Willeke, The use of the rooting hormone if it has a anti-fungicide in it would be beneficial. I have used Cinnamon (Ceylon) as an anti-fungicide on mine as well as a Sulfur dust. The only thing with the cinnamon and sulfur dust in the applications I have used, is that it is applied and allowed to air dry on cut surfaces for anywhere from 3-4 days up to 2-3 wks. This would not be something you would want to do with your seedlings. They would not survive out of soil this long.
My thoughts are that if you use cinnamon and then plant up in soil and water in, whether it be right away or a day later. It might just wash it off? Maybe not, just thinking out loud.
Rick
