In early spring (mid-February to mid-March - depending on the region), there is still enough winter moisture and precipitation available, so that the fertilizer grains can be easily dissolved and the nutrients can be quickly absorbed via the roots.
Grass roots are already very active at this point and eagerly absorb nitrogen and the like. They have a lower temperature optimum than leaves or shoots. Nitrogen fertilization, especially with the nitrogen forms ammonium and nitrate, which are directly available to plants and can be absorbed immediately, therefore hardly results in leaf growth at this point in spring. Nevertheless, after a few days, the change in color of the leaves becomes visible. The wintry yellow gives way to a fresh, strong green. This color change cause by the nitrogen (N) and shows a significant increase in the chlorophyll content in the grass leaf. The daylight intensity decreases during late autumn and winter. As a result, the grass plant breaks down chlorophyll because it needs the nitrogen, among other things, for storage as frost protection in the cell vacuoles to protect the cells from freezing.
In spring, as the sun rises, sugar - the product of photosynthesis - becomes again more important for the plant and thus does chlorophyll. However, the breakthrough in spring comes with the first nitrogen application with available nitrogen forms.
Fresh, already active roots absorb the nutrients immediately and the grasses synthesize large quantities of chlorophyll. This increases the photosynthetic output considerably and thus more sugar is available for growth. First, more roots are formed - the basis for a stress-resistant, vital and drought-tolerant lawn. With rising temperatures, new, proper and large leaves with a lot of photosynthetic surface follow. This leads to a further increase in the supply of sugar in the plants and ultimately results in the formation of new shoots.
As a result, the thickening sward displace areas of disease, weeds or mosses, gaps and winter damages are closed.
Vital, stress-resistant lawn scars in early spring are the key to a good lawn year. Once in shape, you are ready to go on dense, healthy, beautiful lawns.