I managed to collect some A. pseudosieboldianum seeds from the Japanese park in Tallinn. I kept these seeds some months in a dry place and sowed these seeds in February into containers, with peat, sandy soil and horse manure mix as a growing medium. Today I found that seedlings are just starting to emerge from the soil. Should I wait for first real leaves before I transplant from sowing container into single plant containers? I have no former experience with growing oriental maples from seed.