1. The watering amount varies with plant species. Generally speaking, herbaceous flowers should be watered more and woody flowers should be watered less. Ferns and orchids need rich water in their growing period; The pulp mill needs less water. Different growth stages of the same plant need different amounts of water. When entering the dormant period, the watering amount should be reduced or stopped; When entering the growth period, the amount of watering should be gradually increased; When the growth is vigorous, the amount of water should be sufficient. The water demand of the same plant varies greatly in different seasons. If North China is dry in spring and summer, and the evaporation is large, it is necessary to water it frequently and more. Although it is hot at the turn of summer and autumn, there is a lot of precipitation, so you don't need to water it too often.
2. Determination of watering time. At noon in summer, the soil temperature is high and the water temperature difference is great. If you water at this time, the soil temperature will suddenly drop, and the roots of plants will be stimulated by low temperature, which will hinder the normal absorption of water. So watering in summer should be done in the morning or at night. In winter, the temperature is low, the sunshine is weak and the water demand is low. In permafrost-free areas, garden plants cultivated in the open field in winter should be watered around noon to avoid freezing injury caused by watering in the morning and evening. Before the soil is frozen, "frozen water" should be poured to keep the soil moisture. At the beginning of soil thawing, we should also water "turning green water" to facilitate the germination of garden plants.
3, watering times. The watering frequency should be determined according to the seasonal change of climate and the degree of dryness and wetness of soil. Water plants regularly to keep the soil moist; Xerophytes need less watering times, and each watering interval can be dry for several days; Mesophytes should be watered both wet and dry, and the soil should be thoroughly watered when it is dry. Like wet garden plants, such as willow, Metasequoia glyptostroboides, Taxodium ascendens, etc., it is necessary to water them a few times; However, seedlings such as Fraxinus mandshurica, Pinus tabulaeformis and Pinus tabulaeformis are drought-tolerant, and the irrigation times can be appropriately reduced.
4. Water quality. The quality of irrigation water is usually divided into hard water and soft water. Hard water refers to water containing a lot of metal ions such as calcium, magnesium, sodium and potassium; Soft water refers to water containing less metal ions. Too high or too soft water quality is not conducive to plant growth, so it is best to water garden plants with slightly acidic or neutral water. Before watering garden plants with tap water or drinkable well water, you should bask in the water one or two days in advance. One is that chlorine in tap water can be volatilized, and the other is that the water temperature can be increased.
5. Spray water on the leaves. The water needed for the growth and development of garden plants is absorbed from soil and air, mainly from soil, and also needs a certain degree of air humidity, so foliar spraying can not be ignored. Spraying water on plant leaves can increase air humidity, reduce temperature and wash away dust on plant leaves, which is beneficial to plant photosynthesis. Generally, we pay attention to watering plants, but we often ignore that plant leaves also need water. In addition to directly watering the soil, it is also necessary to maintain the humidity of the air by spraying water to meet the requirements of garden plants for water.