Seedling maintenance is very important in landscaping engineering, and maintenance management is related to the success or failure of the whole landscape design project。This paper mainly analyzes and explains the basic knowledge of seedling greening maintenance and irrigation in landscaping engineering。

The water absorbed by seedlings from soil mainly comes from rainwater, groundwater and irrigation water。In the arid areas in the north, the water in the soil is mainly replenished by irrigation。However, if there is too much rain or poor drainage, it will also affect the respiration of seedlings, and seriously lead to root rot or even death。

1. Irrigation quantity and irrigation times

1.Irrigation of different cultivation methods

(1) After seeding, try to avoid dry topsoil, especially in northern regions, where some small seeds are covered with shallow soil after seeding, which is vulnerable to spring drought。Through reasonable irrigation, the bed surface is kept moist to prevent water loss of young seedlings, and the surface temperature can be adjusted to prevent sunburn。Generally, more irrigation times are required, and less water is required each time。

(2) cuttings, layering, and buried seedlings require a large amount of water for rooting and germinating, especially at the beginning of leaf spread and not yet fully rooted (that is, pseudophylric) stage, with large leaf surface transpiration and less soil water supply, and the plant will die once water is cut off. Timely irrigation is the key。In the north, the climate in the dry season should pay more attention。The amount of irrigation can be appropriately large, but the water flow should be fine and slow, so as not to move the seedlings (especially cuttings) by the rush of water.。

(3) Branch seedlings and transplanted seedlings These seedlings due to root injury during planting, the water supply inside the seedlings is unbalanced, and the water supply must be strengthened。After subdivision and transplantation, water should be injected three or four times, the amount of irrigation should be larger, and the interval should not be too long。

(4) Grafting seedlings The need for water is not too large, as long as it can ensure the normal life activities of the rootstock。Water should not be too much, especially in the interface area, otherwise it will make the wound rot。Also pay attention when irrigation is necessary in dry weather。

(5) Irrigation is required for large seedlings only in the dry season。If there is too much water, it will also reduce the resistance of seedlings and affect the growth and development。

2.Irrigation under different climatic conditions

Irrigation must be flexible in response to changing climatic conditions。Generally speaking, from spring to early summer, seedlings are in a vigorous growth period, and there is more rain in the south, as long as irrigation is three or four times?It's a dry season in the north. We need to irrigate seven or eight times。Sowing seedlings and cutting seedlings require more irrigation。

Early summer, the south is rainy season, pay attention to drainage。In summer, there is often a rainy season in the north。The south is different, if the high temperature and drought, must increase the number of irrigation。In autumn, although the rainfall is different from the north to the south, in order to enrich and lignify the seedling tissue and prepare for winter, it is generally not irrigated。In winter, the south does not irrigate, and the north should irrigate frozen water once before the land freezes to facilitate the overwintering of seedlings。

3.Irrigation of different soil conditions

The water retention capacity of viscous soil is strong, and the irrigation amount should be reduced appropriately.The water retention capacity of sandy soil is poor, so the irrigation water should be increased appropriately。

4.Irrigation of different tree species

Different tree species have different water requirements, the seedling stage is not too different, and generally need to have enough water。With the growth of seedling age, the difference becomes more and more obvious。For some drought-tolerant tree species, such as ailanthus, acacia, cloves, etc., attention should be paid to immediate drainage when the water is long。For general tree species, it is necessary to keep moist state frequently, and determine the appropriate irrigation amount combined with the groundwater level and rainfall。

Second, irrigation methods

1.Surface irrigation

In high bed and ridge working areas, water can be channelled into walks or furrows by irrigation channels, and water can penetrate into beds or ridges from the side。Its advantage is that the soil still has good ventilation after irrigation, which can reduce the number of soil loosening and save labor, but the water consumption is too large, and the wide seedling bed will produce uneven irrigation。

Low bed or field type seedling area, water can be directly introduced into the low bed or bed surface by irrigation channels, water covered the bed or bed surface and gradually deep into the soil, which is flood irrigation。This method is more convenient when irrigating, but it should be noted that the water speed should be slow, so as not to wash down or flood the seedlings。After irrigation, the soil is easy to compact, poor ventilation, to increase the number of soil loosening。

2.Sprinkler irrigation and drip irrigation

Spray irrigation is generally suitable for large seedling irrigation, and drip irrigation is suitable for seedling bed irrigation, which are relatively advanced irrigation methods。

3. Drainage

Water should be removed from the ground in time after rainfall or heavy irrigation. Water should not be allowed in nursery land, otherwise it will reduce the decomposition rate of soil organic matter, destroy the normal respiration of seedling roots, and often cause root rot or even death。