HIGH TUNNEL/COLD FRAMEGARDENING

Extending the growing season

Kevin Heaton

Utah State University Extension

Kane and Garfield Counties

...if it can be done in Panguitch... it will work anywhere!!!!

• Why High Tunnel/Cold Frame Gardening• Available Tunnel Options • Tunnel Research and

Demonstrations

Why High Tunnel/Cold Frame Gardening

• Utah’s cool, short growing seasons• Earliness offers price premiums• Improved climate management• Season extension expands production

window• Expanded opportunities for different crops

Some of the benefits

• Can cost as little as $0.50 per square foot

• Covered with a single layer of plastic• Tall enough to walk-in • Size: 14-30 feet wide 30-96 feet

long• Grow in ground beds• Erected on skids

• Passively ventilated• Generally not heated• Tunnels in tunnels give more protection• Production during fall, winter, early spring• Shaded in summer• Protect plants from wind and rain

How does it work? The original “greenhouse effect”

Planning and Construction

• Good sunlight• Wind Breaks

– Height, Density, Orientation, Length• Avoid shadows

– E-W = 20 ft– N-S = 5 ft

• Water source• Site Selection

• Wind Directions• Soil Issues• Water Quality• Access to other operations and buildings

Rib, Hoop, Arch, Bow

End Wall

Hip Board

Side Wall

Baseboard

Purlin , Ridgepole

Construction Issues

• Structural framing for support• Type/shape influences strength

– Metal/PVC ribs– Spacing of ribs

• Covering Materials– Plastic– Shade cloth– Other

• End walls - Access and Ventilation • Removable sections in summer• Fixed/roll-up walls • Fixed walls – winter• Roll-up walls - Vent

Wind Damage--Logan

Panguitch Cold Frame Demonstration

The Plan

• Planted Feb 20, 2006 and Mar 4, 2006– Lettuce, Mesclun, Turnips, Peas, Carrots,

Broccoli and Cabbage.– Twelve 55 gallon barrels filled with water– First harvest

(thinning): March 27• Plant May 15-20

– Warm Season Crops• Plant Oct 1-15

– Cool Season Crops

Average Temperatures

• Average Minimum– Outside 11 ° F – Inside 24 ° F – Difference 13 ° F

• Average Maximum– Outside 63 ° F – Inside 98 ° F – Difference 36 ° F – Highest Maximum Inside 120 ° F

At what temperature do plants freeze?

• Cool Season “Very Hardy”– Peas, Cabbage, Broccoli, Onions, Lettuce,

Radish, Turnips and Spinach– Germination 35-40° F, Survive 20 ° F

• Cool Season “Semi Hardy”– Beets, Carrots, Cauliflower, Parsley, Potatoes,

and Swiss Chard– Germination 40-45 ° F, Survive 25 ° F

At what temperature do plants freeze? (cont.)

• Warm Season “Tender”– Beans, Celery, Corn, Cucumbers, and

Summer Squash– Germination 50-55 ° F, Survive 28-32 ° F

• Warm Season “Very Tender”– Cantaloupe, Egg Plant, Pepper, Pumpkin,

Winter Squash, Tomato, and Watermelon– Germination 60 ° F, Survives 32 ° F

Temperature Data – Lowest Difference

Date Min-Out Min-In Difference

Mar 15 17.2 19.1 1.9

Mar 26 28 32 4

Feb 21 -5.1 -1 4.1

Feb 22 -1 5 6

Mar 4 26.8 33.6 6.8

Temperature Data – Lowest indoor

Date Min-Out Min-In Difference

Mar 13 -14.1 15 29.1

Mar 14 -8 16 24

Mar 15 17.2 19.1 1.9

Mar 16 4.5 22 17.5

Mar 23 12.2 22.6 10.4

Mar 13 – Min Temp 15 ° F

March 28, 2006

April 5, 2006

Warm Season Plants 2006

2007

• Planted January 27, 2007– Lettuce, Radish, Turnips, Peas, Carrots and Cilantro– First harvest: March 18, 2007

• Planted Feb 17, 2007– Radish, Turnips, Peas, Lettuce, Cilantro and Broccoli

• May 15-20– Warm Season Crops

• Plant September 1st– Cool Season Crops

Soil Temp Min/MaxSoil Temperature Min/Max

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degr

ee F

Soil Temp Min Inside

Soil Temp Max Inside

Outside Soil Temp AVG

Soil vs Water TemperaturesSoil vs Water Temperature

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10

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60

70

80

Date

Deg

ree

F

Soil Temp Min

Soil Temp Max

Water Temp Min

Water Temp Max

Air TemperatureAir Temperature

-20

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120

140

Date

degr

ees

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Inside Temp Min

Inside Temp Max

Outside Temp Max

Outside Temp Min

March 27, 2007

March 27, 2007

March 29, 2009

March 29, 2009

2013

Spinach--Planted 12/24/13

Planted inside the 2nd house

Planted inside the 3rd house w/frost blanket

Carrots – Planted 12/24/13

Planted inside the 2nd house

Planted inside the 3rd house w/frost blanket

The end!!!