How to disinfect seedlings after division? Liwei's Watering, Part 2

Liwei "Watering" - 2 (Disinfection After Division) PersonalOrchid growinga few reflections, for reference only! Brickbats welcome, When the plants need dividing, it is time to get to work.Cymbidium goeringiiis relatively easy to handle. Grasp the pseudobulb and the top part (watch the young shoots carefully, do not touch them - touch them and it's all over), shake gently sideways to find the "road" (the natural separation line), then pull apart, cut apart or slice apart, whichever gives the smallest wound surface.Cymbidium goeringiiFor strong plants with good roots and large pseudobulbs, dividing into groups of 3-5 shoots works best - best for producing new shoots, blooming and growing strong plants. Growers with a high level of skill can also grow single shoots (I'm a novice and am experimenting with Song Mei and Ji Yuan), though blooming is estimated to be difficult. Weak plants with few roots and small pseudobulbs are better left as connected clumps to regain strength. Cymbidium faberi (Huilan) is sometimes more troublesome: dense roots, dense foliage, small pseudobulbs, and the "road" is hard to find. And even when you find it, you probably can't get the scissors in - a headache! In that case you have to comb the roots: lay the Huilan plant with roots up and foliage down at an angle, and with both hands gently comb the roots apart strand by strand to expose the junctions between the pseudobulbs. Now you need a third hand - the scissors must go in accurately and decisively, snip, and it's done. If the scissors won't go in, use a medical hook-shaped scalpel with a handle; now you may need a fourth hand. The scalpel should be inserted between the pseudobulbs of the two clumps after prying them apart slightly. The blade is very sharp, so do not injure the pseudobulbs - hold the orchid plant and the scalpel handle steady and force the blade down through the exposed junction between the pseudobulbs. (Be sure - if not sure, give up and look again.) When dividing Huilan, it is best to keep clumps of 3 or more shoots connected. Also: books say that twisting old pseudobulbs 180 degrees without separating them can still produce new shoots. I followed the books and tried it - some produced shoots, some went to heaven. Not pleasant! I separate what can be separated and leave what cannot. But what about plants you both want to divide and don't want to divide? Then gently pry the two pseudobulbs apart just enough to see a split wound. The wound is small: if it produces shoots, great; if not, it won't die. This method suits spring after the flowering period or the mild "little Indian summer" of autumn, when the shoot production rate is higher. After late autumn, temperatures are lower, the wound gradually heals and cannot stimulate bud development, so the shoot production rate is not ideal. Now it is time to disinfect and sterilise. Orchid plants: Use thiophanate-methyl at 800-1000 times dilution, soak for 30 minutes, or carbendazim at 800-1000 times dilution, soak for 30 minutes - either works. Then air-dry and plant. Tools: metal ones such as scissors, blades and tweezers should be sterilised by flame - an alcohol lamp is better. Potting medium: new Xiantu (orchid soil) and Zhijinshi (pumice) can be used after being sun-baked for a few days, (Xiantu must be soaked through). Pots: new ones need no disinfection; the key is old ones. First sun-bake for a few days, then soak in potassium permanganate at 500-800 times dilution (duration unspecified). After soaking, wash clean and air-dry for 3-5 days before use (after the potassium permanganate has lost its effect). Everyone knows potassium permanganate is a catalyst; my understanding is that it is a strong oxidiser. It can kill all living cells on the surface. Has anyone's hand ever been soaked in potassium permanganate at 500-800 times dilution, even briefly or by unconsciously touching it? Then the skin of the hand will turn yellow, and after a few days the outer skin will peel off. Likewise, while killing bacteria it also kills good living cells, such as: roots, leaves, pseudobulbs, bud points, hands, feet, skin, etc. [Liwei's Watering -- 3 (Pots and Potting Medium)