How to prepare Bordeaux mixture?

In fact, many friends are not familiar with Bordeaux mixture, but farmers may know more about it. Bordeaux mixture, also known as protective fungicide, is made by mixing liquid copper sulfate and liquid quicklime. Such a solution is generally prepared for use in the prevention and control of plants such as fruit trees and vegetables, allowing the plants to grow more smoothly.

Overview

Use half the amount of water to dissolve the copper sulfate and the other half to dissolve the quicklime. After they are completely dissolved, slowly pour both into a spare container at the same time, stirring constantly. You can also use 10% to 20% water to dissolve quicklime and 80% to 90% water to dissolve copper sulfate. After they are fully dissolved, slowly pour the copper sulfate solution into the lime milk, stirring while pouring to form Bordeaux mixture. But never pour lime milk into copper sulfate solution, otherwise the quality will be poor and the effect will be poor.

Specific steps

(1) Divide the total amount of water used in the preparation into two equal parts. One part is used to dissolve copper sulfate to prepare a copper sulfate aqueous solution. 1 part is used to dissolve quicklime. First, soak the quicklime in a small amount of hot water to allow it to absorb water and react fully to generate calcium hydroxide (in the form of mud). Then, sift the prepared lime mud through a fine sieve and add it to the remaining water to prepare lime milk (calcium hydroxide aqueous solution).

After the two liquid medicines are prepared, they do not need to be mixed immediately. They can be temporarily sealed in containers and mixed for use when spraying. When preparing the medicine, slowly pour two equal amounts of liquid medicine into the sprayer or another container at the same time, stir while pouring the liquid medicine, and use it immediately after stirring evenly.

If you use a mechanical sprayer, you must prepare a large amount of liquid medicine at one time. You can use the siphon principle to tie small stones to the bottom of two thin plastic hoses of equal thickness and length (the length must be more than twice the height of the container). Sink them to the bottom of the two solutions respectively, and then fill them with the solution. Use your thumb to seal the upper end of the pipe and pull it out to another container fixed in a lower position. The solution will flow out by itself. Adjust the flow direction of the solution at the pipe mouth, let it rotate by itself, and then insert it into the sprayer water suction tap.

(2) Use 10% water to prepare lime milk to make a calcium hydroxide aqueous solution, and use 90% water to dissolve copper sulfate to make a copper sulfate aqueous solution. The two solutions are temporarily stored for future use. When spraying, the medicine must be prepared and used immediately. First, pour 1 part (10%) of lime water solution into the sprayer or another container according to the proportion, and then slowly pour 9 parts (90%) of copper sulfate water solution into the lime water solution in the sprayer. Stir while pouring the solution, and use it immediately after stirring evenly.

Note: Because the preparation of Bordeaux mixture must be carried out under alkaline conditions, the order must not be wrong when pouring the solution. The copper sulfate solution must be poured into the lime solution, and the lime solution cannot be poured into the copper sulfate solution, otherwise the prepared solution will precipitate immediately and become ineffective.

(3) A simple method is to add copper sulfate, quicklime and water in proportion.