Comparison of Coverings Over Permanent Raised Beds to Extend the Growing Season for Year Round Food Production

Comparison of Coverings Over Permanent Raised Beds to Extend the Growing Season for Year Round Food Production

Summary

WORK ACTIVITIES
• HOBO with micro-stations (4), software, shuttle, soil temperature sensors (8), air temperature sensors (8)
• Quick crete (18) 80 pound bags
• One inch PVC 45 degree elbows for inside arch
• Three quarter inch coupling for seating above elbow in vertical pipes in concrete
• PVC cement
• 6mm 4-Year Greenhouse Film
• 3 MIL 1 Year Clear Greenhouse Film
• Spun Bond Frost Blanket/Row Cover, 14 mil, 2 oz. per square yard
• 1”x 300’ NSF PE 195 psi plastic coil pipe

The above budget items were purchased and installed to complete and cover the beds. Bed preparation was completed through the installation of the concrete, pipes, and randomly assigned combinations of row covers. Ongoing work with the hobo system is learning the software, correcting moisture leakage, recording and graphing temperature data.

RESULTS
Seeds planted for the four crops were planted in late August. Germination was good and plants were healthy and robust. Vigorous growth required fall harvesting of some greens to keep growth inside the cover dimensions.

Photos taken in December document plant health. By January the control bed was frost killed, except for the onions. Plants in both single cover beds were also frozen except for the onions. Other beds had some live plants, though not of saleable quality. Persistent and severe cold prevented opening the beds for closer monitoring.

Hobo micro-station installation and use has been challenging. Software requires much self instruction from the manual which was available as a download from the internet. Design of micro-stations requires creative placement to allow access to data port while also preventing moisture contamination.

This has been an unusually cold and snowy winter. The severe cold and heavy snows have resulted in delayed data collection. Row covers have been sealed on the beds with snow and ice. Below freezing temperatures have prevented safe entry into the beds. As late as February 21, 2010 we received 9 inches of snow. On February 24th it was zero degrees Fahrenheit with a wind chill of -9. Temperatures have been consistently below seasonal average by as much as 20 degrees. The unusual conditions prevented correlating plant response to the temperatures obtained. Conclusions will be primarily based on the end result rather than specific winter temperature events.

Warmer temperatures are predicted for the second week in March. The beds will be opened as soon as safe entry is possible and photos taken to document condition of plants following the brutal winter.

I have created a technique for marking the beds for identification in photos which include large stencil letters in the photo with date printed on each photo.I will reinstall the microstations on a hinged board to allow access to data port with greater convenience.

WORK PLAN FOR 2010
• I plan to continue to become more proficient with the data collection instruments and software.
• I will purchase and install the irrigation kits.
• I will document plant survival with photos and recovery counts (if there was plant survival).
• I will plant/replant the beds for seasonal production and replant the beds (based on plant survival) for season extension in fall 2010.

OUTREACH
• Twenty people attended a Farm Tour in September and were given an introduction to the project in its early stages.
• Two NRCS staff were briefed on the study during a farm visit.
• Two Lincoln University Extension staff toured the Farm during January and were presented with an orientation to the project.
• A photo of one of the project beds was published in a GRIT Magazine winter growing article.

Next year: This project is best suited for a workshop presentation which will document the stages of bed construction, planting, covering, data collection and results with photos throughout the growing season and winter weather events. I will submit proposals to present at one or more farmer/grower events (Missouri Organic Association, Great Plains Vegetable Conference).

I will post a project summary on my web site.

Collaborators: