Hot in the Garden: Too Much Sun Can Harm Vegetables
小编摘要：并不是所有植物都需要那么多阳光的 ，物极必反，过多的阳光对部分植物、蔬菜的生长是有害的。当气温超过32摄氏度时，植物的生长会受到一定的伤害 。
Last week we discussed how to growvegetables in partial sun. This week we learn how to protect vegetables from too much sun.
Curtis Swift is an extension agent at Colorado State University. He says shading plants from intense sunlight in hot weather can increase production. Plants can suffer damage when their temperature rises above thirty-two degrees Celsius.
CURTIS SWIFT: "Tomatoes, peppers,eggplants, and okra and other members of that family drop flower buds and young fruit when the plant temperatures exceed thirty-two degrees C."
Plants can get sunburn. Yellow spots mayappear on their leaves and fruit. These areas can become thin and white as plant tissue is affected.
Curtis Swift says shade can help correctthese problems.
CURTIS SWIFT: "What it does is, it actually allows the plant to give off adequate water, which cools thetissue."
He suggests shading plants with bed sheets,shade cloth or brush -- in other words, sticks and branches. Cut them about a meter long and stand them in the ground on the south and west sides of plants.
CURTIS SWIFT: "Anything you can putover the plant. A lot of people can cut brush at the edge of the field and stick that into the soil on the south and west side of the plant and provide some shade."
Curtis Swift says if you use clothsheeting, suspend it at least five centimeters above the plants. That way there is enough space for bees to fly around. Be careful not to cover plants too closely,which could trap heat and defeat the purpose of shading.
People can also buy canopies to sheltertheir plants. Some canopies have narrow strips of metal or wood to provide either sunlight or shade, depending on the position of the sun.
Curtis Swift says shading works with fieldcrops as well as vine crops like squash. People sometimes plant shrubs or trees to shade their vegetables. But he says tree roots compete with the vegetableroots. The veggies may not get enough nutrients and water.
And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. Here are a few of your comments about last week's report on shade growing. Ko from South Korea wrote: I can't imagine plants in the shade for most of day without sunshine! That's a really creative idea.
Andy in Chile wrote: This is an interesting article. But you forget that the shadow allows the growth of the fungi. And Slava in Croatia recalled: Once I grew small tomatoes on a balcony under a roof. Sun shone there only in the afternoon. In October the plants had only afew green tomatoes. I took them inside behind the window and they had ripe fruits on Christmas and the entire winter.