Hallo!

First: yes, microbes can grow on plain agar. (microbes nearly grow EVERYWHERE)

You can autoclave the agar, and I hope you do, so there will be less contamination when you work sterile.

Second: Try This: When willows (Lat.: Salix) are growing nearby, cut some thin branches, cut them into small pieces (2cm or 1inch long), pour over cooking water and let stand for few hours (12 - 24h, RT) then strain the branches and (and this is very important!!) make a sterile filtration (0,2µm or smaller) and freeze at -20°C. (otherwise it will moulder in few days or contaminate your Nepenthes!)

When you want to use it: dilute 1/10 with (sterile) water or whatever you use (buffer or thin saline or wahtever). incubate seeds or cutted plants for few hours (not longer than 6 hours) and then bring into media (whatever you use: agar...it also work at home on the balcony with most plants)

The Willow contains big amount of plant grows hormones. Seeds germinate much faster, and cutted plants will grow roots much faster than normal.

Good luck and much fun, I love carnivorus plants

thanks Ninon, I'll try that for the seeds etc. I did try using the branches of the willow next door for rooting household plants in vivo but didn't think to try it with my nepenthes in-vitro. Its very cold here now and the branches are dormant so think I'll wait till the spring unless you think they produce the hormones all year round?

we germinate on moist cellulose tissue paper, no added salts or other compounds. The seed has enough resources to germinate!

put these seeds on moinst cellulose tissue paper in the Plastic box and close hermetically and put in the dark.

thanks I'll  germinating on  the tissue paper and transfer seedlings to agar