When the Great Outdoors Just Isn t Quite Enough. Our Time Today 7/6/2017 WHAT CAN A HOME GREENHOUSE DO FOR YOU?

Transcription

1 When the Great Outdoors Just Isn t Quite Enough Dr. Natalie Bumgarner UT Residential and Consumer Horticulture Specialist/ TEMG Coordinator IMGC Our Time Today A little Q and A to begin What can a GH do for you? Location, location, location The basic foundation (geek) The real foundation (practical) Putting it all together Section 1 WHAT CAN A HOME GREENHOUSE DO FOR YOU? 1

2 Grow garden transplants Wide cultivar selection Control over health Choose your own timing Plant benefits of natural light Winter hort therapy Dedicated poinsettia reusers Grandma s geraniums Figs Tropical fruits Overwinter plants Maintain specialty crops Many, many options Orchids, bonsai Many facets/techniques Can be less costly than lights and equipment indoors Parshotam Lal Tandon 2

3 Extend the season Economical Pairs with garden Early warm season Early and late cool season harvests Limits weather issues Can reduce disease v. outside Photo credits OSU/OARDC VPSL Grow food (closer to year-round) Leafy crops Herbs Tomatoes and cucumbers Faster production Exclude pests Enhance quality Section 2 THE THEORETICAL FOUNDATION 3

4 How much control is enough?? -Permanent -Completely passive heating and cooling -Permanent -Active heating and cooling 4

5 -All the bells and whistles WE HAVE TO ADDRESS GEOGRAPHY Section 3 Temperature Winter min Summer max Plus humidity maps/city?3&wmo=06451&info=0&pa G=0&LEVEL=160 5

6 Light My one allotted geeky slide NASA.gov The real heart of the matter Lightneeded heat and energy Light excess energy and heat 6

7 Management aspects Climatic limits Equipment Air space Management tools Section 4 THE REAL FOUNDATION Consider the costs Location- utilities, zoning Materials Heating and cooling management Maintenance How do you value the benefits? 7

8 How large? Considerations Season Crop needs Space available Why? Temperature changes Cost Efficiency Site and Orientation Light and wind Shading Season E/W can maximize early spring light N/S is more year round Wind movement cooling Also consider crop Image credits: Sean Pyle Frame Steel Aluminum Wood Consider shape 8

9 Covering Consider: Light Life Weather Heat loss Glass light heat loss humidity structure lifespan cost Rigid Polycarbonate common Range of thickness/type heat loss humidity moderate structure lifespan moderate cost Plastic Flexible PE (2x) most common heat loss humidity moderate structure lifespan cost maintenance 9

10 Covering comparisons Light transmission*,** Suitability for hail/ice Heat loss in Btu (U value)** Single layer glass 90 92% Reasonable 1.13 Double layer glass 81 85% Reasonable 0.70 Single layer polyethylene 87% Poor 1.20 Double layer polyethylene 76% Poor mm polycarbonate 79% Reasonable mm polycarbonate 77% Reasonable 0.58 Acrylic 8 mm (2 layer) 83% Reasonable Corrugated FRP 88% Reasonable 1.20 * light transmission is PAR values from American Society of Agricultural Engineers 1995 (**reported in Greenhouse Operation and Management Edition 6) Floors Concrete- easier to clean, higher cost Gravel- porous, harder to clean Brick or stone Ventilation Open sidewalls Passive vents Exhaust fans Horizontal air flow Vertical air flow 10

11 Heating method Gas (vented or unvented) Propane Heating and cooling Evaporative cooling Wet wall Mist, fog Connections to light management Heat control by light limitation Which is most limiting? Controlling light Shade cloth Shade paint Manual/permanent 11

12 Environmental Controllers How much control? How much precision? How much remote access? Image credits: Alex, Flickr Section 5 BRINGING IT ALL TOGETHER Step 1. Know your goal 12

13 Step 2. Be realistic Do I really have a site on the property? Time/management ability? What is the intended lifespan? Benefit or detraction to others? Step 3. Decide based on feasibility and utility Not Can I? But Should I? Image credits: NASA The quadrant of control Growing food crops year round (GH) High control Wide seasonality Specialty crops (orchids) High control Moderate seasonality Growing food crops off season (GH) High control Moderate seasonality Overwintering tender plants Moderate control Moderate seasonality Growing transplants Moderate control Limited seasonality Growing food crops (high tunnel) Low control Moderate seasonality Growing food crops (low tunnel) Low control Limited seasonality 13

14 Growing garden transplants Focus on heating Limited cooling needs Pest exclusion needs may be minimal Want all the light possible Must have good control of temp (bright day ventilation) Watch unvented heaters Specialty crops Could require a high level of specificity Heating and cooling needed Potentially year round Light, humidity control likely needed Parshotam Lal Tandon Extending the season It is all passive Be aware of temperature benefits Day>>>night Choose crops accordingly Understand the attention needed to manage passive systems well Photo credits OSU/OARDC VPSL 14

15 Producing vegetables year-round Temp control Humidity control Light is critical Pest exclusion Scouting Consider pest control in construction Cost vs. benefit? In Conclusion Know your goal first Be familiar with the basic principles Consider initial investment, lifespan, and desired management level Then decide on system Have fun! 15