Raspberries
For Backyard Growers
Nicolas Tardiff
College of
Agriculture and
Natural Resources
Warning !!!
• The Internet is full of resources.
• Always double-check the information.
• Make sure the information is for your intended use.
Most of the information about raspberries is for
commercial growers.
• Be careful about myths and legends.
Table of Contents
• Raspberries 101
• Growing raspberries
• Running into problems
A thing or two useful to know.
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Rosales
Family: Rosaceae
Genus: Rubus
Mid- Atlantic native species
• Rubus occidentalis - Black raspberry
– Includes hybrid purple color
• Rubus strigosus - American red raspberry
– Includes hybrid yellow color
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Rubus odoratus – Flowering raspberry
Rubus laudatus – Plains blackberry
Rubus pensilvanicus - Pennsylvania blackberry
Rubus parviflorus - Thimbleberry
Rubus hispidus - Swamp dewberry
Rubus flagellaris – Northern dewberry
Noteworthy species
• Rubus idaeus - European red raspberry
• Rubus laciniatus - Evergreen blackberry
– Also known as cut-leaf blackberry
– European native
• Rubus ursinus - California blackberry
• R. ursinus × idaeus – Boysenberry
– Raspberry-blackberry. California native
• Rubus loganobaccus - Loganberry
– Raspberry-blackberry. California native
• Rubus spectabilis – Salmonberries
– Native from west coast US - can be yellow, red or purple
• Rubus chamaemorus – Cloudberry
– Also known as baked apple. Yellow fruit.
– Very cold climate in the eastern part of North America
• Rubus phoenicolasius - Wineberry
– On the invasive species list in Maryland.
Characteristics
Rubus occidentalis & Rubus strigosus
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Hardiness zones 3 to 9
Plant costs less than $15/ea and live for ~10 years
Like sun and wet light drained soil
Hand-pick or harvest mechanically
Nectar source for honeybees
Can be locally invasive
Can be very vigorous
Can be very productive
Not a berry but made up of droplets
Excellent source of antioxidants
Red and Yellow
Black and Purple
•Grow in hedgerows
•Grow in hills
•Propagation by the roots
•Propagation by the head
•Early to summer bearing
•Fall bearing (everbearing)
•Early to summer bearing
•Mid-June to frost
•Mid-June to mid-July
•Winter Greenhouse
•Orange color available
Bramble Home Production Recommendation
University of Maryland Extension
• June Bearing (June 15 – July 15)
– Black Varieties: Bristol, Haut, Jewel, Allen
– Purple Varieties : Royalty, Brandywine
– Red Varieties: Latham, Hilton, Titan, Lauren*,Taylor, Reveille,
Newburgh
• Fall Bearing: (July, August – Frost )
– Red Varieties: Autumn Bliss, Caroline*, Heritage, Josephine*
– Yellow Varieties: Fall Gold, Anne*
* Released from University of Maryland
Propagation
Black raspberry plant in container
2011
What to do with fresh raspberries
Half less to very low sugar jam
+
Summer 2009
=
Summer 2009
www.pomonapectin.com or at your favorite Health Food Stores
01/23/2010
- The American Pie Council® National Pie Day : January 23rd
- Pi (π) Day: March 14th (3/14 – get it?)
How do you tell the difference
between a black raspberry berry and a
blackberry berry?
Black raspberries
At harvest, the receptacle
remains on the raspberry
plant.
Blackberries
At harvest, the receptacle
remains in the blackberry
fruit.
Growing Raspberries 
Year to year name change for the
same cane:
• Primocane: 1st year cane
• Floricane: 2nd year cane
For June-bearing brambles: primocanes emerge as shoots
from the crown and grow into vegetative cans. They
overwinter and become floricanes, producing flowers and
fruits in year 2. Canes die and are pruned out.
Late summer/fall bearing brambles produce their fruit on
primocanes. Canes are usually cut to a 2-inch stub when
fruiting is over.
• Test your soil. Ph of 5.5 to 6.5 is optimal
• Need a soil with 50% organic matter
• Can be planted on raised bed to help with drainage
• Don’t need fertilizer just add organic matter (1”) in springtime.
• Use mulch and/or compost around plant to keep weed-free and soil moist.
• Inspect the plants for disease and injury periodically
• Need 1” of water a week. Water the roots, not the leaves
• Harvest time, can be very intensive.
– June bearing: the period can be 2 to 8 weeks
– Late summer/fall bearing: the period can be 8 to 12 weeks.
How to plant raspberries
Sunny and
windy site
Weeds
need to be
controlled
8-10 ft between rows
18 inches wide
3 feet wide
3 feet wide
Mid-June 2009
Black raspberry*: dig a hole of 18” wide and 18” deep
Red raspberry: dig a trench of 18” wide and 18” deep
Beginning of
May 2009
•You can buy a 2-3 year old plant or a bare root at your garden store.
•You will achieve quicker results with a plant.
•It will take 2 years for a plant to 3 years for a bare root to reach full production
•Both can be planted in ealy spring or end of summer
•Remove blossoms during the first years when planted in springtime to improve root
development.
•Do not cover with more than 2” of soil or compost.
Pruning and Training
depends on what you’re growing
Summer (June-bearing) Red
• Removing canes after fruiting ( summer ). Cuts should be made close to
the ground. Remove completely and throw away for prevent disease. If floricanes
retain their leaves and the cane diseases are minimal, it’s recommended to leave
the spent fruiting canes until dormant pruning ( winter ).
• Thinning shoots and canes (early spring )
Remove weak canes. Keep
large canes that are spaced about four to six inches apart as evenly as possible
over the width of the row. Confine row width to 12 to 18 inches. Generally, four
to six large-diameter canes per linear foot of row is optimal.
• Heading back shoots and canes ( early spring) Tall canes (more than
five feet) should be cut back. Head tall, vigorous canes four to eight inches about
the trellis wire but not more than ¼ of the height. When winter injury occurs, all
canes need to be cut below the point of winter injury.
Heading Back Shoots and Canes
Red late summer/fall bearing
(a.k.a. ever-bearing)
• Ever-bearing raspberries are usually grown for just the fall crop.
– Fruiting canes are removed and destroyed by mowing during wintertime after being killed
by the frost.
– Mowing: Cut to the height of 2 or 4 inches. Max 6”. One month after been killed.
– The next season a new flush of primocanes appears and bears fruit in the fall.
– Thinning is not usually necessary but weak and diseased canes should be removed. Keep
the row narrow too.
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If 2 crops are desired, then fall-bearing raspberries work like red raspberries.
– After fall harvest, prune and destroy the upper portion of the cane producing the fall crop.
– The next crop will be a summer harvest.
– Expect a small crop ( 10-25% of the fall one )
• A fall-only harvest can produce 89% more raspberries than a 2 crops
system and is less prone to disease. It’s more simple, too.
Black
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If the primocanes are allowed to grow unchecked, they get long and are very difficult to
manage without support of some kind. The fruits production will be reduced.
• Summer Heading (Tipping) Pinch off (head) the tips of new canes when the canes
have reached a certain height. This induces growth of side branches and results in plants
that are stocky and self-supporting and have a large amount of bearing wood. Tipping is
done by removing the top 2 to 3 inches of new shoots as they develop.
– Black raspberry shoots should be tipped when canes reach about 20 to 34 inches.
– Brandywine purple raspberries are usually tipped at about 36 inches.
– Royalty purple raspberries do not require heading.
• Head the tips of new growth to avoid cutting the tips later in the summer to prevent
disease and problems. You have until August to pinch the tips of the primocane.
• Removal of Canes After Fruiting ( summer ) by cutting close to the ground.
Black
• Thinning Canes ( late winter when dormant ) Remove
canes less than half an inch in diameter at the base in
the spring. Four to six strong canes per hill is
recommended. Cut close to the ground.
• Heading Back Laterals ( Late winter ) Head back laterals
in the early spring but before the buds swell and grow.
Keep 8 to 10 buds – about 8 to 10 inches long
• Heading Back Canes to their floricane height ( late
winter ) if you didn't do it during last summer.
20”-34”
Training and Trellising
Abiotic plant problems
Disease, Pest and Insect Control
Abiotic plant problems
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Water
– Too much and/or poor drainage in heavy soil.
» Drowning
» Opens door for virus
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Not enough water
» Stresses plants
» Plants can survive a serious dry period by losing their leaves but forget fruit for next year.
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Not enough sun and/or poor air circulation
» Plant grows poorly.; more susceptible to diseases
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Container too small
» Plant grows poorly. Ex: Hole in clay soil or in container for a black raspberry plant needs to be at
least 18” wide and 18” deep. Minimum is 12” for a well-drainedg soil.
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Too much fertilizer
» Causes a lot a problems. 1” to 1.5” of compost or organic matter a year is all they need.
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Soil pH
» pH should be between 5.5 and 6.5.
Birds
Brown Thrasher (Toxostoma rufum)
First things first
Summer 2009
Start to feed the birds early in the growing season.
Plant fruits that ripen earlier than your raspberries to divert birds’ interest
(e.g., red mulberry).
Install protection
Net over
one plant
Raspberry cane borer
Prune out the infested cane below
The borer
Japanese beetle
Like to feed not only on the leaves but
on the overripe raspberries you didn't
pick on the branch or on the ground.
Diseases
– Viral
– Bacterial
– Fungal
Viral diseases
•Vary according to the virus strain and the
type of raspberry infected.
•No raspberries are immune - black and
purple raspberries are damaged more
severely than red varieties
•The viruses are not soil borne nor seed
transmitted.
Prevention:
•Maintain strict aphid control at all times,
especially in late spring and early summer
when aphid populations are likely to be high.
Raspberry Leaf Curl
Commonly spread from plant to
plant by the feeding of a small
sluggish aphid
Raspberry Mosaic
Disease Complex
Widespread disease
•Best time to detect virus symptoms is during
cool, cloudy weather in the mid-to-late spring,
early summer, and again in the early-to-mid
fall. A day or two before removal, thoroughly
spray affected plants with an insecticide.
•Plant in a windy area
•Maintain the fruit planting until the yield of
fruit becomes unprofitable, then destroy it.
Bacterial Diseases
Fire Blight
Crown & Cane Gall
•Strain on raspberry will not infect
apple trees and vice versa; it’s not the
same strain.
•Infection is through cane or root
crown injuries.
•All raspberries are affected.
•Not all canes will show the
problem and some, next to
infected cane, will remain green.
•Good sanitation is the key.
•Remove and destroy them
infected plant.
•Can overwinter in infected canes.
•Remove and destroy infected canes
as soon as you see them.
Fungus diseases
Orange rust
•Affects both
species
•Orange rust
does not
normally kill
plants, but the
plant is
infected for
life
Late rust
•Causes serious
damage to susceptible
red raspberry varieties
•Leaves are covered
with fine, light-yellow,
powdery masses of
spores in mid-summer
•The spore masses can
appear on leaf petioles,
shoots, calyces (fruit
caps) and even on the
fruits
Botrytis fruit rot (gray mold)
Rotting of mature
or near-mature
fruits of
raspberries
Cane blight
•More common on black raspberries
•Black raspberry primocanes turn brown or
black; floricanes will die before harvest
•Infection occurs at almost any time during the
growing season. Look for purple and brown
color on a primocane.
•Overwinters; dead canes continue to remain a
source of infection for several years. Remove
and destroy all old fruit canes immediately
after harvest
•Top canes in a dry weather condition only,
without forecast of rain
•Use fungicide as preventive method if disease
was present the year before or is detected on
the field and lime-sulfur in early spring.
Spur blight
The V-shaped lesions are characteristic
•This disease is more common and
serious on red and purple raspberries.
•Chocolate brown, dark blue, or purplish
V-shaped spots appear just below the
leaf or bud, usually on the lower portion
of the stem
•Bark in the cankered area dries up, and
the canes may crack and split
lengthwise.
•Overwinters; remove and destroy all
old fruit canes immediately after harvest
Anthracnose
•Most common and
widespread disease of
brambles
•On red raspberries, it can
be common but is usually
not a serious problem as on
black and purple raspberries
•Remove badly diseased
canes.
Verticillium wilt
•One of the most serious diseases of raspberries more severe in black and purple.
•Cool-weather disease and is most severe in poorly
drained soils and following cold, wet springs.
•Black raspberry and blackberry canes may exhibit
a blue or purple streak from the soil line extending
varying heights.
•The fungus grows into the water-conducting tissue
(xylem) cutting the nutrients for the plant front the
bottom to the head. Overwinters in soil.
•Never plant a raspberry plant where potatoes,
peppers, eggplants, and tomatoes were planted
during the last 3 years.
Good cultural practices
• Maintain narrow row width or thin canes to open the plant canopy.
– Rows should not be more than two feet wide and should contain about 3-4 canes per
square foot for summer red or 3-5 canes by hill for black. Fall red raspberries, in
general don’t need thinning.
– This promotes air circulation and sunlight exposure for faster drying of canes, foliage,
and fruits.
• Avoid excessive fertilization
• Good sanitation is critical. Removing fruited cane after harvest is good practice. Fruited
canes should definitely be removed before new growth starts in the spring
• Inspect frequently and remove diseased plants. Early spring is also a good time to
inspect for virus diseases
• Minimize unnecessary physical damage to the plant. Use sharp pruning tools and
avoid pruning during periods when plants are wet or immediately before wet weather is
forecast.
• On ever-bearing varieties, mow (cut) fruited canes after been killed by frost.
Good cultural practices (cont.)
• Never plant black/purple raspberries less than 200 feet from a red raspberry
plant.
• Never plant raspberries where potatoes, eggplants, peppers and tomatoes
plants were planted during the last 3 years
• Plant away from wild brambles, rose and perennial weeds around.
• Plant in fertile, well-drained soil. No wet feet or lake at the feet of the plant.
• Use good IPM pest management methods
• Buy clean disease-free plants from a reputable source
Inspect the plant for disease and injury
periodically
Summer 2009
An insect or a fungus attacked the vascular system of the cane.
An earlier detection can save the cane and your production.
If you have a dead floricane at the end of June of beginning of July, the problem could
be from last year.
Resources
• Grow It! Eat It!
http://www.extension.umd.edu/growit
– We have all types of practical food gardening tips and
information. Check out our popular blog!
• Home and Garden Information Center
http://www.extension.umd.edu/hgic
– Here you will find factsheets, photos, and videos. You
can also subscribe to the free monthly e-newsletter.
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• Maryland Master Gardener Program
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– Consider becoming a trained MG volunteer!
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