Hi everyone, I need some advice here!

I'm in my first year of PhD, only started less than 3 months ago and still very lost. My field is soil chemistry and my research topic is about cadmium uptake by potato plants. The idea is to first do a hydroponic experiment. Because studies explicitly focused on cadmium uptake by potato plants based upon hydroponic experiments are very limited, in fact there is actually this only one paper similar to what we want to do and can learn some experiment setups from.

The published paper isn't detailed in everything, and some practical things are missing. (e.g. potato plant was pre-grown in a Vermiculite media, but the paper didn't say for how much volume). Is it appropriate to directly email the author, to ask about details in his/her experiments, or even ask for the protocols?

I've heard that some authors are happy to receive questions about their publications, but I'm not sure about experiment setups.

Thank you in advance!

Most authors would happy to answer questions about their experiments if you ask nicely. Just be honest in your emails, saying what you want to know and what you are planning on doing. However, sometimes the corresponding doesn't know either because someone left or they simply forgot.

Yes, I'd agree, and also just add be polite and show your genuine interest in their work (which by the sounds of it you will do anyway :) so that it's not just asking for something and expecting it. Share a bit about your work too, as you've done here. Whether they still have protocol info might depend on how recent their publication is. Good luck!