After the black spots appear on the cactus, it is necessary to observe whether the meat and root rot. If rot occurs, remove rotten meatballs and rotten roots in time, and insert the removed cactus into the soil again
Because of the virus in the original soil, it is not suitable to continue to grow cactus. Therefore, it is necessary to mix the fine sand, mud and a little corrosive soil together to prepare the soil again. You can also add a little bit of broken stone or tree leaves for cactus drainage.
Cactus does not need too fertile fertilizer, to maintain the medium fertility. Phosphorus and potassium can be used to increase the fertility of the soil. But we should control the times and amount of fertilization.
When watering, do not drop water on the meat ball of cactus and the thorn on the surface, so it is easy to infect the virus. Water every 15 days or so.
There will be a wound on the surface of the cactus with the black spot removed. Put it in the sun to dry, and sprinkle a layer of charcoal powder on it to make the wound heal as soon as possible. Then, apply the medical dakinin ointment around the cactus spot, and sprinkle a little potassium permanganate on the soil.
