Planting Tips

Chapter 47 Common Substrates for Soilless Culture of Flowers
The types are as follows.

(1) Water Water is the source of life.Water is an invisible, odorless liquid that is an excellent solvent for many substances.The root system in the hydroponic medium, on the one hand, absorbs the nutrients in the water, and on the other hand, puts some organic matter into the water and accumulates in the water.The characteristics of water as a soilless culture substrate: water and fertilizer are sufficient but oxygen is limited, and plants cannot be fixed.Therefore, it is necessary to artificially inflate or make the water flow in contact with the air to increase its dissolved oxygen, and use a grid to support the plants.Water quality directly affects the success or failure of soilless cultivation.

(2) Sand is a commonly used substrate in soilless cultivation, especially river sand.The characteristics of sand soilless cultivation substrate: stable water content, good air permeability, little infection of pests and diseases, and can provide a certain amount of potassium fertilizer.The disadvantage is that it does not retain water and fat.

(3) Ceramsite Ceramsite is a shale material that is fired at about 800% and has a relatively uniform particle size, red or pink.Ceramsite has a loose internal structure, many pores, similar to honeycomb, light texture, good water retention, drainage and air permeability, moderate fertilizer retention capacity, stable chemical properties, safety and sanitation, etc. It is a good soilless cultivation substrate, especially suitable for families Soilless cultivation of decorative flowers such as hotels, restaurants, etc.

(4) Vermiculite Vermiculite is a hydrated magnesium aluminum silicate, which is formed by heating mica-like inorganic substances to 800-1000 °C.

As a soilless cultivation substrate, vermiculite has the characteristics of strong water absorption, strong water and fertilizer retention capacity, and good air permeability. For most flower plants, vermiculite is a good soilless substrate.But it is not suitable for long-term use, otherwise, the porosity will be reduced, and the drainage and air permeability will be reduced.

(5) Perlite is a mineral formed from siliceous volcanic rocks, named after pearl-shaped spherical cracks.Perlite has the characteristics of good air permeability, moderate water content, stable chemical properties, and light weight. It can be used alone as a soilless cultivation substrate or mixed with peat and vermiculite.Its hydrogen ion concentration is higher than that of vermiculite, which is more suitable for planting acid-loving flowers in the south.

(6) Rock wool is a fibrous mineral, which is made by mixing 60% diabase, 20% limestone and 20% coke at high temperature.As a substrate for soilless cultivation, rock wool has the characteristics of low price, convenient use, safety and sanitation, suitable water-air ratio for many plants, and wide application.

(7) Silica gel Silica gel is a crystalline particle that swells after absorbing water. Its ability to absorb water and store nutrients is stronger than sand. The spatial distribution of plant roots in silica gel is clearly visible, which adds to the fun of soilless cultivation.

(8) Ion exchange resin is also called ion soil. It is a soilless cultivation substrate obtained by mixing the nutrients required by plants with cationic or anionic adsorbents such as epoxy resin in different proportions.Like other substrates, this matrix is ​​safe and hygienic, non-toxic and tasteless, and the ions adsorbed on the resin are released slowly for plant absorption.The disadvantage is that the cost is high, and it needs to be regenerated when it is reused.

(9) Peat Peat is the decomposed residue of peat moss, charcoal moss, moss and other aquatic plants.It has the characteristics of large water absorption, high nutrient absorption capacity, air permeability, and strong acidity. It is a commonly used substrate for soilless cultivation.Peat is often used as the main component of mixed substrates, and it is often used in conjunction with perlite, vermiculite, sand, etc.

(10) Sawdust Sawdust is a cheap soilless cultivation substrate, which is light, water-absorbing and breathable.But in the dry area in the north, because the permeability of sawdust is too strong, the root system is easy to air dry, causing the plant to die, so it is better to add some peat to make a mixed substrate.It is better to use sawdust from broad-leaved trees, and the chemical composition of some tree species is harmful.

(11) Slag Slag (coal slag) can be found almost in places where there are boilers. It is convenient to obtain materials and is suitable for use as a soilless cultivation substrate.The slag contains certain nutrients, contains a variety of trace elements, and is slightly acidic.

(12) Urine aldehyde and phenolic foam Urine aldehyde is what is commonly referred to as a sponge, which has a strong ability to absorb water and keep fat, has a small bulk density, and is easy to carry.Phenolic foam is also soilless with a small bulk density.Cultivation substrate, but because it does not absorb water, it must be mixed with large-volume sand and gravel.

(13) Composite matrix The composite matrix is ​​prepared from the above-mentioned single substrates according to the needs of plants, and the ratio of water and air in the matrix is ​​very suitable for root growth.The one prepared with inorganic matrix is ​​called inorganic composite matrix, the one prepared with organic matrix is ​​called organic composite matrix, and the one prepared with inorganic and organic matrix is ​​called inorganic-organic composite matrix.

There are many types of commonly used inorganic composite substrates, for example: a 2:1 substrate of ceramsite and perlite is suitable for planting various flowers with thick or fleshy roots.The ratio of vermiculite and perlite is 1:1, which improves ventilation and is suitable for cutting substrates.The ratio of slag and sand is 1:1, which can be used as cutting or cultivation substrate.Organic-inorganic composite substrates, such as peat, vermiculite, and perlite at a ratio of 2:1:1, have high water content and are often used in the cultivation of foliage plants.The ratio of peat and perlite is 1:1, which is used as cutting substrate.Peat, perlite, sand 1:1:1 substrate for potted plants.The substrate of peat and slag is 1:1, which is used for potted acid-loving plants.The substrate of peat and vermiculite is 1:1, which is used for cutting propagation.

(End of this chapter)