Frequent frosts and freezes
Harsh winters have killed millions of trees in Poland.
In Poland's main apple-growing region, south of Warsaw, frosts and freezes are a fact of life, according to Dr. Augustyn Mika, professor at the Research Institute of Pomology and Floriculture in Skierniewice.
The apple growing region around Grójec is dry with annual rainfall of 500 millimeters (20 inches). Evaporation is also low because of cool temperatures. The soils are poor and the winters can be severe, as cold air moves in from Russia to the east.
The area had six major freezes during the last century. Each time, about a third of the trees were lost and another third were badly injured, Mika told members of the International Fruit Tree Association when they visited the Skierniewice Institute. Four years ago, many trees were damaged when temperatures plunged to between –35 and –78°C (–31 to –104°F).
Growers can expect spring frost damage every third year, Mika said. Two years ago, there was major damage to flower buds so the crop was down, but last year the trees came back with a record crop of 2.8 million tons.
Mika said the country's best, though smaller, fruit-growing regions are Silesia, in the southwest, and the southeastern part of the country, where the soils are better, the temperatures warmer, and the rainfall higher.
"We don't produce fruit on the best sites," he said. "We produce fruits in areas that are good for selling."
In the past, fruit was transported by boat. Poland's longest river, the Vistula, runs through the main apple-growing region and empties into the Baltic Sea to the north. Although transportation by boat is no longer important, most of the fruit is still grown in that region.
Poland is Europe's supplier of cheap apples. About 44 percent of fresh and processed fruit goes to neighboring Germany. After Poland joined the European Union in 2004, its growers could sell their fruit freely all over Europe. However, grower Krzysztof Hermanowicz said that they were not prepared at the time to meet the standards demanded by Western European buyers. "Very few farmers could go and sell apples directly to Germany, to France, to England, or any other European country."
Joining the European Union also impacted their costs, raising the prices of inputs such as pesticides and fertilizers. "From one hand it was good; from another not good," he said.
However, Poland has a strong apple industry, which continues to grow, with 10 million trees planted each year, Hermanowicz said.
In addition to being one of the world's largest apple producers, Poland produces 66,000 tons of pears, 101,000 tons of plums, 59,000 tons of sweet cherries, and 197,000 tons of sour cherries annually.
The main pear varieties are Conference, Lucas, and Clapp's Favorite, Mika said. "We have not good conditions to grow pears, because it's too cool, and all the pear breeding was done in France, Germany, and Belgium, in warm conditions."
Growers have tried to grow pears on semidwarfing quince rootstocks, but have had problems with viruses that lead to pear decline, he said. Fireblight is difficult to control, and the main insect pest is pear psylla.