Do Gutter Guards Work With Palo Verde and Mesquite Trees?

Do gutter guards work with palo verde and mesquite trees?

Most gutter guard advice is written for oak and maple country, where the problem is a big flat leaf that mats over the gutter in October. That is not the problem in Cave Creek or Desert Hills. The trees that overhang a North Valley roof are palo verde, mesquite, ironwood and the occasional acacia, and what they drop is small, dense and continuous. Whether a guard works here depends on whether it was designed for that.

What actually lands in a Phoenix gutter

It helps to know the calendar, because the litter changes through the year and a guard has to handle all of it.

March to May: palo verde bloom. A mature palo verde drops its yellow blossoms for weeks, and they come down in quantity. Blossoms are small enough to go through a coarse screen and light enough to blow along a gutter and pile at the downspout outlet. They are the reason a screen guard alone is not the whole answer under a palo verde.

All year: leaflets. Palo verde and mesquite leaves are compound, made of leaflets a fraction of an inch long. They shed a few at a time all year and heavily in drought. Leaflets go through anything coarser than fine mesh.

June and July: mesquite pods. Long, and heavy when green. Pods are easy for any guard to shed. They are also the thing that jams a downspout outlet on an unguarded gutter, so they are the strongest argument for a guard if a mesquite is over the roof.

Spring: mesquite catkins. The fuzzy yellow flower spikes. They mat, they hold water, and on a bare gutter they form the dam that everything else piles up behind.

All year: dust and grit. The one nobody writing from a wet climate thinks about. Haboob silt settles onto the roof from spring through fall, and a concrete tile roof sheds fine grit as it weathers. Both end up in the gutter. None of it is stopped by any guard, because it is finer than any screen that would still pass water.

Dust to mud

This is the desert-specific failure and the reason we are honest about what guards do.

From the end of one monsoon to the start of the next, roughly October to June, a gutter collects a season’s worth of silt with almost no rain to move it. The first storm in June or July washes a second load of dust off the roof on top of it. The water goes through, the silt stays, and what is left after the storm is a layer of mud along the bottom of the gutter that dries into something close to the caliche in your yard. It holds moisture against the aluminum, it grows whatever seeds landed in it, and it raises the floor of the gutter until the outlet is half buried.

A guard does not prevent that. What a guard does is keep the pods, catkins and most of the leaflets from combining with the mud into a plug. A guarded gutter under a palo verde needs a rinse; an unguarded one needs digging out. That is the actual value on offer, and it is real, but it is not “never clean your gutters again.”

Which guard styles survive this

The styles we see on Valley houses, and how each one handles the litter above. The gutter guards page covers what we install and how it goes on under tile.

Perforated aluminum screen. A rigid aluminum panel with punched holes, sitting on the gutter under the first course of tile. Sheds pods, catkins and most blossoms. Leaflets and blossoms will get through the larger perforations and ride to the outlet, so it does best paired with an outlet strainer. Handles monsoon rate well because the open area is large. A common choice under mesquite.

Fine mesh. Stainless or aluminum mesh over a frame. Stops leaflets and blossoms as well as the pods. The trade-off in the desert is that fine mesh can blind over: pollen in spring and dust in the dry months settle into the mesh, and when the first monsoon storm hits at an inch an hour, water sheets across the sealed surface and over the edge instead of through. On a 6-inch gutter, which has more width for the water to find its way in, this is manageable with a brush-off before the season. Often the better fit under palo verde where the blossom load is heavy. Which one we put on a given house is on the gutter guards page.

Reverse-curve or surface-tension guards. A solid hood that relies on water clinging to the curve and dropping into a slot. In a gentle rain they work. In a monsoon cell putting an inch on the roof in under an hour, the water is moving too fast to follow the curve and it overshoots. Small blossoms and leaflets also ride the water into the slot. We do not recommend them here.

Foam inserts. A foam wedge that sits in the gutter. Holds silt, bakes in the sun, and is the worst product we know of for a Phoenix gutter. It turns the dust-to-mud problem into a sponge that stays wet. Skip it.

Brush guards. A bottle-brush that sits in the trough. Catches everything, including the silt, and is harder to clean than the bare gutter. Skip it.

Guards and 6-inch gutter

We install 6-inch seamless aluminum as our standard, and guards are one of the reasons it matters. A 6-inch trough has more room under the guard for water to move and for silt to sit without burying the outlet, and its wider opening gives a mesh guard more surface to pass monsoon-rate water before it sheets over. Guards on a 5-inch sectional gutter that already leaks at the joints are money spent on the wrong problem; in that case the gutter is the fix, and downspout and gutter repair covers how we decide between repairing and replacing.

When we would talk you out of guards

No trees over or near the roof. If nothing sheds onto your roof, what lands in the gutter is dust and grit, and a guard does very little for that. Put the money toward a pre-monsoon cleaning instead.

A tree that could be trimmed back. A palo verde limb hanging over the eave puts more in the gutter than a guard can handle. Trim it back off the roof first, then decide whether you still need the guard. Often you do not.

A foam roof with scuppers. Flat-roof homes drain through parapet scuppers, and a screen over a scupper opening is a different product from a gutter guard. Ask us; the answer is usually a simple strainer.

Sectional gutter that is already failing. See above. Guard the new run, not the old one.

What maintenance looks like with guards

Once a year, after the last monsoon storm and before the palo verde blooms, brush or rinse the guard surface and flush the gutter from the top with a hose to move the silt to the downspout. Under heavy trees, a second pass in early June before the first storm. That is a fraction of what an unguarded gutter under a mesquite needs. Our gutter cleaning and maintenance service does the pre-monsoon pass if you would rather not be on a ladder in June.

If you have a palo verde or mesquite over the roof and want to know which guard fits it, we do free estimates and will tell you honestly whether guards are the right spend or whether the tree, the gutter or a cleaning should come first.