Fall Leaf Season in St. Louis: Keeping Gutters Clear
The trouble with fall in St. Louis is that it isn't one leaf drop. It's three or four, weeks apart, from different trees, and a gutter cleaned at the wrong point in the sequence is full again before the invoice is paid. Here is the calendar as it actually runs on St. Louis streets.
The St. Louis leaf calendar
| Tree | Where you find it | Drops | What ends up in the gutter |
|---|---|---|---|
| Silver maple | 1950s–70s subdivisions everywhere | Helicopters in May; leaves early October | Seeds lodge in downspouts; leaves are light |
| Sycamore | Creek lots, older streets, Forest Park edges | Mid-to-late October, in a two-week rush | Huge leaves that mat, plus bark in winter and seed balls in spring |
| Sweetgum | Postwar city and county streets | Late October–November | Leaves, then spiked balls that roll into gutters through winter |
| Pin oak | Kirkwood, Webster Groves, University City, Clayton | Late November into December, some hold until spring | Small, stiff leaves that pack hard; acorns and caps |
| White and red oak | Older lots county-wide | November | Leaves and acorns |
| Cottonwood, elm | River bottoms, Chesterfield valley, Florissant | October | Small leaves and fluff |
Two things follow from that table. First, anyone under a sycamore needs a gutter check by the end of October, because those leaves fill a 5-inch gutter in a week and a run full of wet sycamore leaves weighs enough to pull spikes. Second, anyone under pin oaks should not pay for a cleaning before December, because the oaks haven't started.
The right dates
- Early to mid-October: under sycamores and maples, a first clean-out, or at least a look. This is also the last comfortable window to fit guards.
- First dry week of December: the main fall cleaning for most of the county, after the oaks have let go and before the first hard freeze locks everything in place. If the freeze comes early, wet leaves left in the run become a frozen plug until March.
- Late May: the spring cleaning, after the maple seeds and the sycamore bark.
A gutter that's cleaned in early November on Argonne Drive in Kirkwood, under pin oaks, will be full by Thanksgiving. One cleaning in December beats two.
What a full gutter does in November
It isn't just overflow. Leaves hold water, water sits, and the first freeze — usually late November — turns the run into a bar of ice with leaves in it. Ice expands in the corner seams and opens them. The weight bows the run between hangers and backs the spikes out. When it thaws in a January warm spell, the corners drip and the pitch is gone. A lot of the "winter damage" found in March started as a gutter that went into December full.
Signs leaves in gutters are already causing trouble
You can usually tell from the yard that a gutter has filled up, even before it overflows.
- Debris sticking up over the edge of the gutter, or a dark line of wet debris visible from the street.
- Water spilling over the front in an ordinary rain, often at a corner or the far end from the downspout.
- A downspout that goes quiet during rain. If you can't hear water running inside it, the elbow is probably plugged.
- Sprouts in the gutter — maple seedlings and grass grow in one that has held wet debris too long.
- A run that has started to sag under the weight.
Any of those is a sign to clean now rather than wait for the planned date.
Valleys, dormers and low roofs
Leaves don't only collect in the gutter. They pile up in roof valleys, behind chimneys and on low porch or garage roofs, then wash into the gutter in the next storm as a thick plug. On many older city and inner-suburb homes, a low back porch roof under a big tree collects more debris than the main gutter. Have those spots checked during a cleaning. A wet pile sitting in a valley also holds water against the shingles, which makes it a roofing problem too.
What to do with the debris
Gutter debris is wet, heavy and full of grit from the shingles. Bag it or add it to a compost pile rather than leaving it in the flower beds next to the house, where it holds water against the foundation. Some cities offer fall leaf collection or yard-waste pickup, and the rules differ from place to place, so check with yours. Don't wash gutter debris into the street drain.
Fall mistakes to avoid
- Blowing the gutter out from the ground. Leaf-blower attachments move dry leaves but leave wet mats and grit behind, and they rarely clear the downspout.
- Cleaning once, in early November, under oaks. It's often too early.
- Forgetting the downspouts. A clean gutter with a plugged downspout still overflows.
- Leaning the ladder on the gutter. That's how a cleaning turns into a repair.
Cleaning it yourself
Single story, a stable ladder, someone at the bottom: fine. Scoop into a bucket hooked to the ladder, not onto the lawn. Then flush every downspout from the top and check that water comes out the bottom — a downspout plugged with helicopters and one sycamore leaf will back up a clean gutter. Stop if the ladder would have to rest on the gutter, if you're reaching sideways more than an arm's length, or if it's two stories. Two-story gutter cleaning is $180–$300 here and it includes a look at the hangers and corners, which is worth more than the scoop.
Guards, by tree
Guards don't remove the maintenance; they change it from scooping to sweeping. Which one depends on the tree above the run.
- Sycamore and sweetgum: a wide-perforation aluminum screen keeps the big leaves out for $5–$9 a foot. Seed balls sit on top and blow off. Cheap and effective.
- Pin oak: the small leaves pack into anything with a gap. Stainless micro-mesh at $10–$18 a foot is the only guard that stays clear, and it still wants a broom pass in December.
- Silver maple: helicopters go through every screen and lodge in downspouts. Micro-mesh or nothing.
- Cottonwood: fluff mats on mesh and rinses off with a hose. Screen lets it through.
Reverse-curve guards — the solid hood — collect sycamore leaves on the nose and grow icicles off it in January. They're a poor match for St. Louis trees. The guards page has prices and the ice question, and what gutter guards are worth it under St. Louis trees goes deeper on each type.
The short version
Look at what's over the roof, not the calendar on the wall. Sycamore: October. Oak: December. Both: October and December, or guards. And every visit, flush the downspouts.
Common questions
Is it bad to leave leaves in gutters over winter?
Yes. Wet leaves hold water, the water freezes, and the weight and expansion strain the hangers and open the corner seams. In spring the rotting mat can also feed rust on steel gutters and rot on the fascia. One cleaning after the last leaves fall, before the hard freeze, avoids most of it.
How can I tell when my trees are done dropping?
Look at the branches, not the ground. When most of the canopy over the roof is bare, the bulk of the load is down. Pin oaks are the exception: they can hold brown leaves into winter, so judge them by how many leaves are still falling each week rather than by bare branches.
Should I hire a cleaning before or after Thanksgiving?
Under sycamores and maples, before is usually fine, because most of their load is down by early November. Under pin oaks, after is better, ideally the first dry week of December. If you have both kinds of tree, plan on two visits or ask about guards.
Are leaf blowers safe to use on the roof?
Not for most homeowners. Standing on a roof with a blower is a fall risk, and the air can push debris under shingles or down into downspouts. From a ladder on a single story, a blower can clear dry leaves from guards, but wet mats still need a scoop.
Need gutter work in St. Louis?
Call for a free estimate. Mon–Sat 7am–7pm.