To change the acidity or alkalinity of flower soil, first understand the soil type
Soil is an important medium for flowers and one of the environmental factors on which flowers depend for survival. The physical properties of soil and soil pH both have a certain effect on the growth and development of flowers. So, how do you change soil pH?
Classification of soil texture
Soil texture refers to the physical condition of the soil, that is, it reflects the degree of sandiness or clayiness of the soil. According to the degree of sand and clay, soil is generally divided into three major categories: sandy soil, clay soil and loam.
1. Sandy soil has large gaps between soil particles and holds little water. It has good aeration and water permeability, but poor water- and fertilizer-holding capacity.
2. Clay soil has small gaps between soil particles and poor aeration and drainage. It is muddy when wet and hard and compacted when dry, and has a strong water- and fertilizer-holding capacity.
3. Loam has the advantages of both sandy soil and clay soil. It has good aeration and water permeability and a strong water- and fertilizer-holding capacity, making it suitable for flower growth.
For flowers grown in the open field, since the root system can extend freely, the underground part requires sufficient nutritional space. For this reason, it is enough to choose a loamy cultivation site with deep soil, good aeration and drainage conditions, and a certain level of fertility. Before transplanting, the soil must first be prepared.
Through soil preparation, combined with increased application of organic fertilizer, the physical structure of the soil can be changed, the soil's aeration and water permeability conditions can be improved, which is beneficial to the activity of soil microorganisms, accelerates the decomposition and transformation of organic matter, makes the soil loose, facilitates root activity, and promotes the growth and development of flowers. At the same time, after transplanting, loosen the soil and hoe weeds in time. On the one hand, this eliminates the compaction caused by irrigation and rainfall and makes the surface soil loose; on the other hand, it removes weeds.
Methods for changing soil pH
(1) Add 0.5 to 1 kilogram of sulfur powder per cubic centimeter. Sulfur powder takes effect slowly, but lasts a relatively long time. When using a small amount, for a flower pot with a diameter of 30 cm, adding 1 spoonful of sulfur is enough.
(2) For each cubic meter of potting soil, add 0.5 to 0.75 kilograms of aluminum sulfate (white alum), which can turn neutral soil into slightly acidic soil. Potted flowers can also be regularly watered with a 1:50 white alum aqueous solution.
(3) Water flowers with a 1:200 ferrous sulfate (black alum) aqueous solution, once every 7 to 10 days, and once every 15 to 20 days in winter. Black alum water takes effect quickly, and the iron ions it contains help promote the formation of chlorophyll, so after watering, the branches and leaves of the flowers can become deep green. For households growing acid-loving flowering plants such as jasmine and camellia, some black alum can be purchased. Add 1 to 2 grams of black alum per pot of flowers and water with 0.5 to 1 kilogram.
The method of lowering soil acidity often uses the application of lime. The amount applied can be determined according to the degree of soil alkalinity. Generally, adding 0.25 to 0.5 kilograms of quicklime per cubic meter is enough. For home flower growing, where the amount of soil to be improved is small, limestone blocks or lime wall debris can be added for improvement.