This is Part 2 of a five-part series on On-Farm Variety Trials. Part 1: “What’s the fuss all about?” can be found here.
In my last blog, I introduced the concept of on-farm variety trials and explored the many benefits of conducting one on your farm. Today, I will explore the planning and preparation stage of the process. As with any project, thorough planning from the start will set up your variety trial for a smooth and enjoyable execution.
Identifying Goals
The goals you set for the trial guide every decision and process you undertake such as where and when to plant, how you manage the crop, the size of the trial plot, when to evaluate to crop, what data to collect, and how the data is interpreted.
What do you want to learn from this trial? Why are you doing it? What problem are you trying to solve?
Common trial goals are to find a variety that:
- Is pest resistant;
- Replaces a lost or discontinued variety;
- Has certain culinary characteristics;
- Has desired agronomic characteristics like higher yield, early vigor, or drought tolerance;
- Matures in a desired harvest window.
University of Illinois Extension Agent Bill Davison is quite known for his corn variety trials. As a member of the Artisan Grain Collaborative, he has used variety trials to identify excellent flavor and cooking properties in heirloom varieties for corn meal.
[Photo credit: Bill Davison’s Local Food Frontier]
It is very tempting to set goals for the trial that can become quite complex to achieve. For your first on-farm variety trial, start small. Choose one crop that is of high value to your farm and set 1-2 goals for that crop. By starting small and slow, you will learn the variety trial process and the project will remain a manageable size while you are learning.
Choose Trial Varieties
Once you have identified the crop and your goals for it, it is time to select the varieties you will grow and compare. Using your goals and your current crop management plan as a guide, write a description of the ideal variety you are striving for. In this description, include characteristics that you must have and desire, even if you are not measuring for them. It is important that the varieties you are selecting from meet your base requirements.
For example, say you are conducting a carrot variety trial and your goal is to find a carrot of superior flavor. The variety must still meet your baseline agronomic needs, fit within your management system, and meet your customer’s expectations. If your customers strongly prefer long, fat, orange carrots, and your soils are a heavy clay type, you may write the following description: “Roots grow 6-8 inches and are thick, good for clay soils, excellent flavor, 65-80 days preferred.” With your description in hand, you are ready to start the search for your trial varieties.
Cast a wide net when looking for sources of seed, you may be pleasantly surprised by what you find. Search online and print seed catalogs. Talk to seed dealers in your region. Reach out to your area universities and extension service to gain insight into varieties they have trialed. All the while, be sure that the varieties you select reasonably fall within your desired description. In the end, you should select 3-10 varieties for your trial.
The Check Variety
For each variety trial you conduct, it is important to include a variety that you know best, known as the “check” variety. This variety will serve as a barometer for comparing your test varieties and for comparing your trial year to other growing years. Your check variety will help you determine if the performance you see out of your trial varieties will typical of average performance. If your check variety does not normally suffer disease but is diseased during the trial, that will help you interpret the presence of disease in your test varieties.
The check variety serves as a baseline for comparison. You will be able to compare the measurements of all of your goals against your check variety to determine if your test varieties are improvements or are not worth the risk at full production levels.
Lastly, the check variety also can help with communicating your results. If your check variety is well known, it is easy to use it as a comparison for other farmers to understand your experience. If you say the flavor of your test carrot variety is better than Scarlet Nantes, many people will understand and may be intrigued. But if you say your test variety is more flavorful than Granny Argyle’s Purple Carrot, the comparison is not as effective.
Creating the Work Plan
With your goals, test varieties, and check variety in hand, you are ready to develop the work plan for your trial. To create your work plan, gather a few more pieces of information. You’ll need:
- Estimate of the time you have available to evaluate the trial during the part of the season when you will be measuring the performance of your chosen varieties;
- Map of the field where you will be planting;
- Plant spacing and planting needs;
- Harvest plan;
- List of the characteristics you will be measuring;
- Timeline of the work flow for the trial;
- How you will document the data you collect.
Set up your trial system at the start of the process. Once the season is going, it will be difficult to carve out time to make decisions and set up record keeping systems. With everything set up from the start, you will likely be more successful in tending to your trial and collecting your measurements.
The Organic Seed Alliance’s Grower’s Guide to Conducting On-Farm Variety Trials contains a comprehensive planning template in Appendix A that is very helpful in setting up your variety trial plan.
In the next month’s blog, I will discuss designing the variety trial including types of variety trial structures, plot layout, replication, and best management practices for variety trials.