click image to zoomCourtesy University of FloridaVance Whitaker leads the University of Florida’s strawberry breeding program that has recently released the new varieties Sensation and Winterstar.Florida strawberry growers are looking to two new varieties to wow consumers.
Winterstar, in its second year of commercial production, and Florida Sensation, expected to be commercially available next year, are both products of the University of Florida’s breeding program.
While both varieties have similarities to Florida Radiance and Strawberry Festival, the state’s dominant strawberry cultivars—including Radiance’s susceptibility to phytophthora fruit rots—they also hold new advantages, says Vance Whitaker, assistant professor of horticulture at the Gulf Coast Research and Education Center in Wimauma. Whitaker heads the strawberry breeding program.
Sensation so far looks to be a true star, he and growers who’ve participated in field trials say.
It consistently produces large fruit with flavor that tasting panels score “right at the top,” Whitaker says.
“Sensation has such good fruit quality that it will separate Florida berries from anything else in the store,” says Joel Connell, general manager at Grimes Farms in Plant City. “It eats so well I feel people will return looking for it.”
Winterstar brings its own pluses, Whitaker says. It not only produces firm berries, but they also offer a different flavor profile: milder and sweeter, thanks to slightly lower acid levels.
Preliminary trials suggest that Sensation can be planted at earlier dates than Radiance, allowing growers to hit a potentially more profitable marketing window as well as to stagger their overall plantings for a longer sales season, he says.
He warns against planting too early, though, especially for growers in Georgia, North Carolina and South Carolina who have adopted other Florida varieties. Further trials will help pinpoint the best timing for planting.
For growers in areas that undergo cooler winter temperatures than the Plant City area, “You want to make
sure you plant [Winterstar] early enough and fertilize through drip [systems) at sufficient rates to make a good solid plant,” he says. “Because it’s a more compact plant you need to get a good crown set before winter.”
Modifying cultural practices
Bielinski Santos, associate professor of horticulture at the Gulf Coast research center, has participated in the trials of both Winterstar and Sensation, comparing them to Festival.
Festival produces bigger plants with deeper root systems that better tolerate drought and stress, he says.
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.
Harvest workers can pick both varieties faster than Festival and Radiance, thanks to plants and leaves that grow more upright and expose rather than hide fruit. That’s particularly helpful when growers face labor shortages.
“We’re trying to get away from varieties that tend to bog down workers in the field,” he says.
Winterstar’s inconsistent fruit size does make it a little more difficult to harvest, says Connell of Grimes Farms.
Consistent size, with minimal culls and a steady rate of maturity, is the key to picking efficiency, Whitaker says.
This season, Connell’s third working with Winterstar, will be his first in commercial quantities. He’s had two years’ experience with Sensation.
“We’re very excited about [Sensation],” he says. “It’s a plus on just about everything we look for.”
Both Connell and Young foresee declines in Festival and Radiance acreage as these two new varieties get more exposure.
But Sensation’s tendency to produce better quality may catapult it ahead of even Winterstar, Young says.