Agri Leader

Cool weather can harm crops, gardens

ANN M. O'PHELAN
Published: November 14, 2012

This summer was the third warmest summer on record for the lower 48. Earlier this month, a record-setting heat of 86 degrees was set in Tallahassee. Although we have experienced these warmer temperatures lately, we all know that the weather could change at the drop of a dime. And just a few years ago it did.

The sudden cold snap in December of 2010 was, in fact, one of the coldest on record in both Florida and Georgia. This quick and intense weather change cost Florida growers about $115 million.

While a cold snap can lead to devastation, even smaller temperatures that are a little below normal can cause concern for some growers and ranchers, even if it means they need to start making plans.

This year, NOAA is predicting below normal temperatures over the Florida peninsula, and an increased likelihood for above median precipitation across the central and eastern Gulf Coast region, so some preparations are in store.

In order to prepare, those in the ag business keep a watchful eye on FAWN, Florida's Automated Weather Network, fawn.ifas.ufl.edu. The network provides real-time weather agricultural weather information, along with climate tools, such as chill accumulation, and freeze alerts. They also stay updated through the National Oceanic and Atmospheric Administration, www.noaa.gov.

Additionally, their equipment such as irrigation pumps and heaters — for barns, animal confinements, greenhouses and orchards — are checked to ensure they are all in good working order. Adequate stocks of hay, straw, blankets, agricultural cloths and other insulating materials are inventoried to make sure there are plenty of supplies on hand. Furthermore, an ample food supply needs to be readily available for animals that have extra needs during the colder weather months.

"Any time the temperature drops below a certain level and frost, cold winds, or freezing temps are hitting us, damage can quickly be done," said Lisa Lochridge, of the Florida Fruit and Vegetable Association, who explained that the types of crops grown makes a difference in how preparing for and protecting from the cold is handled.

"Strawberry and blueberry growers run irrigation systems as the water coats the plants, and the freezing layer of ice works to protect them," said Lochridge, who explained that growers sometimes harvest early to save what they can.

Citrus growers also use low-volume drip irrigation around the roots, because the water creates heat. Sod farmers use irrigation as well. If freezing temperatures are predicted, the sod is irrigated with just enough water to moisten the soil without saturating it.

Agricultural cloths, row covers, blankets or organic materials are brought out to the fields in order to protect crops from the cold, whereas tropical fish are brought indoors. Heaters are sometimes used in orchards. In the southern part of the state, helicopters are occasionally flown over crops, like corn and green beans, in order to push the warm air downward. Intervention is often needed to help save crops from incurring cosmetic damage, dying to the ground or dying off.

For farm animals like dairy cows, it's important to keep them warm with barn heaters and other materials. Dairy cows struggle with many issues when it comes to cold snaps, as they do not like cold temperatures and winds. The cold can adversely affect milk production. They do not eat as much and this can cause severe stomach upset.

"These digestive upsets are called "displaced abomasums (DA)," as one of their four stomachs stop functioning normally due to a result of the temperatures dropping and strong wind speeds," said Joe Wright of V& W Farms in Highland County, who explained that the affected cows must then be treated.

Also concerning is that frosts can turn pastures brown and take nutrition out of whatever grass is left in the pastures. For replacement, farmers must use hay or have planted annual winter grasses such as ryegrass.

The calves, especially, need to be kept warm.

"Dairy farmers often use hay or straw for bedding material in calf pens or paddocks, so that the calves have something to bed down in and essentially make little nests," said Wright, who explained that the material also helps insulate and block the wind.

Of course, if the winter months stay on the cool side without the damaging extremes, well, that's a different outlook.

"Dairy cows actually like the cooler weather we are having," said Wright, who explained that when temperatures range from 45 to 70 degrees, the cows actually eat more feed and convert those calories into more milk. Plus, they have fewer health problems.

Certain crops, such as peach trees, rely on a bit of the cooler weather in order to bloom as they have a specific amount of chilling requirements. A variety of cool season vegetables, such as cabbage, lettuce, carrots and kale offer better flavor and texture when grown during the winter months. Of course, farmers, growers and ranchers also appreciate a bit of relief from the heat while they're hard at work.

Nevertheless, when it comes to the winter months, it's better to hope to for the best and plan for the worst.