I use a top layer of peat moss to cut down on algae. My last batch was the yellowish NZ spaghnum, but now my current batch consists of the darker brown spaghnum.
NZ sphagnum by itself works great for most Drosera. I used milled sphagnum for sowing seed as the growth rate(for me) was 4 X better than peat sand. Now mind you, the silica sand I used was rather fine, so maybe peat /sand was too compact. I used xvart's mix on a N. alata once and it grew great in that.
I have turned to adding perlite to the sphagnum, not because it's necessary, but because it's cheaper, lol.
I have always managed to let the bottom of the tank dry before adding water, so maybe that is why sphagnum works so well for me.
its uhh... light brown... its not yellow, its light brown...