Normally, this command:
/particle reddust ~ ~1 ~ -1 1 0 0
should spawn a green particle.

As is told by the wiki (note that the -1 1 0 in the command are the xd yd zd):
"Reddust's default is a near-red (a random red tint between 0.8 and 1.0)... For example, with reddust, 0 0 0 produces a red particle, -1 1 0 produces a green particle (red is reduced to 0 and green increased to 1), 0 0 1 produces a purple particle (blue is added to the original red)..."
However, though I used -1 1 0 for my xd, yd, and zd, the particle still appears red.