Irrigation is one of the main means to ensure timely and appropriate amounts of water required for lawn growth and development. It can be an effective measure to make up for the insufficient quantity and spatial unevenness of atmospheric precipitation. Sometimes sprinkler irrigation is also used to wash away chemical fertilizers, pesticides and dust attached to the lawn leaves, and to cool down in hot and dry weather.
1. The significance and function of lawn irrigation
(1) Irrigation is the material basis for ensuring the normal growth of lawn plants
Lawn plants consume a large amount of water during their growth. According to measurements, grass lawn plants consume 500-700g of water for every 1g of dry matter produced. Therefore, relying solely on atmospheric precipitation is far from enough. Especially in arid areas, areas with large evaporation and precipitation, water is the biggest limiting factor for lawn growth and development. The most effective way to solve a lawn’s lack of moisture is to irrigate.
(2) Lawn irrigation is one of the fundamental conditions to ensure the bright green color of lawn plants and extend their green period.
During the dry season, the leaves of lawn plants are small and thin, and the leaves turn yellow. The lawn will turn from yellow to green after sufficient watering.
(3) Lawn irrigation is one of the important links in regulating microclimate and changing temperature.
In hot climate conditions in summer, timely irrigation can reduce the temperature, increase humidity, and prevent high temperature burns. Carrying out winter irrigation before winter can increase the temperature and prevent freezing damage.
(4) Lawn irrigation is one of the conditions for enhancing the competitiveness of lawns and extending their useful life.
Lawn irrigation can increase the competitiveness of the lawn and suppress weeds, thereby extending its useful life.
(5) Timely irrigation of lawns can prevent pests, diseases, and rodent damage.
Timely lawn irrigation can prevent diseases, insect pests and rodent damage, and is one of the important means to ensure the normal growth of lawn plants. Some pests and diseases occur more frequently during the dry season, such as aphids and armyworms, which have a high incidence rate and serious harm during drought. Lawn pests can cause serious damage to lawns during the dry season. Timely irrigation can eliminate these diseases.
2. Determination of lawn water requirements
There are many factors that affect lawn water requirements. The main factors are grass species and varieties, soil types and environmental conditions. These factors usually interact with each other in complex ways. Under general maintenance conditions, lawns usually require 25-40mm of water per week, which can be met by rainfall, irrigation, or both. The amount of water required for irrigation varies in areas with different climate conditions. Plants generally only use 1% of the water they absorb. Growth and development.
(1) Evaporation
Evapotranspiration is a key factor in determining plant water demand. It refers to the total amount of water lost by a lawn per unit area in a unit time through plant transpiration and surface evaporation. In a lawn with large coverage, plant transpiration is the major part of water loss.
(2) Soil texture
Soil texture has an important impact on water movement, storage and availability. Sandy soils have large voids, so these coarse-textured soils drain well but have limited water holding capacity. Clay soils drain more slowly because they have a higher proportion of micro-voids than sand soils, while fine-textured soils hold more water because of their larger particle surface area and pore volume. Loam soil has moderate drainage and water storage.
(3) Climatic conditions
my country’s climate conditions are complex, and rainfall varies greatly from place to place, from a few hundred millimeters per year in the northwest to more than a thousand millimeters along the southeastern coast. The seasonal distribution of rainfall is also extremely unbalanced. Water consumption varies significantly from place to place, and measures must be adapted to local conditions. Determine reasonable irrigation water plans to make up for the uneven distribution of precipitation in time and space.
(4) Determine water demand
In the absence of conditions to measure evapotranspiration conditions, water consumption can be determined based on some empirical data. As a general rule, in the drier growing season, weekly irrigation should be 2.5-3.8cm to keep the lawn green and vibrant. In hot and arid areas, 5.1cm or more of water can be applied every week. Since the lawn root system is mainly distributed in the soil layer above 10-15cm, the soil layer should be moistened to 10-15cm after each irrigation.
3. Irrigation time
Experienced lawn managers often judge the watering time based on symptoms of water shortage in the lawn. The wilted grass turns blue-green or gray-green. If you can see footprints or tracks after walking or running a machine across the lawn, it means that the lawn is seriously short of water. When the grass begins to wilt, it loses its elasticity. This method is good for It is not suitable for lawns with high management level and high traffic flow, because the lawn is seriously short of water at this time, which has affected the quality of the lawn, and the lawn that is short of water cannot bear to be trampled.
Use a knife to examine the soil. If the soil at the 10-15cm lower limit of the lawn root distribution is dry, you should water it. The color of dry soil is lighter than that of wet soil.
The cheapest time of day to irrigate should be when there is no wind, high humidity, and low temperatures. This is mainly to reduce the loss of water evaporation. Conditions at night or early morning can meet the above requirements, and the water loss for irrigation is minimal. However, for irrigation at noon, 50% of the water can evaporate before reaching the ground. However, excessive humidity in the lawn canopy often leads to the occurrence of diseases. Nighttime irrigation will make the lawn grass wet for several hours or even longer. Under such conditions, the waxy layer and other protective layers on the surface of the lawn plants become thinner. Pathogens and microorganisms are easy to take advantage of and spread to plant tissues. Therefore, after comprehensive consideration, it is believed that early morning is the best time to install lawns.
4. Frequency of irrigation
Generally speaking, irrigate 1-2 times a week. If the soil has good water retention capacity and can store a lot of water in the root layer, the water requirement can be irrigated once a week. Sandy soil with poor water retention capacity should be irrigated 2 times, every 3 months. -Water half of weekly water requirement for 4 days.
Post time: Jul-01-2024