What is the reason for cactus rot?
As a representative of desert plants, the problem of rotten roots in cactus often leaves conservators at a loss. Its fleshy root system is extremely sensitive to water and nutrients, and it is necessary to accurately grasp the key points of maintenance to avoid root damage. Systematic analysis of common mistakes can help plants quickly return to health. The three major inducements of cactus root rot are caused by improper fertilization. Undecomposed organic fertilizers release a lot of heat, while high-concentration chemical fertilizers directly burn the roots. It is recommended to use special slow-release fertilizer for cactus. Liquid fertilizer with a concentration of ≤0.3% should be applied every month during the growth period, and fertilization should be completely stopped during the winter hibernation period. More than 80% of root rot cases where accumulated water causes root suffocation are due to improper watering. Cactus must follow the principle of "dry thoroughly and irrigate thoroughly", and the dipping basin method can ensure uniform penetration of water. The matrix with a ratio of 60% particulate soil in the pottery basin can effectively prevent water accumulation. Insufficient light weakens resistance. Light <4 hours a day will cause plants to grow slowly, and new roots will be fragile and easy to rot. It is recommended that the southbound window sill receive direct light all year round, and a 30% sunshade net can be added at noon in summer to prevent skin burns. Rescue Plan for Cactus Rotten Roots Scientific treatment found that rotten roots should be removed immediately, and disinfected scissors should be used to remove the browning tissue to retain the milky white healthy root system. Apply plant ash or carbendazim suspension to the wound, and let it dry for 3-5 days until the wound conjunctiva is finished before applying to the basin. The maintenance environment was rebuilt and replaced with a new matrix of volcanic rock + vermiculite + coarse sand (ratio 3:2:1). It was initially placed in a scattered light environment, and gradually increased light after 2 weeks. Maintaining a temperature difference of 10℃ between day and night during the restoration period can stimulate the germination of new roots. Precise water and fertilizer management suspended fertilization for the first month after root pruning, and spraying was used to maintain micro-moisture in the substrate. After new roots are grown, the drip irrigation system is switched to, combined with EM bacterial solution irrigation, can significantly improve root vitality. In spring and autumn, calcium-containing foliar fertilizers can be applied to strengthen cell walls.
By establishing a complete maintenance system of "prevention-monitoring-repair", the risk of cactus root rot can be minimized. The key is to understand its xerophytic characteristics, simulate the native environment, and achieve a dynamic balance between the three major elements of water, light, and nutrients. Regularly checking the state of the basin soil and adjusting maintenance strategies in a timely manner can keep the cactus root system strong.