Green plauge

Well I've kinda held this recurring nightmare back long enough. (5+ years I have it about 1-2 times a year)
I started out on the side of a street in a deserted area with a run down middle school with the door broken open with chains laying below. The sky in all of my dreams remains purple with three moons day or night. I walked over and peered inside. The lights were on and flickering in some rooms. To the left was the janitor room and to the right was the front desk area but wrecked with paper and miscellaneous things everywhere. There was two hallways that branched off and the wall was that cream white concrete block color. I walk over to the janitors door and push it open. I see a room sized shower with the drain in the middle of the floor with a standard round light in the ceiling. The hookup for the water was a very long water hose. I walked out and noticed the two hallways was now centered around a low metal fence with a 3/4s surrounded with a crude made brick wall. I walked over and looked over the edge to see nothing but darkness. The area across the darkness was just out of reach with a table sitting on the floor with something blurry sitting on it. I heard a light bulb blow then I looked to my right and this green...foamy, snot, concrete looking creeping flow starts covering everything. I eventually get cornered after running to the door then being pushed into the 'janitors room' and I reach for the water hose knobs and turn it on after picking up the end of it. The water pushes back all of the grim temporary but I glance over and notice the object is a very deep blood red rose with thorns laying untouched by the grim. I eventually get bored and hop into the darkness to wake up.
edit: was just wondering if anyone had an idea what this was about. I've had similar dreams about the same exact rose. I did once have a real life experience of seeing this rose (kinda creepy).