Growing Grapes in Maine

• Growing Grapes in Maine (PowerPoint Presentation)

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David T. Handley, Vegetable & Small Fruit Specialist, University of Maine Cooperative Extension
January 2013

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Table of Contents

• Grape Expectations
• The Grape Plant
• Grape Growth
• Grape Varieties
• Hardy Grape Varieties
• Hybrid Types
• Site Selection
• Site Preparation
• Planting Grapes
• Establishing the Vineyard
• Trellising Grapes
• Irrigation
• Training Grapes
• Growing Grapes
• Pruning Grapes
• Fertilizing Grapes
• Harvesting Grapes
• Grape Problems
• Maine Grapes: Bottom Line
• Grape Resources

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Grape Expectations

What are your goals?

• Personal
• Financial
  • Grapes = high-risk crop
  • Invest wisely
  • Or not at all
• Scale
  • Home Garden/Hobby
  • Commercial
• Table Grapes
  • Market?
    • Quality, quantity, competition
• Wine Grapes
  • Variety very limited
  • Quality/quantity of product
  • Market?

Potential (likely) Problems

• Winter injury
  • Buds, Cane, Trunk
• Short growing season
  • need early maturity
• Pest Problems
  • Diseases, insects
• Markets

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The Grape Plant

Perennial Vines

• Long-lived (?) trunk
• Fruit on 1 yr. old canes
  • Lubrusca types: buds 3-5
  • Vinifera types: buds 1-3
• Self-layering (rooting)
• Self-fertile (mostly)
• Long growing season (160+ days)
• Winter-tender

Trunk

• Long-lived (?), perennial
• 1’-7’ tall, depending on the training system
• Winter hardy to -10º to -40º

Cordon

• Permanent branch, perpendicular to the trunk
• Supports fruiting (1 yr old) canes
• Improves exposure, eases harvest

Cane

• One-year-old vine growth
• Supports buds, fruiting shoots
• Health of cane determines the quality of the crop
  • Most productive: moderate vigor
  • 3/8” thick
  • Chocolate brown color
• Internodes: space between buds

Shoots

• Current year’s growth (green)
• Support fruit at nodes
• Will be canes next year

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Grape Growth

Shoot Growth

• Buds form at nodes
  • At leaf base
• Next years shoots (dormant)
• May produce laterals
• Fruit clusters
• 1-2 cluster/shoot
  • Remove excess clusters
  • Furthest from base
  • Better fruit size, ripening

Vine Growth

Vines can grow 15’+/year! Make sure they have adequate space and light.

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Grape Varieties

What should you look for?

• Hardiness
• Early maturity
• Hardiness
• Table vs. wine quality
• Hardiness
• Disease resistance
  • Hardiness

Lubrusca Types
(Vitus labrusca)

• Native, hardy
• Sweet, strong “foxy” flavor
  • e.g. “Concord”
• Blue/black, red, white
  • Some seedless
• Mostly table quality
• Limited wine utility

Vinifera Types
(Vitus vinifera)

• European orgin
• Not hardy
• No “foxy” flavor, less sweet
  • e.g. “Chardonnay”, “Cabernet”
• Blue/black, red, white
• Limited table utility

Hybrid Types
(labrusca x vinifera [x ripera])

• Interspecific crosses
• Improved hardiness over vinifera
• Improved wine quality over labrusca
• Active northern breeding programs
• Improved potential for NE wines

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Hardy Grape Varieties

Concord (Lubrusca) Types

(Click on thumbnails to view enlargements.)

Blue/Black: Table and Juice

• Beta
• King of the North
• Valiant
• Bluebell
• Fredonia
• Worden

Beta, King of the North

• Very hardy
• Early maturity
• Small, blue/black fruit
• Seeded
• Juice, jelly, table

Valiant

• Very hardy (ripera cross)
• Early maturity
• Small, blue/black fruit
• Seeded
• Juice, jelly, table
• Flavor only fair

Bluebell

• Very hardy
• Early-mid maturity
• Medium, blue/black fruit
• Seeded
• Juice, jelly, table
• Good flavor
• Disease resistant

Fredonia

• Hardy
• Mid-late maturity
• Med-large blue/black
• Seeded
• Juice, jelly, table, wine?
• Good flavor (Concord)

Candice

• Hardy?
• Early-mid maturity
• Small-med red/pink fruit
• Seedless
• Table, juice
• Good flavor; v. sweet

Reliance

• Hardy?
• Early-mid maturity
• Med. red/pink fruit
• Seedless
• Table, juice, wine?
• Good flavor

Vanessa

• Hardy?
• Early-mid maturity
• Med. red fruit
• Seedless
• Table, juice, wine
• Good flavor, texture

Somerset

• Hardy
• Early-mid maturity
• Med. red fruit
• Seedless
• Table, juice, wine
• Good flavor, texture
• Disease resistant

Edelweiss

• Hardy
• Early-mid maturity
• Med. white fruit
• Seeded
• Table, juice, wine
• Good flavor, texture
• Disease resistant

Hybrid Types

(Click on thumbnails to view enlargements.)

Frontenac, +Gris, +Blanc

• Very Hardy
• Mid-late maturity
• Small, blue/black fruit
  • Amber (Gris)
  • White (Blanc)
• Wine
• Disease resistant

Marechal Foch

• Very Hardy
• Early-mid maturity
• Small, blue/black fruit
• Wine (blending)
• Disease resistant

St. Croix

• Very Hardy
• Early-mid maturity
• Small, blue/red fruit
• Wine, table
• Disease resistant

Sabrevois

• Very Hardy
• Early-mid maturity
• Small, blue/red fruit
• Wine
• Disease resistant

Marquette

• Very Hardy
• Early-mid maturity
• Small, blue/red fruit
• Wine
• Disease resistant

Kay Gray

• Very Hardy
• Early-mid maturity
• Med-Large, white fruit
• Wine
• Disease resistant

Prairie Star

• Very Hardy
• Early-mid maturity
• Medium, white fruit
• Wine
• Disease resistant

St. Pepin

• Hardy
• Early-mid maturity
• Medium, white fruit
• Wine (sweet)

DIY Grape Variety Trials

• Test them yourself!
• Talk to other growers
• Always trial new varieties in small plantings (reduce risk)
• Plant new varieties next to a standard for your area
• Observe for at least two harvest seasons before “buying in”
• Get customer feedback

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Site Selection

Exposure

• Full Sunlight
• Protected from wind
  • Windbreaks
• Run rows North to South
• 0 to 8% slope

Soils

• Many types acceptable
  • Sand to silt, but not clay
• Well-drained
• High % organic matter
  • (4-6% or more)
• Soil pH: 6.0 to 6.8
• Take a soil test!

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Site Preparation

Soil Test

• pH, nutrients, o.m.

Soil Amendments

• Lime, dolomite, sulfur
  • Modify pH to 6-7
• Fertilizer (N-P-K)
• Organic Matter
• Compost, manure

Eliminate Weeds

• Tillage
• Herbicides
• Pre-Plant Cover Crops
  • ↓ Weeds
  • ↑ Organic Matter
• Fallow

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Planting Grapes

• Use 1-year old plants
  • Bare root or potted
    • $5-10 ea.
    • 600 to 800/acre
• Soak roots before planting
  • 1-3 hours (don’t drown them)
• Plant at nursery depth
• No fertilizer!
  • Add compost to backfill
• Support stake
• Prune to 1-2 shoots
• Water in
• Apply grow tubes?
  • 3.5” dia. x 30” height
• Mulch: ↑ moisture, ↓ weeds
  • Woodchips, bark, plastic
• Remove in fall
  • Sun & mouse damage
• Spacing:
  • 8-10’ between plants
  • 8-14’ between rows
  • 600 to 800/acre
• Use stakes or string to train shoot up to trellis wire (or grow tubes)

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Establishing the Vineyard

• Establish sod between rows
  • Fall prior to planting
    • Eases planting activities
    • May compete with vines
  • Fall after planting
    • No competition
    • Must control weeds
  • Use slow-growing lawn mix
    • Hard fescue/bluegrass

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Trellising Grapes

• Endposts
  • Set at least 2’ deep
  • Angle away from row 45º
  • Anchor with wire
• Posts every 24’
• Attach two trellis wires
  • At heights of 2.5’ and 5’
  • #9 galvanized wire
    • Adjustable tension

(Click on thumbnails to view enlargements.)

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Irrigation

• Adequate water is critical!
  • Establishment
  • Fruit sizing, quality
• Avoid watering foliage
  • Encourages disease
  • Wastes water
• Trickle or drip systems best
  • Require less water & pressure
  • Require clean water
    • Filters

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Training Grapes

Video: Caring for Young Grape Vines (YouTube)

Video: Four Arm Kniffin System for Growing Grapes (YouTube)

 

Trellis: 4-Arm Kniffin

• Two Wires
• Low wire, 3 feet
• High wire, 5 feet

First Year:

• Remove all but one strong cane
• Cut remaining cane to 2 buds
• Tie to stake for support

Second–Third Year:

• Train trunk to the top wire
• Remove all shoots between wires
• Cut shoots on the low wire to two buds

Mature Vines

• 4 to 6 canes (1-year-old)
  • 5 to 12 buds each
• 4 to 6 renewal spurs
  • 2 buds each
• Total 40-60 buds per plant

(Click on thumbnails to view enlargements.)

Video: Umbrella Kniffin System for Growing Grapes (YouTube)

First – Second Year:

• Remove all but one strong cane
• Cut remaining cane to two buds
• Tie to stake for support

Second – Third Year:

• Train trunk to the top wire
• Remove all but two shoots at top of the trunk
• Drape over top wire, secure to low wire

Mature Vines

• 4 canes (1-year-old)
  • 10 to 12 buds each
• 2 to 4 renewal spurs
  • two buds each
• Total 40-50 buds per plant

Click on images to view enlargements.

Tender Varieties & Cold Sites

• Bend 1st-year shoot 90º for ~12”
• Bend back up to form “hinge”
• Use stakes & wire to train shoot
• Pull plant off trellis in fall
  • Hinge allows trunk to bend
• Cover with soil or mulch
• Return to trellis in spring

Fan System or VSP (Vertical shoot positioning)

First – Second Year:

• Remove all but one strong cane
• Cut remaining cane to two buds

Second – Third Year:

• Shorten two canes to 3-4 buds
  • Remove all others
• Tie 2-4 canes to wires
  • Spread to fan pattern

Mature Vines

• 4 to 6 canes (1-year-old)
  • 10 to 12 buds each
• 2 to 4 renewal spurs
  • 2 buds each
• Total 40-50 buds per plant

(Click on thumbnails to view enlargements.)

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Growing Grapes

Walls, fences, arbors, etc.

• Protected, full sunlight
• Keep trunk, canes low
• Lower and cover for winter
• Prune to 40-60 buds/plant
  • 5-15 buds/cane
  • 4-15 canes or spurs/trunk

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Pruning Grapes

December – March

• When canes are fully dormant

Prune out

• old canes (2+ years)
• weak canes
• injured\diseased
• “bull wood” (> ½” thick)

Select 1-year old canes

• 3/8” diameter
• Chocolate brown
• Healthy (green interior)

Retain 1-6 fruiting canes

• 5-12 buds each

Retain 2-6 renewal spurs

• two buds each

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Fertilizing Grapes

• Maintain pH at 6-7
• Soil test every two-three years
• Spring
  • Apply ~ 2oz. N, 1 oz. P & K
  • Or ½ lb. 10-6-4 per plant
  • ~20 lbs. N per Acre
• Mid-June
  • Repeat application

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Harvesting Grapes

Long Season Crop

• 120-160 frost-free days
• Color before ripe
• Need to develop sweetness
  • Brix: 15-20+
• Test by taste
  • Won’t improve postharvest
• Yield 0-25 lbs. per plant
  • 0-4 tons/acre
  • 12 lbs. yields ~ 1 gal. juice

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Grape Problems

Winter Injury

• Dry, light brown or gray canes
  • No green within canes
  • No green within buds
• Labrusca types
  • -15 to -20º: bud & cane injury
  • -25 or lower: trunk injury
• Vinifera hybrids
  • 0 to -10º: bud & cane injury
  • -15 or lower: trunk injury

Weeds

• Most significant pest
• Delay establishment
• Reduce plant growth
• Reduce yield and quality
• Harbor insects and diseases
• Management
  • Eliminate pre-plant
  • Cultivation
  • Mulch
  • Some hand-pulling will be necessary!

Diseases

• Caused by fungi
• Favor moist environment
• Management Keys:
  • Good air circulation
  • Good pruning
  • Sanitation
  • Fungicides?

Black Rot

• Management
  • Good air circulation
  • Good pruning
  • Sanitation
    • Remove mummies
  • Fungicides
    • Apply spring to ripening
      • Flint, Pristine, Ferbam
      • Copper

Botrytis Bunch Rot

• Management
  • Good air circulation
  • Good pruning
  • Sanitation
    • Remove mummies, debris
  • Fungicides
    • Apply spring to ripening
      • Captan, Pristine, Elevate
      • Copper

Downy Mildew

• Management
  • Good air circulation
  • Good pruning
  • Sanitation
    • Remove debris
  • Fungicides
    • Apply late spring to ripening
      • Prophyt®, Pristine®,
      • Copper, Sulfur*

Powdery Mildew

• Management
  • Good air circulation
  • Good pruning
  • Sanitation
  • Fungicides
    • Apply at first sign of infection
      • Pristine, Sovran®, Flint®, Procure®
      • Copper, Sulfur*

Insects

Management Keys:

• 

  Keep plants healthy

• Remove alternate hosts
  • Especially weeds

Management Options:

• Hand picking
• Predators/parasites
• Sanitation
• Insecticides

Japanese beetle

• Feed on leaves, fruit

Management

• Hand picking
• Insecticides
  • Sevin®, Assail®
  • Neem, Surround®
• Traps: ineffective
• Grub control: ineffective

Leaf Hoppers

• Feed on leaf underside

Management

• Sanitation
  • Remove debris
• Insecticides
  • Provado®, Assail®, Sevin®
  • JMS Stylet oil®

Phylloxera

• Cause galls on leaves
• Usually not significant

Management

• Remove infected leaves
• Insecticides
  • Malathion, Sevin®

Spray Schedule

Spotted Wing Drosophila

Symptoms:

• Prematurely rotten fruit
• Small, white maggots

Management

• Traps for flies
• Clean up all rotten fruit
• Insecticides
  • At first sign of damage
  • Delegate

Birds

• Netting
  • Best method
  • Costly
• Visual deterrents
  • Scarecrows, owls, tape
  • Set up at ripening
  • Move often
  • Combine with noise

Herbicide (2,4-D) injury

• Grapes very sensitive
• Avoid lawn/brush herbicides
  • Spray & granular
• Talk to your neighbor?

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Maine Grapes: Bottom Line

High Risk Crop

• High establishment costs
• High labor demands
• Winter injury likely
• Challenging pest complex
• Difficult to get high quality
• Questionable market
• 4 to 5 years to production

• High establishment costs
  • 10,000-$15,000/A
• High maintenance costs
  • $3000/year
  • Mostly labor
• Returns can be variable
  • $0-1000 labrusca
  • $0-2000 hybrids

Optimistic View:

• New hardy varieties
• Global warming
• Market for local produce
  • Specialty items
  • Wine, juice, jelly, vines
• Fun to grow!

Good luck!

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Grape Resources

Cold Climate Grape Production, University of Vermont, UVM Grapes: Horticulture