Everyone in the Hill Country knows cedar season. Late December through February, Ashe juniper releases enormous quantities of pollen and the whole region suffers through it.
What gets less attention is that the same material is landing on your roof in volume — and it's followed in spring by oak catkins, which are worse for gutters than anything else the year produces.
The Hill Country debris calendar
- December–February: cedar pollen. Fine, dusty, and it gets everywhere. It settles into valleys, works under shingle laps, and combines with limestone dust to form a fine grit that holds moisture.
- March–April: oak catkins. The stringy flower clusters live oaks drop in spring. They're the single worst gutter clogger we deal with — they mat together into a dense plug that water can't move through.
- April–May: oak pollen and leaf drop. Live oaks confuse people by dropping leaves in spring rather than fall. Combined with catkins, this is peak gutter season.
- Summer: limestone dust. Dry conditions and caliche roads produce fine abrasive dust that settles on everything.
- Fall: general leaf drop from deciduous species, plus more oak debris.
Which is to say: there isn't really an off-season for roof debris in the Hill Country. There are just different kinds.
What debris actually does
- Valley clogs. Valleys carry concentrated water volume. A packed valley backs water up sideways, under the shingle laps, where it finds the deck. This is a common origin of leaks that seem to come from nowhere.
- Gutter overflow. A catkin-plugged gutter overflows at the fascia during the first hard spring rain. Water then runs down the fascia, behind the gutter, and into the roof edge and soffit. Fascia rot is an expensive consequence of a cheap problem.
- Moisture retention. Organic debris holds water against the shingle surface long after the rain stops, which accelerates aging and encourages growth.
- Abrasion. Limestone dust and grit act like fine sandpaper under foot traffic and wind, wearing the granule surface.
- Ventilation blockage. Debris packing into soffit vents kills the intake side of your attic ventilation without any visible symptom.
What to actually do, and when
- Late February, after cedar. Rinse or blow the roof surface and valleys. Cedar dust is fine enough to be worth removing before spring rain packs it in.
- Late April or early May, after catkin drop. This is the most important one. Clear gutters and downspouts completely. Check valleys. If you only do one cleanout a year, make it this one.
- Late summer. Check valleys again and confirm soffit vents are clear before autumn.
- Late fall. Final gutter clear before winter, so meltwater has somewhere to go in a freeze. See our freeze prep guide.
Do not pressure wash
It's the instinct, and it's genuinely damaging. Pressure washing strips granules, dramatically shortens shingle life, and typically voids the manufacturer warranty. Use a leaf blower on a dry roof, or a garden hose at normal pressure pointed downslope. Soft-wash services exist for algae specifically.
Do gutter guards help here?
Under live oaks, guards do reduce the workload — but be aware that catkins and cedar pollen are fine enough that cheap mesh guards can clog on the surface, which leaves you with a blocked gutter that's now harder to clean.
Micro-mesh and quality reverse-curve designs handle Hill Country debris better. Either way, guards reduce cleaning frequency rather than eliminating it. Our gutter guide covers sizing and design.
Trees are still worth having
None of this is an argument for cutting down your oaks. It's an argument for keeping limbs trimmed six to ten feet off the roof surface, and for clearing debris on a schedule instead of discovering it as a leak.
Book a free inspection or call (210) 245-4125.
