google will tell u that a true black rose does not exist, where as i have seen them. Resources also state that the only true black rose comes from jerusalem, so wats the deal, wats true and wats not?
Not sure if it belongs here...but a black rose is only black if it is dead or dyed.
Black roses are made from people adding dye to the water just like how they get blue and orange and green roses and all sorts of colors for them :)

That would be a photshopped pic...you can see the color contrast is off on the petals compared to the stem and the leaves around it.
That is true what TheDarkWolf said and I can see it to and he didn't say it doesn't exist just that to get a black rose it would either have to be dead or dyed :)
alright, here is a great link for small bits of infor regarding said black rose.
Black Rose
Wouldn't it be great if it was real? But alas it isn't. Did see a real yellow Magnolia tree so there maybe hope in the future. 'til then its Photoshop or dye.
~ billy