哪种肥料最好?
A fertilizer bag has three numbers, indicating the percentages of nitrogen, phosphate and 钾肥. Nitrogen is the most important nutrient. Look for a fertilizer with at least 25% nitrogen. 如果可能的话, select a fertilizer that contains some slow-release nitrogen (sulfur-coated urea, 脲醛和IBDU). This will gradually feed the lawn this fall and next spring.
The second number, phosphate, is abundant in our soils and is rarely needed in established lawns.
第三个数字, 钾肥, will help our lawn to tolerate stresses, including drought and frigid winter temperatures. Most winterizer fertilizers contain 5–10% 钾肥.
Should I use a weed-and-feed fertilizer?
These fertilizers are okay at feeding lawns and okay at killing weeds, but not great at either. 原因如下:
糟糕的时间. The best times to feed a lawn (late May and early September) are not the best times to control weeds, namely crabgrass (late April) and broadleaf weeds (mid to late September).
对环境有害. Landscapes (including trees) grow better when herbicides are sprayed only where needed on lawns. Using weed-and-feed fertilizers puts toxic chemicals everywhere, even in areas with no weeds.
不好控制. Herbicides must be absorbed by weed leaves to work. Some small-leafed weeds such as clover and black medic cannot hold onto the granules and absorb the herbicide.
作为一种选择, spot sprays of liquid herbicide applied directly onto weedy areas can be applied to kill weeds at the most effective time and in a more effective manner.
还有其他建议吗??
Irrigate the lawn after applying (unless you use a weed-and-feed). This increases the effectiveness of the fertilizer, prevents the fertilizer from burning the grass, and reduces the likelihood that the fertilizer will runoff the soil during a rainstorm.
For a uniform distribution of the fertilizer, apply in two directions going at right angles to one another. 例如, apply half of the fertilizer going in north and south directions, and the other half going east and west directions.
Sweep up any fertilizer granules that are spilled on sidewalks or driveways to prevent polluting our streams and lakes.
