October 2007

Protect Your Greenhouse By Jasmina Dolce

As hurricane season comes to an end, you may be feeling quite relieved that this year was much more calm than past years. One of the biggest challenges growers face is the unpredictable weather. In 1992, plenty of growers were unprepared for one of the most destructive hurricanes in U.S. history, Hurricane Andrew. And in 2005, no one predicted the damage Hurricane Katrina caused. So it's pretty safe to say you can never be too cautious when it comes to preparing for inclement weather.

And even when you prepare for the worst, you might luck out. This year is a perfect example. In May, the National Oceanic and Atmospheric Administration (NOAA) predicted an active 2007 Atlantic hurricane season because of warmer ocean waters. The administration warned that as many as 17 tropical storms could occur, with 7-10 developing into hurricanes. According to the NOAA, the average Atlantic hurricane season sees about 11 tropical storms with only two major hurricanes. This year has actually seen very few tropical storms. Luckily, none caused too much damage, and no severe hurricanes hit the United States.

Some growers are still feeling the aftermath of recent tropical storms and hurricanes. Bill Lyden, Farm Life Nursery, Homestead, Fla., is still recovering from the damage left behind by various storms. His business was first hit in 1992 when Hurricane Andrew, a Category 5 storm, wiped out most of southern Florida and other parts of the Southeast. Until then, he never really thought his business would be affected by hurricanes. "Even though it was such a big storm, and there was plenty of warning, I just never thought about leaving town or looking at it as a life-threatening event," he says. This was the turning point for Lyden, as well as many other greenhouse growers.

Prepare for the Worst, Hope for the Best

Although Hurricane Katrina severely damaged parts of the Gulf Coast region, it was only a Category 1 hurricane when it first hit Florida. Many business operators and residents did not expect the amount of damage that occurred. Two months later, Hurricane Wilma came through and added to the devastation.

"Anything that was left after Hurricane Katrina was lost in Wilma," Lyden says. "All of our structures were destroyed, as well as all of the plant material." The lesson many growers took from the 2005 storm season was that you can never underestimate a hurricane. The moment one storm exits, another may surprise you. These storms may not have been as serious as others in the past, but the fact that they were back-to-back only intensified the consequences, creating nearly the same amount of damage as Hurricane Andrew 13 years prior.

It also is impossible to guess which areas will be affected by hurricanes and storms. "If you look at a 50-year map of where the different hurricanes [originated], there is really no safe place in Florida," says Gary Hennen, Oglesby Plants International, Altha, Fla., a greenhouse operator in Florida's panhandle. "The lines go all over the place. It's very unpredictable."

Invest in Your Structure

A greenhouse structure may be the largest financial investment for a grower, but it is also by far the most important. "The key to the business is not to lose your structure," Lyden says. "If you lose your structure, you're going to lose your plants." After the 2005 hurricanes, Lyden was forced to make the difficult decision to rebuild his entire operation. After suffering such a tremendous loss, he knew a successful rebuilding would require drastic changes. His goal was to increase his odds of survival.

Unlike Lyden, Gary Hennen's business has never been significantly affected by hurricanes, but that doesn't stop him from preparing for the worst. "Our structures that we build are engineered to withstand about 120-mile-per-hour winds," he says. "That is probably the only thing that I insist on doing at this point: getting a strong structure put up."

It has been two years since Lyden put up brand-new, retractable-roof greenhouses, and he hasn't seen any major storms since then. "We really have not been tested, and it's fine with me if we are never tested," he says. The new structures were quite an investment, but Lyden knows they will give his business a better chance at survival the next time a hurricane occurs.

Hurricane Preparation Guidelines

The University of Florida, IFAS Extension Web site provides a hurricane preparedness list for nurseries. Here are some guidelines that will help you prepare your business — even months in advance — for hurricane season. Keep in mind that this is not a full list. Visit edis.ifas.ufl.edu/EP076 for in-depth guidelines.

Six months pre-hurricane:

1. Construct buildings according to codes and regulations for hurricane wind loads.
2. Schedule maintenance for equipment used during hurricanes, such as adding stabilizers to generator fuel.
3. Obtain crop insurance; otherwise, federal loan assistance will not be available.
4. Develop a written plan of pre- and post- hurricane responsibilities and job descrip- tions for personnel.

Two to six months pre-hurricane:

1. Clean ditches and grade areas for drainage.
2. Prune permanent trees to reduce wind resistance.
3. Provide for portable water storage.
4. Tie down portable buildings.

One to two days pre-hurricane:

1. Irrigate plants and remove water from reservoirs.
2. Remove plants from benches.
3. Fill fuel tanks and fill sprayers with water.
4. Print out payroll, plant inventory, fertilizer and pesticide inventory.

Within one day pre-hurricane:

1. Secure items such as small portable trailers and substrate mixing equipment; position portable generators.
2. Dismantle irrigation risers; remove greenhouse plastic and shade cloth.
3. Place tractors in fields.
4. Turn off natural and propane gas, water and electricity.

SIDEBAR

Watch Out for La Ni–a

Although hurricane season is coming to a close, destructive weather can still strike when you least expect it. A La Ni–a watch has recently been issued by the Southeast Climate Consortium and state climatologists of Alabama, Florida and Georgia. According to the consortium, the tropical Pacific Ocean is on the verge of slipping into a full-fledged La Ni–a. Chances are strong that La Ni–a conditions will develop, strengthen and persist through the fall and winter months.

Under La Ni–a conditions, sea surface temperatures along the equator in the eastern and central Pacific Ocean are cooler than normal for at least five months. These conditions usually bring a warmer, drier cool season to Florida, central and lower Alabama, and central and south Georgia. Growers who do not have irrigation capability have a high risk of being affected by winter drought.

The Southeast Climate Consortium also estimated the probability of normal or above rainfall for January was 8 percent for central Florida. For the panhandle of Florida, south Georgia and lower Alabama, the probability of normal or above rainfall in January is 20 percent; the probability of moderately dry conditions is 50 percent and 30 percent for very dry conditions. Growers should remain on the lookout for future weather forecasts because they can change at any moment. Remember, preparation is key.

Hurricane Info on the Web

Here is a list of some Web sites you can visit for more information on hurricanes and preparation:

American Red Cross — Hurricanes:
www.redcross.org/services/ prepare/0,1082,0_253_,00.html

Florida Hurricane Reports:
iwin.nws.noaa.gov/iwin/fl/hurricane.html

Hurricane and Storm Tracking:
hurricane.terrapin.com

Hurricane and Natural Disaster Brochures:
www.aoml.noaa.gov/general/lib/ hurricbro.html

National Hurricane Center:
www.nhc.noaa.gov

National Weather Service:
www.nws.noaa.gov