Time to grow crops vs. day of year planted, part II

Time to grow crops vs. day of year planted, part II

Summary

Diversified farms grow many crops. Planning a constant supply of many crops is a challenge because time to maturity varies throughout the season, and there are no planning tools to help growers predict time to harvest. This project measured the time to harvest for many plantings of 2 varieties of lettuce, one variety of broccoli and one variety of corn in 2011 (previously funded SARE Farmer grant FNE11-718) and 2012.

Grocery store, farm stand, and restaurant customers want a steady supply of “every” crop. Scheduling plantings for constant supply of crops through the year is a major planning question for growers. As climate change becomes more prevalent, this will become even more important. The main variables are seen to be temperature above the plants “base growing temperature”, and the amount of light as the calendar year progresses. The temperature is the largest variable, year to year.

As more growers practice winter growing, these issues will become even more pronounced. Winter growing will not be addressed by this specific proposal, but the methods and equipment should be useful.
This is the second year of this Project. The data from the first year shows encouraging results. The second year will add more validity to the database and give a better idea what the base temperatures are for growing.

The data taken in 2012 was essentially the same as 2011. We had three data loggers in the field taking temperature measurements, and 14-24 plantings of each crop. There were minor changes, for both lettuces we added 4 plantings in the fall so that we were seeding every 3-4 days (twice per week) rather than once per week, we did this based on the results for 2011 that showed that a few days delay in seeding (toward the end of the season) could have large effects on when, or even if, the crop matures. We also added 2 plantings of broccoli (19 total). We made no changes to the seeding schedule for corn.
One other addition to the data set was that we placed the corn data logger in the seeding greenhouse from March to June. We will see if that data is useful.

Accomplishments/Milestones

The date seeded to average date harvested plot for lettuce, Figures 1-4, shows that the results of the two years are generally the same. There are abnormalities that are hard to explain at this writing.

The date seeded to average date harvested plot for Everest broccoli, Figures 5-6, shows that the results of the 2012 season is about 1 week behind at mid season. Missing data mid season was due to intense flea beetle disease and weed pressure in several plantings. These plantings did not produce any marketable crop.

The date seeded to average date harvested plot for Mystique corn, Figures 7-8, shows that the results of the two years are generally the same. The first two plantings froze April 28 in a late hard freeze (row cover was not sufficient to protect the crop). The middle to end of the season was marked by intense weed pressure causing crop markers being lost in the weeds, and the corn temperature data logger being mowed with a rotary cutter.
Based on these results we will be eliminating several end of season plantings. We will also be changing our rotation schedule and have improved our weed control to avoid some of the pest, disease, and weed issues that we had in 2012.

Temperature Data from the data loggers show that the weather for 2012 was warmer than 2011.

Average temperature 2011 2012
40 F base, average method Avg temp:4,468 GDDf 2011: 4,808 GDDf 2012: 4,837 GDDf
50 F base, average method Avg temp:2,603 GDDf 2011: 3,114 GDDf 2012: 3,312 GDDf
60 F base, average method Avg temp: 1,309 GDDf 2011: 1,810 GDDf 2012: 2,127 GDDf

In 2012 we added 3 acres of new land that was cropped, plus 2-3 acres of new land that was cover cropped for the year, so we had about 12 acres of crop land, and 3 acres in cover crop. We also cut a new field from existing wood land, this field should be ready for cropping in 2014. We added heat to a 2nd greenhouse, added drainage to the original field, and purchased a 2nd tractor which will be used primarily for weed control.

• Charts for Annual report

Collaborators: