Dress cooler. That's great advice in Deep South summers, for people and plants alike. And a new pot allows nursery growers to do just that for their plants.
"These are actually containers made out of recycled newspaper for growing nursery plants," said John Ruter, a University of Georgia nursery crop researcher at the Coastal Plain Experiment Station in Tifton, Ga.
"Plants in these containers stay a good 15 to 20 degrees cooler in the root zone," he said. "If you have a better root system, you get a better top and better plant all the way around."
Georgia nursery growers put their plants in black plastic pots. But they lose as many as half of some varieties in July, August and September. That's when temperatures soar and frequent rains keep the plant roots too wet.
Ruter, a horticulturist in the UGA College of Agricultural and Environmental Sciences, is studying the new beige, recycled-paper pots and is learning how various plants respond to them.
The pots offer many advantages, he said. The porous fibers absorb only a part of the heat from sunlight and allow excess water to escape. The pot creates its own evaporative cooling system, much like sweating in humans.
Black plastic pots absorb solar energy, heating the soil to temperatures that can kill tender young roots. The plastic also prevents water evaporation from the sides of the pot, making root rot more likely.
Don't look for the newspaper pots in your garden center. So far, they're only available wholesale. But they can still help home gardeners.
"The advantage to the consumer," Ruter said, "is that they get a plant that's generally going to be bigger and have a better root system. It's going to transplant into the landscape better and perform better."
In 1996, Georgians bought more than $273 million in living plants. That's up by more than a third over 1995 sales. Georgia products include greenhouse plants, turf grasses, ball-and-burlap and bare-root trees, bushes and shrubs. Nearly all these plants get their start in a pot.
To make the new pots, processors press recycled paper pulp into a mold that looks much like a standard nursery pot. The fiber pots cost about twice as much as the plastic. And so far, growers have been slow to use them.
But Ruter figures most nurseries can easily recoup the extra expense in the higher survival rates of many plants.
Some plants' survival rates don't improve enough to warrant the higher cost. But many do. With one holly, for instance, growers can expect only 5 percent losses in black plastic pots. But with another variety, losses of 30 percent to 50 percent are common.
In the South, the fiber pots disintegrate in about six weeks. But when they're treated with a copper mixture Ruter is studying, they can last up to two years in a nursery or greenhouse.
If the new pots catch on, they're simple to dispose of when you take your plant home. "Take the fiber container off, crush it up and toss it in the bottom of the planting hole," Ruter said. "Mother Nature and microbes in the soil will break down the fiber container.
"It's a good way of taking a waste product -- old newspapers -- and turning it into something useful," he said.