What causes green algae on vinyl siding in Hudsonville?

Green algae thrives on the shaded, north-facing sides of West Michigan homes where moisture lingers. Lake-effect humidity, tree cover and afternoon shade combine to create perfect growing conditions. It's not just cosmetic — left untreated, algae and the mildew that follows can damage siding over time.

What are the black streaks running down my siding?

Those vertical black streaks are typically Gloeocapsa magma — a hardy cyanobacteria — combined with mildew. They're most common under gutters and on north-facing walls. Pressure alone won't remove them; they need a soft-wash solution that kills the organism at the root.

Is soft washing safe for vinyl siding?

Yes. Soft washing uses low pressure (under 500 PSI — about the strength of a garden hose) combined with biodegradable cleaning agents. It's the method siding manufacturers themselves recommend. High-pressure washing, by contrast, can crack vinyl, force water behind panels, and void siding warranties.

How much does a house wash cost in Hudsonville?

Most 2,000–2,800 sqft single-story and 1.5-story homes in Hudsonville and the surrounding areas fall between $325 and $550 for a full soft-wash house wash. Two-story homes and homes with heavy algae or stain bands typically run $475–$750. Request a free quote for an exact number.

Soft Wash Vinyl Siding & Algae Removal in Hudsonville MI

Short answer: Green algae, black streaks and that overall gray film on West Michigan vinyl siding are all living organisms, not just dirt. They need a soft wash — low pressure plus a biodegradable cleaning agent that kills them at the root — not high-PSI blasting that just cracks siding and grows back in months.

If your Hudsonville home is showing green on the shady side, black streaks under the gutters, or a general dingy gray on every wall, you've got the three most common exterior siding problems in West Michigan. The fix isn't more pressure — it's the right chemistry applied gently. Here's what each one is, and how a soft-wash service handles it.

The 3 things growing on your siding

1. Green algae (the shady-side problem)

That green tint on the north and east sides of your home is algae — a living organism that feeds on moisture and the trace minerals in vinyl. West Michigan's lake-effect humidity plus mature tree cover make Hudsonville, Jenison and Grandville homes especially prone. Pressure-washing knocks it off temporarily, but spores embedded in the siding texture grow back within months. A soft-wash solution kills the organism so regrowth takes years, not weeks.

2. Black streaks (the gutter-line problem)

Vertical black streaks running down from your gutters or under window sills are usually Gloeocapsa magma — a hardy cyanobacteria — mixed with mildew. It's the same organism that causes black streaks on asphalt shingle roofs. Like algae, the staining is biological, not dirt, so it requires a soft-wash treatment to actually remove rather than smear.

3. Gray film (the everywhere problem)

The overall dinginess most homes pick up over 2–3 years is a slow buildup of pollen, road dust, mildew, and pollution settling on the siding texture. It's so gradual you don't notice until you see the bright clean strip behind a planter you've just moved. A full soft-wash house wash strips it off in a single visit.

Why soft wash, not pressure wash, on vinyl

Vinyl is designed to flex. High-PSI water can crack it, especially on older siding that's become brittle in West Michigan winters.
Pressure forces water behind the panels. Water in the wall cavity leads to mold, rotted sheathing and insulation damage.
Pressure doesn't kill biology. Algae and mildew regrow from spores left in the siding texture within months. Soft-wash solutions actually kill the organism.
Most vinyl manufacturers' warranties specifically call for low-pressure cleaning with a biodegradable solution.

The full breakdown is in our companion guide: Soft Wash vs Pressure Washing for Vinyl Siding.

What a PurePro soft-wash house wash includes

Full perimeter walk to identify algae, streaks, hornet nests and any siding damage to flag.
Plants and landscaping pre-rinsed and protected before cleaning agents are applied.
Biodegradable soft-wash solution applied at low pressure to dwell and kill biology.
Low-pressure rinse from top down with clean water.
Final plant rinse to neutralize any drift on landscaping.
Optional add-ons: gutter face brightening, walkway and driveway pressure wash, deck cleaning.

Bundle with a window cleaning

About 70% of our Hudsonville house-wash customers add a window cleaning to the same visit. The crew is already on-site with water and ladders, your windows just got soaked from the wash anyway, and bundling typically saves a chunk off booking them separately. See our spring exterior cleaning checklist for the full top-down order we recommend.

We cover Hudsonville, Allendale, Jenison, Grandville and Georgetown Township with same-week availability through spring and summer. Request a free quote and we'll send a real number within 24 hours.