bletilla striata potting

[neophyte]

hello, i just received three small (but healthy-looking) bletilla striata plants through ebay. i am not sure how deep to pot the tuber/bulbs in the soil. i have just potted them with the tubers barely a centimeter below the soil because i did not want to cover up any of the leaves/shoots with dirt. however, several websites are telling me to pot deeper in the soil. one website said 5 - 10 cm, while another said 5 - 6 in! what is the correct potting depth? also, is there a chance that the plants will flower this year? if not, when would the leaves die back?