Dr Desmond Layne, associate professor of pomology, tree fruit specialist, and state program team leader for horticulture at Clemson University

Stone Fruit

Establishing A Variety "Test" Block

Desmond R. Layne
dlayne@clemson.edu

Have you ever planted a particular stone fruit variety that you thought was going to be a winner and it later turned out to be a loser?  At the time you made the decision to plant that variety, were you adequately informed?  If not, what information were you lacking?  Have you since calculated the economic loss that you incurred as a result of your decision?  Learning from and not repeating mistakes of the past is a sign of wisdom.

Whether you produce a few acres of stone fruit for a local retail market or several thousand acres for distant wholesale markets, variety choice is absolutely critical to the long-term profitability of your business.  It is not a decision that should be made hastily after spending a few minutes looking at the pretty glossy photos and reading the appealing descriptions in the latest nursery catalog.

In the current “information age,” we have access to more information than we often want or need.  A key question to ask about any information on the Internet is whether the information is suitable for your specific climate and location.  Another key question is whether the information source is biased or not.  Often, Extension and research faculty from the local university are the best source of unbiased information.  Stone fruit growers from your region who are not in market competition with you may also help you greatly.

Know Your Variety

Variety performance is based on the inherent genetic potential as well as on environmental conditions.  Before choosing new varieties, there are several questions to ask: Where was this variety developed (i.e., state, climate type, chill hours)?  What type of market was it developed for (i.e., local fresh, distant shipped, processing)? Has it been grown or tested widely in your region (i.e., university or grower experiences)?  What are its primary strengths (i.e., taste, color, size, reliability, niche potential)?  Does it have any significant weaknesses (i.e., inconsistent cropping, poor color, splits, disease susceptibility)?

If you have no personal experience with the variety in question, you take the risk of basing your decision upon the information of others.  I would encourage you to consider reducing your risk.  So the question remains, how?  Why not plant a variety “test block” on your own farm and do the evaluating yourself!

What should the test block include?  First, you need industry “standard” varieties spanning the harvest season.  These standards have been accepted in the trade and there is a historical record of their past performance.  These should include varieties you are already growing on your farm that will serve as a benchmark for comparison.  Second, you need quality nursery trees of the new varieties you want to test.  Choose these wisely after consulting various sources.

Several key components are necessary for a good test block.  First, choose a good site in a prominent location where you are forced to drive past it daily.  Second, plant enough trees of each variety so that you get a good “test” (no less than 10 per variety).  Third, plant trees at high density (i.e., perpendicular V, 400 trees per acre) to minimize the land area and time required for walking through the orchard.  Fourth, lay rows out in a serpentine pattern based on ripening date (earliest variety first, latest variety last).  Fifth, manage this orchard according to your standard practices (i.e., pruning, thinning, fertilization, pest management, etc.).  Sixth, keep accurate written records of your observations (i.e., bloom date, ripe date, set, size, color, etc.).  Walk the orchard two to three times per week during the season.  Make side-by-side comparisons of standards and new varieties as the season progresses.  Take pictures.  After three to five years of cropping and evaluating, then make some informed decisions!

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This column by Dr. Desmond R. Layne, “Establishing a Variety Test Block”, appeared in the January 2005 issue of The American Fruit Grower magazine on page 47.

Desmond R. Layne, Ph.D., is an associate professor of pomology, tree fruit specialist, and state program team leader for horticulture at Clemson University. He is also president of the American Pomological Society.

For more information, go to www.clemson.edu/peach.