Algae and Mildew Removal on Hawthorne's Shady Walls

Why one side of the house turns green

Walk around a home near Lochloosa, Johnson Lake or Little Orange Creek and the pattern is usually obvious: the south side looks fine, while the north wall, the eaves under big trees and the side facing the lake carry a green or black film. Those surfaces get little direct sun, dry slowly after rain and morning dew, and collect the organic dust and pollen that algae feed on. In this part of Alachua County, mildew can show up within a year or two of a fresh paint job on the wrong wall.

Pressure washing in Hawthorne, FL for those walls is really a cleaning-and-treatment job. Water alone moves the growth around; it does not kill it. Lake homes also pick up a fine film of insect residue and spider webbing near exterior lights, which a proper cleaner lifts far better than plain water.

How we wash shaded walls

• Wet down landscaping along the wall and cover delicate plants.
• Apply a cleaning solution at low pressure from the bottom up, so it does not streak.
• Allow dwell time for the solution to break down algae and mildew roots.
• Rinse from the top down with low pressure, including eaves, soffits and the faces of gutters.
• Rinse plants again and check corners, window frames and light fixtures by hand.

Surfaces that need extra care

Older wood siding, painted trim and screen porches are common around Downtown Hawthorne and the lake communities. They are cleaned at the gentlest settings, because high pressure can force water behind boards and peel weak paint. Vinyl siding gets a similar soft wash approach, angled downward so water does not go up behind the laps. Stucco and block take a bit more, but still nothing close to what concrete flatwork gets.

Window screens, light fixtures and electrical boxes are rinsed carefully rather than sprayed directly. Gutters overflowing onto a wall are often the hidden reason a single section stays green, so we mention any we notice during the wash.

Making the clean last longer

Shade will always invite regrowth, but a few habits slow it down. Trimming branches that overhang the roof lets in light and air. Keeping shrubs a foot or more off the siding helps walls dry. Adjusting sprinklers so they do not wet the house removes a constant water source. Many owners in shaded settings schedule house washing once a year, often in late spring after pollen and before summer humidity peaks.

If mildew keeps coming back through the paint itself, or the paint is peeling where the growth was, the coating may be at the end of its life. Our Hawthorne exterior painting page explains wood siding repair and repainting, and this article on Florida weather covers why humidity is so hard on exteriors.