As the crop’s health benefits are touted and prices for it rise, blueberry acreage is expanding in Florida.

“The numbers we have now aren’t exact, but there are more than 3,000 acres in the state,” says Dr. Bielinski Santos. “Only a few years ago, there were about 1,000 acres.”

There are several factors for the increasing acreage, says the small fruit and vegetable horticulturist at the University of Florida’s Gulf Coast Research and Education Center in Wimauma. A main reason for the blueberry bump -- alongside friendly soils and weather for the crop -- is a unique marketing window that growers can take advantage of.

Unique window

“None of the blueberries from other parts of the country are being harvested when Florida’s are produced. We usually harvest the bulk of our crop in March and April, and our growers are provided a very good certainty of a strong market and prices. We usually don’t do ‘evergreening.’ We just try to hit the market window.”

The majority of Florida blueberries – “approximately 66 percent” – are grown in the north-central region. The balance is grown farther south on the Gulf Coast, “near Tampa, and other areas of west-central Florida.”

Varieties have been adapted to fit the state’s different blueberry-growing environments. In north Florida the varieties are “relatively high-chill, while in west-central Florida we require varieties in the low-chill range. The University of Florida has a very active breeding program to provide varieties for every region.”

Part of Santos’ job is to study varietal performance but he also looks “at production practices like fertilization and irrigation to improve performance and profitability of the crop for the growers.”

Florida producers grow both rabbiteye and highbush blueberries. The type “depends on what part of the peninsula you’re on. However, highbush is a main contributor of the crop.”

Another plus for Florida’s blueberry crop is also tied to its harvest date. “This doesn’t apply to every operation but some of state’s strawberry growers also have blueberries. Growers want to keep labor working.”

Strawberries are usually harvested up to the first week in March – exactly the point when blueberry harvest begins. “That provides a continuous period of work for the farm labor.”

Cropping practices

Asked about blueberry cropping practices, Santos says there’s a variety “and that’s one of the challenges of my job. I must come up with practices that address different regions and types of growers.

“If you ask growers in this state ‘what’s your irrigation program?’ everyone will provide a different answer. Some growers have two high-quality drip tapes per bed. They’ll water 10 minutes on, 10 minutes off. Other growers water only when they feel it is necessary – no set schedule. Others water twice daily, others every three days, others use sprinkler irrigation.”

One of Santos’ projects is “to analyze, through science, the most appropriate procedures for the best use of water. That also involves watching the leaching of nutrients into underlying sand.”

A standard practice is to utilize pine bark, either on beds or in a trench where the plant is grown. “That’s helps maintain the pH the plants need. Every year or two, you need to check that the pH levels are low enough to ensure the blueberries are in an optimum environment for plant development.”

As with irrigation, fertilization practices are variable. “Some use dry fertilizer and apply it up to seven times during the season – anywhere from 200 to 500 pounds of nitrogen. Other growers apply fertilizer through the drip tape (fertigation).

“I don’t want to say one fertilization method is better than another. Whatever a grower uses, he must manage it properly.”

One of the things growers must take into account is the link between fertilizing and pruning a crop properly and in a timely manner. “If you do that in the right way, the plant will use the fertilizer when appropriate.”

Santos doesn’t work on blueberry pest management. “My understanding is that there isn’t a main pest that sends up red flags where you say ‘Oh, that’s a threat across the state.’ Pests are manageable, right now.”

Florida blueberry plants normally lose their leaves by November. That’s especially true in the northern latitudes. If that doesn’t happen in the warmer south, growers apply a chemical that induces the plant to dormancy.

In terms of planting, there’s a wide variety of methods – “although not as wide as with the fertilization. Usually growers work with 1,000 to 1,500 plants per acre. The distance between the plants depends on the variety, the equipment on hand and the practices they utilize.”

Potash project

Santos recently began a potash project aimed at blueberries.

“I’ve got a graduate student working on it. This is the first year of the three-year study. We’re trying to devise two ways to compare sulfate of potash (SOP) with muriate of potash (MOP), which is extensively used by growers who apply dry fertilizer. We think sulfate of potash might have a niche in the market.”

First, Santos and colleagues want to know the crop’s efficiency in absorbing the SOP in comparison with MOP. Also, what is the added effect of sulfur on the land?

“Right now, in all the vegetable crops – particularly in tomatoes and peppers -- we have found significant response to sulfur in the soil. We want to see if blueberries have a similar response to SOP.”