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CaryL.Rivard,Ph.D.

November19,2011

KRCSustainableAgriculture

Conference

HighTunnels:RealitiesandPossibilitiesHighTunnels:RealitiesandPossibilities

Photo courtesy: S. O’Connell (NCSU)

• All shapes and sizes– Three or four seaaon

• Climate Control– Season Extesnion– Use of low tunnels, etc.– Protection

• Reduced Foliar Disese

• Access to new market windows

• Production stability

Why High Tunnels?

Construction

•Site location / preparation– Soil, wind, water– HT orientation

•Plumbing, electrical, heating ?•Soil preparatation

High Tunnel / Hoophouse Construction

Prevailing winds from

the South-SW

Structure Assembly•Set the footers with precision

– Concrete ?

•Baseboards

•Bow Assembly

•Purlin Assembly

•Hipboards

•Sidewalls and Endwalls

Construction

Construction

ConstructionStructure Assembly•Set the footers with precision

– Concrete ?

•Bow Assembly

•Purlin Assembly

•Tools– Ratchet/Socket– Cordless drivers (ALOT)– Ladder / Scaffolding

Construction

Protective Eyeware

ConstructionSidewalls and Endwalls•Roll-up or Roll-down sidewalls

•Endwalls– Doors– Ventilation

•Organic certification?– Treated wood cannot touch soil

Cedar or Untreated Pine (coated with Linseed Oil)

Construction

Cedar footer tied to treated lumber

Secure Sidewalls

Motorized Shutter

• Maintain good soil quality

• Irrigation– No rain in the tunnels– Overhead irrigation ?– Fertilizer injector when possible

• Nutrient management– Similar to field– Be careful of soil salt build-up– Always use compost wisely

ManagementManaging the High Tunnel

•Manage/Ventilate sidewalls – Summer Crops – close when nights are <55oF– Winter Crops – Varies with crop/climate– Automated sidewall curtains

Hand crank for sidewalls

Note: metal brackets to hold sidewall

• Reduced foliar disease– Leaf wetness

• Foliar diseases in tunnels– Powdery mildews– Botrytis– Viruses

• Reduced crop rotation– Soilborne pathogens– Moveable tunnels

ManagementDisease Management in High Tunnels

From: G.N. Agrios. 2005. Plant Pathology. 5th edition. Elsevier AP.

Verticillium wilt - Tomato

Early Tomato Production

• Rootstock and scion are held together with a small silicon clip.

• Grafts are held in a “healing chamber for 7- 9 days”.

http://www4.ncsu.edu/~clrivard/Resources.html

Tomato Grafting

ScionScion

RootstockRootstock

Management

•Also known a “green manures”, cover crops are extremely important for soil health

– Organic matter– Soil microbial health

•Suppress Weeds•Add / Recover nitrogen

– Highly-leachable N03– Legume cover crops fix N

•Can be used as mulch– No-till or strip-tillage

•Can reduce excess nutrients (P)•Reduce soil erosion

Cover Crops

Beneficial habitat planted around the tunnel

What Crops to Grow

•Grow high-value crops that help to pay for the structure and the labor that goes into maintaining it

– $500-$800 per year (30 x 96 ft) for structure alone

– Market niche•Increase value of crops that can be grown outdoors

– Summer spinach / greens•Learning curve•Most crops do well inside

Economics

Cut Flowers

•Blackberries•Blueberries•Raspberries

•Strawberries

•Sweet Cherries

•Tree fruit ???

High-Value Small Fruit

Small Fruits

Growing apples in a high tunnel in Alaska

Blueberry yields – Olathe, 2008 (Harvest 6/25 to 7/30)

lb/acre @$6/lb

Blue Crop (Mid) In 4,368 26,443

Out 1,852 11,211

Duke (Early) In 5,203 31,496

Out 2,904 17,577

Jersey (Late) In 7,408 44,846

Out 3,022 18,296

Patriot (Early) In 7,927 47,984

Out 4,118 24,925

Sierra (Mid) In 10,200 61,745

Out 4,207 25,467

Blueberries in a multi-bay tunnel

“Three-season” has no cover in winter

• Heritage, Autumn Britten, Kiwi Gold (Nourse Farms, Deerfield, MA)

• Planted on raised bed, 2.5’ within row and 8’ between rows.

• Mulched heavily with chopped alfalfa

• Pruned to the ground, winter 2005-2006.

Raspberry Cultivar Trial

Small Fruits

Fall Bearing Raspberry – Olathe, 2007

Frt wt (g) lb/acre @$8/lb

Autumn Britten

In 1.9 3,428 27,427

Out 1.7 3,061 24,488

Heritage In 1.5 8,170 65,359

Out 1.1 5,535 44,281

Kiwi Gold In 1.4 9,015 72,116

Out 1.1 5,532 41,056

•Earlier Spring market

•Late Fall market•Planted earlier

– Shade cloth

•Day Neutral Varieties•Watch for mites

•Strawberries in KS??

Strawberries

Small Fruits

Strawberries grown in “Grow Soxx”

Cool Season Warm SeasonLettuce Tomatoes

Radishes PeppersSpinach CucumbersPotatoes MelonsOnions Sweetpotatoes

Peas PumpkinCarrots Squash

Cabbage Eggplant

Asparagus Beans

Vegetable Crops

•Cool-weather crop that is cold-tolerant•Leaf types

– Loose– Romaine or cos– Butterhead– Crisphead– Mixed greens

•Mid-March to early April•Good for containers•Aphids can be a problem

Lettuce and other leafy greens

Vegetable Crops

Use space efficiently by growing “partner crops”

Vegetable Crops

Lettuce (greens) grown in containers

•Transplants can be grown in high tunnel•Sow seeds in tunnel (late fall)•Transplant to field (late March)

Onions

Vegetable Crops

Spinach•Nutritious, hardy greens crop•cvs. Long Standing Bloomsdale, Melody, Space, Avon, Tyee•Sow directly

– Mid- to late March– August to early September

•Fertile, well-drained soil•Clip leaves when they are large enough to eat•Quick to bolt in spring

Vegetable Crops

Summer Spinach Production•39% shade•Sprinkler irrigation

•Utilize vertical trellises to maximize space•English types•cvs. Diva, Dasher, Sprint, Marketmore, Sweet Slice•Direct Sow or Transplants

– Soil temperature (60oF)– 2’ x 3’ rows

•Roots susceptible to damage•Use shears to cut off fruit

Cucumbers / Melons

Vegetable Crops

Melons - Olathe, 2005

Vegetable Crops

Peppers•Related to tomato and eggplant•cvs. Ace, Bell Boy, Jupiter, Aristotle, Valencia, Purple Bell, Karma, Jackpot•Less cold-tolerant then tomatoes

– Seedlings

•Transplants– Mid-May– 18-24” in rows 15” apart

•Fall Peppers

Vegetable Crops

•Most popular vegetable grown in the garden•cvs. MANY MANY varieties

– Heirlooms: Cherokee Purple, Brandywine, Green Zebra– (Semi) Determinates: Mtn Fresh, Celebrity, FL 91– Indeterminates: Jetstar, Better Boy, Whopper, Sungold

•Transplants– Early May to Early June– 18-24” in 3-5’ rows

•Hotset / heatset varieties– Can be grown in the fall

Tomatoes

Vegetable Crops

Come and visit any time

Cary Rivard, 35230 W 135th St., Olathe, KS 66061 913-856-2335 ext 120; crivard@ksu.edu