Here's a quick post on how a Leptotes bicolor grows. As Leptotes are in the Cattleya alliance, you'll see that their flower spikes grow from the base of the new leaves rather than the base of the plant. Thus you won't have trouble distinguishing new growths and roots from a flower spike.
First, lets see that a flower spike is much farther up from the base compared to a new growth. Below you'll also see that it can be somewhat confusing at first distinguishing between small old growths and a new growth. Small, old growths are from when the plant was first starting and lacking the nutrients to grow to its full potential; once they start growing a new growth, the old growths stay the same size. A new growth, however, usually is a bit paler and isn't as smooth, due to the segmented sheath that surrounds it.
Finally, the roots are distinguished by being very smooth, with only the velamen and the root tip distinguishable (i.e. no sheath)