Detailed Explanation of Lawn Planting Methods and Technical Key Points

Lawns hold an important place in urban greening, providing a green backdrop for scenery and offering certain ecological functions.

1 Preparation before planting

Select suitable grass species for planting according to the site conditions. Deeply plow and level the planting site, and apply 1000kg of decomposed farmyard manure, 200kg of plant ash and 500kg of river sand per 667m2 to improve the soil, providing a good environment for lawn grass growth. Improve the sprinkler irrigation facilities. Before lawn establishment, a full investigation must be made of the soil texture, water retention and fertilizer retention capacity of the site, and careful planning must be carried out. From an economic and practical point of view, impact sprinklers are a better choice, as they are easy to maintain and inexpensive. During installation, sprinklers can be set at a coverage radius of 6m2 to minimize spray blind spots. Sprinklers with a spray range of 8m sold on the market, due to the influence of water pressure and other factors, usually have a spray range of about 6m2 and can be selected. According to water demand, water pressure and the number of sprinklers, select main pipes and branch pipes of suitable size to ensure the sprinklers can spray sufficient water. The pipeline should be laid at a depth of 80cm below the soil layer, and the sprinkler should be 30cm above the ground for a better spray effect. According to the area of the planting site, the installation of drainage ditches should also be considered.

2 Lawn planting methods

Most lawns can be sown in spring or autumn, and sowing in late autumn produces uniform seedlings. When establishing a lawn over a large area, a seed drill can be used for sowing, while small areas are all sown by hand. After sowing, rake once lengthwise and once crosswise with a nail harrow, then press with a wooden roller. After sowing fine seeds, rice straw should be covered to preserve soil moisture. The sowing method requires skilled broadcasting technique to ensure even seeding.

2.1 Sodding method

Although this method can quickly establish a lawn, the process is too complicated and the investment is relatively large.

2.2 Stem broadcasting method

All grass species with well-developed stolons, such as bermudagrass, carpet grass, fine-leaf zoysia, creeping bentgrass, buffalo grass, etc., can be propagated by the stem broadcasting method. The best time is in early spring when the turf is just about to sprout, and it can also be done in the rainy season. First cut creeping stems from the lawn area, cut them into 5~8cm long segments in the shade; each segment must have 1 node, otherwise it cannot sprout new roots. Then carry out drilling or broadcasting. Drilling: on the leveled ground, open shallow furrows with a small hoe, irrigate fully, and after the water infiltrates, place the stem vines in bundles of 2~3 along the furrows, cover with 1cm of soil, with a row spacing of about 20cm, then spray water once a day, and stop spraying after new buds emerge. Broadcasting: evenly scatter the cut stem segments on the soil surface and cover with 1cm of fine soil.

2.3 Root planting method

This method is suitable for grass species that have no stems or vines but have many tillers, such as carex and velvet grass. The best time is in early spring or the rainy season. Dig out the roots of the lawn in dense areas, shake off the soil, remove weeds, cut off some fibrous roots, divide into clumps of 2~3 seedlings, tear them apart, and then plant them in holes or rows at a certain spacing between plants and rows. Cover with soil as you plant, with a suitable soil cover thickness of about 2cm. After covering with soil, press lightly and irrigate thoroughly. Before new leaves sprout, spray water 1~2 times a day to prevent soil crusting and cracking. Under normal circumstances, the simpler, easier and more money-saving methods for planting turf are the stem broadcasting method and the root planting method.

3 Management after lawn establishment

3.1 Comprehensive management

① In the first year, weeds must be constantly removed. ② Prune in time. Prune when the grass grows to 4~10cm high, and the amount pruned each time should not exceed half of the grass height. Lawns generally maintain a height of 2~5cm. ③ During the growing season, it is advisable to apply granular mixed fertilizer of nitrogen, phosphorus and potassium. Generally apply after pruning and before sprinkler irrigation. ④ Lawns should not be used excessively. Periods of use and maintenance periods should be specified, and use should be opened in rotation by sections on a regular basis.

3.2 Watering

Watering can not only maintain the normal growth of lawn grass, but also improve the toughness of stems and leaves and enhance the lawn's resistance to trampling.

3.2.1 Season: Lawn irrigation should be carried out in dry seasons when evaporation exceeds precipitation. After the lawn soil freezes in winter, there is no need to water.

3.2.2 Time: As far as weather conditions are concerned, a gentle breeze is the best time for irrigation, as it can effectively reduce evaporation loss and help the leaves dry. Morning and evening are the best times to water, but watering at night is not conducive to the drying of lawn grass and easily causes disease.

3.2.3 Water amount: Usually, during the dry period of the lawn grass growing season, to keep the lawn grass fresh and green, about 3~4 supplementary waterings per week are needed; under hot and dry conditions, vigorously growing lawns need 6 or more supplementary waterings per week. The amount of water required depends to a large extent on the texture of the lawn bed soil.

3.2.4 Method: Watering can use various methods such as sprinkler irrigation, drip irrigation and flood irrigation, and different methods can be adopted according to different levels of maintenance and management as well as equipment conditions. To maintain the lawn, 1 watering each should be given before the lawn grass stops growing in autumn and before it turns green in spring, and it should be watered sufficiently and thoroughly, which is very beneficial for the lawn grass to overwinter and turn green.

3.3 Topdressing with sand

Topdressing with sand and soil is a prerequisite for obtaining a high-quality lawn, protecting the lawn's root system and growing points; topdressing can also promote lawn growth and enhance lawn vitality. The topdressing material can be sand, sandy loam or a sand-fertilizer mixture. After topdressing, it is recommended to carry out raking, followed by vertical mowing and overseeding operations.

2.4 Scarifying

If the lawn soil is not only compacted at the surface layer but also very compacted in deeper layers, thorough scarifying is needed, and this operation requires the use of a vertical scarifier. The effect is best when topdressing with sand immediately follows scarifying. After scarifying, after several passes of net dragging and leveling, the topdressed sand will enter the holes formed by scarifying. The best time to scarify with a vertical scarifier is spring or autumn.

4 Lawn disease control

4.1 Classification of lawn grass diseases

According to different pathogens, diseases can be divided into 2 categories: non-infectious diseases and infectious diseases. The occurrence of non-infectious diseases lies in 2 factors: the lawn and the environment. Examples include improper selection of grass species, lack of nutrients necessary for lawn grass growth in the soil, imbalance in the proportion of nutrient elements, soil that is too dry or too wet, and environmental pollution. Such diseases are not contagious. Infectious diseases are caused by fungi, bacteria, viruses, nematodes, etc. Such diseases are highly contagious, and the 3 necessary conditions for their occurrence are: susceptible plants, highly pathogenic pathogens and suitable environmental conditions.

4.2 Control methods

4.2.1 Eliminate the sources of primary infection of pathogens. Soil, seeds, seedlings, diseased plants in the field, diseased plant residues and undecomposed fertilizer are the main places where most pathogens overwinter and oversummer. Therefore, measures such as soil disinfection (commonly using formalin disinfection, that is, formalin:water=1:40, 10~15L/m2; or formalin:water=1:50, 20~25L/m2), seed and seedling treatment (including quarantine and disinfection of seeds and seedlings; the commonly used disinfection method on lawns is: soak seeds in a 1%~2% diluted formalin solution for 2~60min, then take them out, wash them clean, dry them and sow) and timely elimination of diseased plant residues should be adopted for control.

4.2.2 Agricultural control. Match grass to the site, especially selecting disease-resistant varieties, removing weeds in time, deep plowing and fine fertilizing in due season, timely handling diseased plants and disease occurrence sites, and strengthening water and fertilizer management, etc.

4.2.3 Chemical control. That is, spraying pesticides for control. In general areas, before various lawns are about to enter vigorous growth in early spring, that is, before lawn grass is about to develop disease, spray an appropriate amount of Bordeaux mixture 1 time, then spray 1 time every 2 weeks, for 3~4 consecutive sprays. This can prevent the occurrence of many fungal or bacterial diseases. Different types of diseases require different pesticides. However, attention should be paid to the use concentration of the pesticide, the time and frequency of spraying, and the spray amount. Generally, the effect of spraying is good when lawn grass leaves remain dry. The number of sprays is mainly determined by the length of the pesticide's residual effect period; generally 1 time every 7~10d, for a total of 2~5 sprays. After rain, additional spraying should be done. In addition, various pesticides should be mixed or used alternately as much as possible to avoid the development of pesticide resistance.

5 Lawn pest control

5.1 Main reasons causing pest damage to lawn grass

Before lawn establishment, the soil was not treated for pest prevention (deep plowing and sun-drying the soil, digging the soil and picking out insects, soil disinfection, etc.); the organic fertilizer applied was not decomposed; early control was not timely or the pesticide was improperly used or ineffective, etc.

5.2 Integrated control of lawn grass pests

5.2.1 Agricultural control. Match grass to the site, deeply plow and sun-dry the soil before sowing, pick out and remove insects while digging, apply fully decomposed organic fertilizer, and manage watering in due season, etc.

5.2.2 Physical and manual control. Light trapping, contact killing with pesticide-treated soil, manual capture, etc.

5.2.3 Biological control. That is, using natural enemies or pathogenic microorganisms for control. For example, the main effective pathogenic microorganism for controlling white grubs is Metarhizium anisopliae, with a control efficacy of 90%.

5.2.4 Chemical control. Insecticides are mainly organophosphorus compounds. Generally, after application, irrigation should be carried out as soon as possible to promote the dispersion of the pesticide and avoid losses from photodecomposition and volatilization; spraying is commonly used for pests on the soil surface. However, for some pests, such as when controlling lawn webworms, irrigation after application should be carried out at least 24~72h after application. Common methods are seed dressing with pesticides, poison bait trapping or spraying.