Last spring, I watched my neighbor, let’s call him Dave, drag out his pressure washer for what had to be the fifth time that year. Hoodie on, hose spraying like a fireman in training, he looked determined. Or maybe annoyed. Either way, the man was committed. A week later, the moss was back, like it never left.
That’s Oregon for you.
Oregon doesn’t play fair
If you live here, you know the drill. Rain, followed by more rain. Then, just when things start to dry out, a surprise drizzle. And with all that moisture comes an aggressive combo of moss, algae, and grime that loves settling on your concrete like it owns the place.
Here’s where it gets interesting: pressure washing too often can actually damage your driveway, especially if it’s older or not properly sealed. But not washing enough? That can lead to permanent staining and slippery surfaces that turn walking to the mailbox into a low-stakes stunt show.
So what’s the sweet spot?
The once-a-year rule
Most Oregon homeowners can safely pressure wash their driveways once a year, usually in late spring or early summer, after the rainy season but before the heat sets in. That’s your window.
But here’s the thing: Oregon isn’t one-size-fits-all. If your driveway sits in full sun, you might stretch it to every 18 months. But if you’re surrounded by trees, or your driveway’s on the north side of the house where moss throws parties, you might need to do it twice a year. Just… maybe not like Dave.
You don’t want to blast it every month. Concrete is tough, but it’s not indestructible. High-pressure water can wear down the surface, especially over time. That’s when cracks show up and the driveway starts looking like it’s been through a few too many winters. Which, frankly, it has.
What’s growing on your driveway?
Let’s take a quick detour into the weird world of driveway biology.
In Oregon, the biggest culprits are:
- Moss – likes shade, traps moisture, turns slick when wet
- Algae – that greenish film that creeps across the surface
- Lichen – the stubborn gray stuff that looks like it’s part of the concrete
All of these thrive in the Pacific Northwest’s damp conditions. And they’re not just ugly; they can actually make the surface dangerous. One slip on moss, and you’re Googling “rotator cuff surgery recovery time.”
A pressure washer isn’t a magic wand
This is where a lot of folks go wrong. They think pressure washing is a cure-all. Blast it, rinse it, done.
But it’s not just about spraying. To really protect your driveway and your time, you need to combine pressure washing with preventive care. That means:
- Trimming back trees to reduce shade and let things dry faster
- Sweeping regularly to keep debris from collecting moisture
- Using a moss killer or concrete-safe cleaner once or twice a year
- Sealing your driveway every few years to help repel moisture
If that sounds like overkill, it’s not. Think of it like flossing. Annoying, but worth it.
Quick tip: rent, don’t buy (unless you’re Dave)
Unless you’re using your pressure washer for more than just the driveway, like siding, decks, fences, etc., you probably don’t need to own one.
Home Depot, Sunbelt Rentals, and even some neighborhood hardware stores will let you rent one for the day. It’s cheaper, and you avoid the whole “where do I store this dripping beast of a machine” dilemma.
Also, for the record: electric pressure washers are fine for light cleaning. But if your driveway hasn’t been touched in two years and has moss colonies with zip codes? Go gas-powered. Just be careful. Always start on the lowest pressure setting and work your way up.
So, how often should you pressure wash your driveway in Oregon?
Let’s recap without sounding like a brochure:
- Once a year works for most Oregon driveways
- Twice a year if you’ve got heavy shade, moss, or high traffic
- Every 18 months if your driveway lives a chill, low-moss life
And in between? Just stay on top of the little things. Keep it swept. Kill moss early. Rinse off dirt before it settles in like a bad habit.
Final thought
You don’t need to become your neighborhood’s Dave. But you also don’t want your driveway looking like a biology experiment. Find that middle ground—pressure wash once a year, maybe twice, and stay ahead of the moss.
Thinking it’s time to schedule a cleaning? Reach out to a local pressure washing service in Oregon and get a quote—it’s often cheaper (and faster) than hauling out the gear yourself.
