Effect of moisture content in cultivation medium

The growth of national orchid must have water in order to maintain its growth, nutrient absorption and transport, and normal metabolism.

National orchid is a semi-air root negative plant. In the process of growth, a small part of the water is absorbed by the moisture in the air through the leaves, and most of the water must be absorbed by the water contained in the cultivation medium. supply the national orchid with new organic matter for growth and proliferation.

In addition to the energy produced by leaf photosynthesis, the root row respiration is absorbed into the pores of the media in the orchid basin.

Oxygen, such as too much moisture content in the medium in the orchid basin, the water will fill the pores of the medium, resulting in stagnant water, the pores of the media in the basin are full of water and lack of oxygen, the roots are asphyxiated due to hypoxia, and the roots are prone to rot.

If there is too much water content in the medium in the orchid basin, fresh oxygen cannot enter the pores of the medium from outside the basin for gas exchange, and the roots of the orchid will carry out its normal physiological function in order to obtain fresh oxygen. There will be a phenomenon of root growth-- that is, most of the roots of the orchid will stretch around the pores at the edge of the orchid basin, or grow to the place where there is fresh oxygen at the top of the basin. On the other hand, in the middle part of the root system with high moisture content and poor air permeability in the orchid basin medium, due to the lack of oxygen supply, the root system has no semi-permeability and loses its original function. At this time, due to the proliferation of anorexic bacteria, waiting for an opportunity to invade the harm. And due to the accumulation of a large number of toxic substances to poison the root system, the life of beneficial microorganisms is limited, the intermediate products can not be decomposed for root absorption, the root function is gradually lost, and the ability of the root system to absorb water and nutrients is reduced. As a result, the root system will rot and die, indirectly affecting the stem and leaf growth of the national orchid.

The water content of a general medium is closely related to its physical properties and particle size. The larger the particles, the more non-capillary pores, the water is easy to lose from the pores, and the water is not easy to maintain; the smaller the particles are, the more capillary pores are, the water is less easily affected by gravity, and the water is easier to be maintained. therefore, the water retention capacity is higher.

After the large particle medium is planted in the orchid body, a lot of space is formed between the particles to make it easy to lose water, and the management of water and liquid fertilizer must be very careful; after the fine particle medium is filled in the orchid bowl, its water retention capacity is good, and its ventilation becomes worse. Special attention must be paid to water management, otherwise it is easy to cause the orchid root to lack oxygen and give birth.

In general, the larger particles are coarse Japanese stone, coarse sand, coarse perlite, mineral silica, long snake wood chips, coarse bricks, and fine particles on peat, artificial soil, sawdust, fine snake sawdust and so on.

The larger the particle is, the worse the water retention is, the root system of Iris chinensis is easy to stop growing due to lack of water, the finer the particle is, the higher the moisture content is, the oxygen diffusion is limited, and the root system of Guolan is easy to rot due to anoxia. Due to the mutual use of an appropriate amount of coarse-grained medium and fine-grained medium, it can increase ventilation and water retention, supply sufficient oxygen and water to the root system, and reduce the number of fertilizers.