2007 Annual Report for FNC06-619
Microclimate Enhanced Movable High Tunnel with Retractable Top
Summary
OBJECTIVE
To create a microclimate that will divert wind over crops by combining existing terrain features with a retractable top high tunnel that includes thermal mass features. This will incorporate the best Mother Nature has to offer while providing additional options for environmental control and year round production of quality, healthy, local produce with minimal use of nonrenewable energy.
This farm grows fruits and vegetables for commercial production in south central Kansas. The farm has a limited amount of trees, which is characteristic of the area surrounding this farm. Planted windbreaks take years to establish, so are not a feasible short and mid-term solution. The wind and temperature extremes have a detrimental effect on the crops growing in a field setting, thus lowering the quality and quantity of production. The wind also damages the equipment, as the winds consistently reach 20-35 mph with 35-55 mph gusts. Our area is one of the most highly sought by the wind power community because of the persistent and high winds.
This project will address two problems collectively -- the adverse wind conditions and increasing the quantity of high quality food crops. Construction of an innovative retractable top, moveable high tunnel that incorporates thermal mass elements will address both problems. First, to address the action of adverse wind conditions, the wind will be diverted over the crops and equipment by utilizing the high dirt berms of existing dry ponds. Secondly, the quality and quantity of crop production will be increased through the use of the retractable top high tunnel inside the dry pond and the modified microclimate a protected pond creates. The rationale for using a retractable top for the high tunnel is to combine the best growing conditions of Mother Nature and the best conditions of a modified environment in less than ideal weather conditions. These substandard conditions are high light intensities in the summer, untimely frost dates, wind, heat, disease, untimely rainfall, and pests.
WORK ACTIVITES
Here at Peaceful Prairie Farm we grow commercial fruit and vegetables for a marketing plan called Community Supported Agriculture (CSA) as well as for a local farmers market. Currently, the work week plays out as closely as the weather will allow us...
Monday through Tuesday – Cultivating, weeding, fertilizing, and any repair to a system that may need to be done.
Wednesday through Friday, preparing for the deliveries by harvesting, grading, cleaning, and packaging the produce and then preparing the delivery boxes for the members to pick up.
Drop off points are then attended on Saturday at three local towns. If any surplus is available, we can sell it at the farmers market. This year due to the early start the tunnel afforded us for the crops, we heard many praises on the early crops we get from our customers, as well as our CSA members.
RESULTS
This past winter we set up a tunnel in a field setting and were preparing a pond for the second tunnel. Due to a time constraint and problems getting the pond to drain properly, we were only able to get one tunnel set up in the field. We were able to take temperature readings in both places and found that the temperature at the bottom of the pond was approximately 1-2 degrees cooler in the early morning. Due to less wind chill we found that the temperature was able to recuperate and actually beat the field temperature by mid morning. This meant there would be less wind chill on the plants themselves. Once the sun rises in the winter months, in the pond the temperature rises approximately 1-2 degrees more in the early morning, and the temperature then stays at least 2-8 degrees warmer throughout the day. The plants respond earlier in the morning to the warmer temperature than the plants in the field setting. Row covers can be removed approximately 30-45 minutes sooner each day than over the plants in the field setting also.
We were able to deliver greens as a winter session for our CSA members during the months of February, March and April in our area because of the added protection that the tunnel offered. The use of the second layer of row covers was imperative however.
Because of being in the middle of the project, we were not able to set up the thermal mass option at this time. During March we had an abundance of wind and the wind did some damage to the tunnel, so we took it down and did the needed repairs to it and are now preparing to set them up again in the fall. We found that the movable portion of the tunnel will not be able to be utilized in the field setting due to the winds we get throughout the winter months. We have not been able to experience any summer performance thus far, and with the high moisture we had this year we found that it will be imperative that we utilize the roll top feature of the tunnel in the future for ventilation. This we found from other people who had conventional greenhouses in the area. There has been a problem with blight in tomatoes, and mosaic in the melons.
WORK PLAN FOR 2008
Currently we are waiting for the remaining funds of this project to purchase the parts for the retractable motion of the top. Thus far we haven’t been able to build this component of the project. Currently we are preparing the seed beds. We have set up a time line to do the repairs and construct tubes to incorporate the thermal mass portion of this project. Together with our CSA members we will set up both tunnels this fall (by September 15) by having a festival such as the old barn raisings called a “Hoop it UP” festival. Afterwards we will have U-Pick, a meal, and maybe some music in the evening to help the members celebrate this event. Throughout the fall and winter we plan to plant successive crops of greens, potatoes, winter squash, and transplant tomatoes and melons for the members. We will also use part of the space to market local produce wholesale to a restaurant in Wichita, KS (Hilton). The first season proved that this equipment works well as a great tool for extending the season for local produce, and greatly supplements the produce for our CSA.
OUTREACH
Approximately five members of our CSA were some of the people who viewed the use of the tunnel, and people from local philanthropic groups have come to view the farm as well as the tunnel. We have had approximately 18 people here to visit the farm while the tunnel was in action. All found it very informative, and something they have stated is not a common site in this area. Our CSA members benefit from the tunnel directly during each off season delivery.
Next year, we plan to invite children from the local school district, for a learning session, and more of our members for other festivals. We will try to once again invite our local KSU Extension agent out to view the tunnels in action. He was very busy last year and couldn’t find a time to come out while the tunnel was up.