My first advice is that if what you are doing gives good results for you don't change it. If particular seed cause problems however, try my Propagator, Glass & Fibre technique (PGF for short). If the seed are rare try a number of different treatments in case a batch rots. Why use the PGF technique? It's fun! It is really interesting to be able to see how the seed cracks open & how the young seedling develops. A wonder of nature. Also what I had never realised was that the complex shape on the outside of the seedcoat is mirrored internally. I had always thought it to be smooth. As long as they are moved before the roots go through the fibre, which fortunately takes a few days, the survival rates are virtually 100% ..as good as soil. Even if the roots are snapped many come through well. I do not let metal touch them however...using an old horn eggspoon & gentle fingers instead.
Light is there the moment the seedling needs it - giving a strong seedling, though it does not speed germination. This is particularly helpful for small seed such as Decaloba with limited enery stores, which could try to come up from soil & if too deep won't make it.
Water. It is so easy to over or underwater soil especially when it is at a high temperature & there is nothing worse than seed either rotting or drying out. Again small seed are particularly vulnerable. A main factor of failing could be drying out of the seeds. PGF avoids that. Once PGF is set up with clingfilm over the top, or better still thick non permeable plastic, it needs little attention with capillary action regulating the moisture level in the seed & the humidity being very high. Easier for beginners. The instructions that follow give a good success rate with most fresh Passiflora seeds. AT least none of these suggestions should decrease germination rates. Note however that even if you have fresh wet fully ripe seed, the mix of the parents' genetic characteristics (if it has been hybridized) cannot be controlled & even if you do everything right the seedlings may be weak & sometimes very variable. Equally you will sometimes get a batch of seed which are all vigorous & will thrive despite being poorly cared for. I use bottom heated propagators for presoaks & germination. Their bases are lined with a layer of sharp sand - which helps retain the heat much better than the mats usually supplied. Good seed to practice your skills on would be either P. caerulea or passion fruit bought from the grocer or supermarket. more >> | 
Passiflora soilless seed sowing
