Growers who try Winterstar and Sensation should provide young plants with a little more nurturing, because they’re not as forgiving as Festival.
But to balance that, both of the new varieties seem to produce the same yields with less fertilizer. For instance, Festival might need 1.5 pounds of nitrogen per acre per day, while Winterstar could get by with between 0.75 and 1 pound per acre per day, Santos says. The amount needed varies through the growing season.
“Once established, they produce well,” he says. Their shallower root systems may require adjusting irrigation schedules and systems, but whether that means more water overall or applying the same amount at more frequent intervals will require additional tests, Santos says.
He also is looking at how they grow in high tunnels for use in other production regions.
In addition to susceptibility to phytophthora, both Winterstar and Sensation also are sensitive to botrytis, says Natalia Peres, associate professor of plant pathology at the Gulf Coast center.
But they both show better resistance to anthracnose than Festival, and also are more resistant to charcoal rot, a new disease coming into prominence with the phaseout of methyl bromide, Peres says.
“Growers tell us as long as they know what to be worried about; they’re OK [with some disease susceptibilities] because they can’t get resistance to everything,” she says.
Disease concerns do make strong resistance management programs even more important, Peres says. Many of the fungicides available to control botrytis are showing signs of developing resistance.
“We advise growers to use the forecast system and to spray only when they need to,” she says. Peres has developed the online Strawberry Advisory System to predict conditions favorable to fungal diseases.
Upright growth benefits harvest
Every variety has pluses and minuses to consider, says Ronnie Young, owner of Three Star Farms in Dover. “None of them are perfect.”
Young is in his second year growing Winterstar in significant numbers and has tried small amounts of Sensation in a test plot. He’s had to adjust his nutritional program slightly for Winterstar and has noticed a tendency to susceptibility to two-spotted spider mites.
Winterstar offers a good fruit shape, and while it can produce small berries, the fruit packs and ships well.
Sensation is a steady producer, and it produces large berries more consistently, Young says.