Domestically, the variety, to be sold under the brand name Cosmic Crisp, will be exclusive to Washington growers for at least the first 10 years, and though it’s grower friendly, it doesn’t come without a few challenges.
A highly vigorous, tip-bearing variety, its apical dominance can result in large caliper branches that present significant blind wood.
“Cosmic Crisp is not a forgiving variety. If you stub too short, wood will be blind forever. Leaving three fingers could be nothing,” said Stefano Musacchi, associate professor and endowed chair in tree fruit physiology and management at the Washington State University Tree Fruit Research and Extension Center in Wenatchee.
At Monson Orchards’ Lookout Ranch in Selah, Washington, orchard manager Jerry Mertz talked about steps he’s taken to try to avoid blind wood. The company has planted 120 acres of new, store-bought trees vertically, largely on Geneva 41 and Nic 29 rootstocks, with a smattering of Malling 935, all at 3-by-12 foot spacing. Another 50 acres has been grafted onto what was once a Red Delicious block, believed to be on M.106, with 8-by-14 foot spacing.
The latter is being trained a little differently; Mertz is running a V and running two leaders off each to try to fill the space. He plans to calculate the cost differential over time.
Mertz stubbed limbs that were growing well at 6 to 8 inches to avoid blind wood, and breaks are now growing well.
Musacchi liked the idea. “With a top graft, with two leaders or three leaders, within two years you recover your orchard. The vigor is really amazing,” he said.
However, Musacchi noted that growers are getting to the point they’re past talking about pruning trees; now, they want to talk more about management of the variety. “The industry is focused on growing trees as fast as they can to crop, but I’m scared because this variety can produce a lot of blind wood.”
Horticulturist Tom Auvil, formerly of the Washington Tree Fruit Research Commission and who is working with Mertz on the Monson plantings, advised growers not to worry about exceedingly vigorous or low-vigor trees. “Farm the 80 percent.”