All you need is water and maybe a little compost/vermicompost tea during the season. No other nutrients needed. This is a Canna forum so if you are at work you may want to look later at home.
http://forum.grasscity.com/organic-growing/1116550-easy-organic-soil-mix-beginners.html
http://forum.grasscity.com/organic-growing/1116550-easy-organic-soil-mix-beginners.html