By Lynn Byczynski
Fortunately, science has come to the rescue of garlic growers and provided some definitive information about the confusing subject of garlic varieties. Now it’s known that all varieties can be sorted into 10 basic types; that there is a great deal of duplication among the so-called varieties; and that many with different names are genetically very similar. It’s also known that some of garlic’s most important traits are determined by location, soil, climate, and the skill of the grower.
For beginning garlic growers, here are the basics :
Sorting through the names
In 2003, Dr. Gayle M. Volk of USDA’s National Center for Genetic Resources Preservation in Fort Collins, CO, did DNA fingerprinting of 211 varieties of garlic. Many were so genetically similar as to be statistically the same. However, she found that there are 10 distinct types: silverskin and artichoke are the two softneck types; rocambole, porcelain, purple stripe, marble purple stripe, Asiatic, turban, creole, and glazed purple stripe are hardneck types.
“Clove arrangement, number of topsets, topset size, topset color, number of cloves, clove weight, clove skin color, and clove skin tightness were generally stable for each cultivar regardless of production location and conditions. Soil potassium levels were positively correlated with bulb circumference and fresh weight. Soil sulfur and manganese levels were correlated with bulb sulfur and manganese content. Bulb wrapper color and intensity were highly dependent on location and cultivar. The Silverwhite cultivar was consistently white and ‘Ajo Rojo’, ‘German White’, ‘Inchelium’, ‘Sakura’, and ‘Spanish Roja’ were generally white with some faint violet or brown stripes or splotches across the locations. In contrast, cultivars Chesnok Red, Purple Glazer, Red Janice, and Siberian were more likely to have moderate or dark violet stripes, streaks, or splotches, particularly when grown at the northern Colorado, Minnesota, Nevada, New York, Ontario, Pennsylvania, or Washington locations.”
The implication for growers is that the variety you plant may look different in size and color when you harvest it, especially if you purchased it from a distant supplier. Dr. Volk’s advice is to trial a number of different varieties representing the different types. She suggests that, at the least, you grow an artichoke, silverskin, purple stripe, porcelain and a rocambole. Skilled growers can grow almost all types well, she said, so personal taste and market success may be the most important factors to consider when assessing a variety. Once you have determined the type that works best for your farm and markets, you can begin to propagate your own stock, selecting the biggest and best bulbs to plant the next year. In this way, you develop your own strain adapted to your conditions.
For detailed descriptions and photographs of the 10 types of garlic, visit www.bignewsforgarlic.com.