Peaches
Peaches (Prunus persica) originated in China and were domesticated in the Yangtze River Valley about 8,000 years ago. China remains the largest producer of peaches, producing about half of the peaches in the world. They spread from China to Japan by 4,700 BCE, and westward to Greece by 300 BCE.
Today, peaches are grown throughout temperate climates in the world and even in tropical highlands where there is enough cool weather to satisfy their chilling requirements (peaches require cold weather to subsequently bloom).
In the United States, California is the largest peach producer in the United States by a long shot. Washington produces only about 2% of what California does, and peach production is much lower than that of other orchard crops, namely apples and cherries.
In the Pacific Northwest
The climate that peaches grew in originally is a humid subtropical one, with warm, humid summers and dry, cool winters.
The main issues that arise with peach production on the Northwest Coast can be traced back to this fact; peaches want both more heat in summer and drier conditions in winter than the region offers. They bloom in early spring, which is less suitable for pollination due to rain, and are highly susceptible to peach leaf curl, a fungal infection caused by Taphina deformans. The disease requires constant treatment of the trees to prevent, and unfortunately, leaf-curl resistant varieties still don’t seem to do very well against the fungus. In my experience, peaches I’ve eaten from the Willamette Valley area were of much poorer quality than those grown further east. Anecdotally, as well, growing the trees is a major hassle, and many trees eventually succumb to disease.
These issues with growing peaches in the Northwest Coast are why they are best suited to the central parts of the Pacific Northwest, the Columbia Plateau in particular, and the Sacramento Valley region.
The lower precipitation of these areas reduces the dangers of peach leaf curl, and the greater amounts of sunshine help develop sweet fruit. The caveat, however, is that because they are originally from a climate with plentiful rain in summer, peach trees require more irrigation than other orchard trees. It stands to reason that peach orchards are usually located near rivers, for example near Mount Hood, where orchards are in close proximity to the Columbia River.
Although peaches will likely remain a lesser crop in our region, the fruit grown in Columbia Plateau is of excellent quality and can get to market quickly enough to maintain that quality even though they are a highly perishable fruit.
Species and varieties
Peaches
Cultivated peach (Prunus persica)
Yellow or white peaches
Freestone or clingstone peaches
Flat peaches
Nectarines
Peach varieties
Peaches have either yellow or white flesh. Yellow peaches are usually tarter and firmer than the sweeter white peaches.
As with plums and apricots, peaches also come in freestone and clingstone varieties. The names are fairly self-explanatory - the fruit clings to the stone (pit) in clingstone varieties, and it separates easily in freestone varieties. There are intermediate varieties as well.
Flat peaches, which are donut-shaped, are usually white-fleshed varieties. Known as a “pan-tao” in China, where they originate from and are known from at least the 12th century.
Nectarines are the same species as peaches, the only difference being that they exhibit the recessive trait of smooth skin rather than the fuzzy skin found on most peaches.
Wild peaches
In addition to the common peach, there are six wild peach species, mostly of interest for their use as rootstocks for Prunus persica. They are unlikely to be of much culinary use in our region, as they generally produce edible, but undesirable fruit, though they may have traditional uses in their local cuisines. The species are all from China or Central Asia.
Cooking with peaches
Peaches are available mid- to late-summer in the Pacific Northwest.
Removed from the inside of the peach stone, peach kernels can be used to make persipan, a product which is similar but cheaper than marzipan. The kernels are also used to make “almond” extracts and flavorings, or can even be processed into oil for culinary or cosmetic purposes.
The petals of peach flowers, available in spring, are edible, but light on flavor. They’re mainly useful as a garnish. Make sure to use only the petals as the other parts of the flowers can be bitter.
