the fruit buds
are on the top half of the cane, topping low can significantly reduce
the productivity of a planting.
brambles in a hill is a trellis system that is occasionally used.
Advantages are low cost, ease of harvest and suitability for two-way
cultivation. The disadvantage is low yields per unit area.
to a single wire 3 or 4 feet above the ground prevents cane breakage
but allows only a small amount of light to reach the lower portions
of canes and forces primocane growth toward the aisles; this growth
can interfere significantly with spraying and harvesting.
interference can be reduced and yields increased by using a trellis
that separates the fruiting canes from vegetative canes. One such
system is the V-trellis. This trellis can be constructed with two
sets of opposing posts; each placed into the ground at a 20 to 30-degree
angle. Fruiting canes are tied to wires on the outside of the V
in early spring; and primocanes are permitted to grow in the middle
of the V. Spraying, harvesting and pruning are easier because floricanes
are pulled to the outside where they are accessible and primocane
interference is minimal. Thepresence of primocanes in the middle
forces lateral growth outward. Yields of several raspberry cultivars
have been increased using a V-trellis, primarily because the amount
of light reaching the plant canopy is increased.
A similar system can be constructed using two T-posts. Generally,
the T-post requires an additional crossarm between the ground and
upper arm to support the fruiting canes. The disadvantage of theT-trellis
is that adjustments to accommodate annual variations in cane height
are difficult to make. Although cane heights are estimated before
constructing any trellis system, theV-trellis allows adjustments
of the wire heights to be made at any time.
trellis posts and anchors from readily available materials. Monofilament
plastic wire, now the material of choice for trellis systems, is
as strong as wire but much lighter and easier to handle. Inexpensive
devices are available to hold the monofilment taut at the anchoring
post and to rejoin lines that have accidentally been cut. When designing
a trellis and choosing materials, keep in mind the potential 15-year
life of the planting.
Different types of brambles require specific pruning treatments.
Red Raspberries: Prune off winter-damaged tips in mid-March.
Top canes as high as the trellis permits but below the point of
winter injury. Tie canes loosely to the trellis wire to prevent
wind damage. Leave 3 or 4 canes per linear foot of row when thinning
Raspberries: Remove at least 4 inches of tip from primocanes
when black raspberries reach a height of 24 inches. By the end of
the season, primocanes will be branched with long laterals; these
should be supported by trellis wires in winter to prevent breakage
from snow. Shorten laterals in early spring to remove any winter-damaged
wood and to maintain berry size. Leave 2 to 3 canes per linear foot
of row when thinning out canes.
Raspberries: Vertical growth of purple raspberries is substantial.
Primocane pinching will reduce cane height, but cane diseases may
invade the wound left by pinching. To thin, leave 3 fruiting canes
per linear foot of row.
Thorny Blackberries: Tip primocanes when they reach a height
of 3 to 4 feet to stiffen canes and induce lateral branching. Shorten
lateral branches to 12 to 16 inches in early spring, and thin canes
to 2 per linear foot of row. Alternate-year mowing helps avoid the
difficult task of pruning.
Blackberries: Shorten fruiting canes to the top trellis wire
in early spring or weave around the wire. Shorten laterals to about
18 inches. Low-growing laterals are more easily protected during
winter than upright canes. For good production maintain 6 to 8 canes
do not keep well on the plant and must be harvested every 2 or 3
days. Expect a small crop the first year after planting. Everbearing
reds may produce a small crop in fall of the planting year. Production
reaches its peak the third year after planting and slowly declines
in subsequent years. Many growers choose to replant a site after
To store raspberries for later use, proper post-harvest care is
critical. Select only berries in good condition and immediately
cool them to as close to 33 degrees F as possible. Wrap in plastic;
allow them to come to room temperature before removing the plastic
wrap to make sure condensation forms on the wrap, not on the berries.
for this fact sheet was taken from: The
Home Fruit Planting, Information Bulletin 156,
A Cornell Cooperative Extension Publication, by Marcia Eames-Sheavly
and Marvin P. Pritts, 6/95.
are poisonous! Read and follow all safety precautions on labels.
Handle carefully and store in original containers out of reach
of children, pets or livestock. Dispose of empty containers
immediately, in a safe manner and place. Pesticides should never
be stored with foods or in areas where people eat.
When trade names are used for identification, no product endorsement
is implied, nor is discrimination intended against similar materials.
Be sure that the pesticide you intend to use is registered for
the state of use.
The user of this information assumes all risk for personal injury
or property damage.
information, call the URI CE Gardening and Food Safety Hotline
at 1-800-448-1011 or (401)874-2929 from outside Rhode Island;
Monday-Thursday between 9 am and 2 pm.
of Rhode Island Cooperative Extension provides equal program