Would Malarkey shingles survive a solar-powered zombie apocalypse?

You nailed it - moss is way more than just ugly in the Pacific Northwest. I learned the hard way too, letting it go on my last place and ended up with curling shingles and a soggy mess underneath. I’m curious though, has anyone tried those spray-on moss killers that claim to be “eco-friendly”? I’ve heard mixed things, but if they actually work without wrecking the panels or runoff into the garden, I might give them a shot.

I've tried a couple of those eco-friendly moss sprays and honestly, results were mixed. One brand barely touched the moss, but another worked after a few weeks - just had to be patient. My main concern’s always been if it’ll mess up the solar panel frames or drip down onto my veggie beds. Has anyone had issues with stains or residue on panels after using these sprays?

- Seen similar results with moss sprays - some just don’t cut it, especially on older roofs or in damp climates.
- I’ve noticed a few brands can leave a chalky residue if you overspray, but nothing that stuck around after a good rain.
- Panels themselves seem fine, but I’d watch for runoff if your veggie beds are right below. Had a client with tomatoes get some white spots, but they washed off.
- If you’re worried about stains on frames, maybe try a test patch first? Sometimes the eco stuff is gentler, but not always perfect.
- Patience is key...but yeah, not all sprays are created equal.

I get what you’re saying about the sprays, but I’ve actually had the opposite issue with runoff - especially after a heavy rain. Even if the residue washes off panels, it can still leave streaks on lighter shingles or metal flashing. Maybe it’s just my area (super rainy, lots of moss), but I’ve seen some stains stick around longer than expected. Also, not sure all “eco” sprays are as gentle as they claim...had one that left a weird film on composite shingles for weeks. Just something to watch for if you’re picky about how your roof looks.

Even if the residue washes off panels, it can still leave streaks on lighter shingles or metal flashing.

That’s been my experience too, especially with lighter colors and after a big downpour. Here’s what I’ve tried: first, I always check the label for any mention of “safe for composite” or “no residue,” but honestly, that’s hit or miss. If you’re picky about appearance, I’d suggest testing any new spray on a small, hidden patch first. Also, after application, I’ll hose down the area lightly to dilute runoff - seems to help with streaks. For moss, manual removal (scraper + soft brush) is tedious but avoids weird films. Not perfect, but it keeps things looking decent between rainy spells.