The rationality and effectiveness of lawn fertilization are determined by many factors, including the type and nature of fertilizer, the growth characteristics of lawn grass, growth period, climate, soil and other ecological factors, as well as various management measures.
Nutrient supply and demand
Nutrient supply and demand is the basis for judging whether the lawn needs fertilization and the type of fertilizer required. It mainly refers to the demand for nutrients of lawn grass and the level of soil fertility. The nutritional status of lawn grass can be determined through plant nutrition diagnosis and tissue measurement, and the soil fertilizer supply capacity can be determined through soil testing. Combining the two can determine the nutrient supply and demand of lawn grass, so as to apply fertilizer in a targeted manner.
Plant diagnosis is a very important technology, especially in the application of nitrogen fertilizer. The type of nutrients required by lawn grass can be determined based on the symptoms of deficiency, but it is important to exclude other possibilities, such as waterlogging and temperature. Tissue testing can directly determine the amount of nutrients actually absorbed and converted by lawn grass, which is especially important for trace elements.
Soil testing can fully understand the fertility of lawn soil, so as to determine the nutrient composition, proportion and application amount of fertilizer. In order to reduce costs, when applying base fertilizer, the amount of phosphorus and potassium fertilizer is mainly implemented according to the results of soil testing. Soil testing should also be carried out regularly during the maintenance of mature lawns, and the fertilizer application plan should be gradually improved.
Characteristics of lawn grass demand for nutrients
Different lawn grass species have great differences in their demand for nutrients, especially for nitrogen. Relatively speaking, among cool-season lawn grasses, red fescue has low requirements for nitrogen, and lawn density and quality decrease under high nitrogen conditions. However, meadow fescue requires fertile soil and cannot form good turf on poor soil. Although tall fescue tolerates extensive management, it responds significantly to nitrogen fertilizer. Among warm-season lawn grasses, false centipede grass, carpet grass and coastal paspalum have low requirements for fertility, and bermudagrass has high requirements for nitrogen fertilizer. Zoysia performs better under high fertilizer conditions, but can also tolerate low fertilizer.
There are also differences in the demand for nutrients between different varieties of the same species. For example, the bermudagrass variety Texture10 requires more fertilizer than Ormand, while the meadow grass varieties Midnight and Glade require more fertilizer than Kenblue and Park. Varieties that require more fertilizer must have sufficient fertilizer supply, otherwise the quality of the lawn will decline. For varieties that require less fertilizer, excessive fertilization will not only fail to improve the quality of the lawn, but will reduce the quality of the lawn and increase management costs.
The demand for nutrients is also different in different growth periods of lawn grass. When the lawn is planted, the base fertilizer must contain 5 grams/square meter of pure nitrogen, while phosphorus, potassium, etc. can be determined based on the results of soil tests to determine whether to apply and how much to apply. On mature lawns, fertilization during the vigorous growth period is mainly nitrogen fertilizer, and phosphorus fertilizer can be omitted. In unfavorable growing seasons, less nitrogen fertilizer should be applied, and more phosphorus and potassium fertilizers should be applied appropriately. In order to maintain the existing high-quality lawn, a lower nitrogen supply level can be selected. However, in order to promote the growth of lawn grass and improve the lawn grass with low density, weak growth or due to environmental stress, pests and diseases as soon as possible, a higher nitrogen level is required.
The impact of the environment on plant absorption of nutrients
When environmental conditions are suitable for the rapid growth of lawn grass, there must be sufficient nutrient supply to meet its growth needs. At this time, sufficient nitrogen, phosphorus and potassium supply is very necessary for the plant’s drought resistance, cold resistance and stress resistance. However, before or during the stress, the application of fertilizers should be controlled or applied with caution. When the environmental stress is removed, a certain nutrient supply should be guaranteed to facilitate the rapid recovery of the damaged lawn grass. For example, the application of nitrogen fertilizer to cold-season lawns before the arrival of high temperatures in summer should be quite careful. Nitrogen promotes the growth of lawn grass and increases tissue water content, but reduces the stress and disease resistance to high temperature and drought. Excessive nitrogen fertilizer use in summer is often accompanied by serious lawn diseases.
The texture and structure of the soil have a great influence on the ability to retain the applied nutrients, and also directly affect the application of fertilizers. Coarse-grained sandy soils have poor fertilizer retention and are easily lost through leakage. When fertilizing, small amounts and multiple times or slow-release fertilizers should be used to improve fertilizer utilization efficiency.
Lawn use and maintenance intensity
Different lawn uses have different maintenance intensities and fertilizer requirements. The quality requirements of golf green lawns are the highest among all lawns, which determines that their maintenance intensity is also the highest. Due to the high intensity of use of sports field lawns, attention should be paid to fertilization to promote the recovery of lawn grass. For soil and water conservation lawns, their quality requirements are low, and only one fertilizer is needed per year, or even no fertilizer is needed.
Lawn management measures
Among various lawn management measures, mowing and fertilization are most closely related. For the sake of beauty, people often remove the clippings, and at the same time take away a lot of nutrients. If fertilization is not increased, the leaf color of the lawn will become lighter, resulting in a decrease in lawn quality. It is reported that returning grass clippings can reduce the amount of fertilizer by 30%. For Moerion meadow bluegrass lawns with grass clippings removed, the nitrogen demand should increase by 0.9 to 1.5 grams per square meter per month during the lawn growing season. Lawn irrigation also affects fertilization. Frequent irrigation will increase the leaching of lawn nutrients, thereby increasing the lawn’s demand for fertilizer.
Post time: Nov-13-2024