Dear Matthew Alice: Now that cherry season is here, I have to know where those “Siamese twin” cherries come from — the ones that have a single stem but two cherries stuck together. — J. Moore, Coronado
We’ve meddled with the genetics of the cherry tree enough that some of the resulting cultivars exhibit a few sexual quirks. Ordinarily, a cherry blossom has only one pistil, the structure through which the pollen bores to reach the ovary in the base of the bud that eventually becomes a fat, juicy cherry. One bud, one pistil, one fruit is how it goes — on paper, at least. But a few of the sweet cherry varieties, including two popular fresh-market cultivars, Napoleon and Bing, occasionally freak out when the weather is hot at budding time and produce some flowers with two pistils. One bud, two pistils, two cherries jammed together. Sometimes the second fruit is undeveloped and remains a small dark nub near the base of the stem. Strictly speaking, these twinned fruits are considered unacceptable for market, but small-fruit harvesting and grading is a tedious job, and double cherries will find their way into the produce bin.
Another sexual quirk of cherry trees is their inability to pollinate themselves. Growers must plant a carefully planned pattern of two compatible varieties to make sure they have any fruit at all. No wonder those succulent little devils are so expensive by the time they get to us.