So, you’ve got a beautiful wooden bench—maybe it’s a cedar one on your porch or a reclaimed pine bench in the garden—and you’ve noticed some tiny holes or sawdust near the legs. That’s the calling card of wood-boring insects. Protecting your bench from these critters isn’t just about aesthetics; it’s about making sure the piece lasts for years. After a lot of trial and error, and some advice from carpenters and woodworkers, I’ve found that the best way to protect wooden benches from insect damage is a layered strategy that starts before the wood ever sees a bug.
First, choose your wood type wisely. If you’re building or buying a bench, go for naturally insect-resistant species like cedar, redwood, or teak. These woods contain natural oils that repel bugs. But if you’re stuck with pine or fir, don’t worry—you just need to be more proactive.
The absolute best first line of defense is a good wood sealer or preservative. I highly recommend using a borate-based treatment. Borates (like Timbor or Bora-Care) are a natural salt that penetrates deep into the wood, then crystallizes and kills any insects that try to eat it. The best part? It’s safe for pets and people once it dries. You can apply it with a sprayer or brush before you assemble the bench. Let it soak in for at least 24 hours in a dry spot.
After that, apply a high-quality exterior wood finish. A spar urethane or marine-grade varnish creates a hard, water-resistant shell that not only prevents rot but also stops insects from getting a foothold. Make sure you seal every crack, end grain, and joint—that’s where bugs like to sneak in. I usually do two to three coats, sanding lightly between each one.
Another secret weapon is using a natural insect-repelling oil. Tung oil or Danish oil mixed with a few drops of neem oil or citronella oil can be a great, low-toxicity option. The smell fades quickly but bugs hate it. Apply it once a year as part of your maintenance routine.
Don’t forget about the ground contact area. If your bench legs sit directly on soil or grass, insects (especially termites) will use that as a highway. Placing metal or plastic feet pads on the legs, or setting the bench on a concrete or gravel base, makes a huge difference. Even a simple layer of crushed stone under the bench can reduce moisture and pest access.
Finally, practice regular inspection and cleaning. Once every season, flip the bench over and check for small holes, frass (that’s bug poop, looks like sawdust), or soft spots. Wipe the surface with a slightly damp cloth to remove pollen and dirt that can attract beetles. And if you ever find an active infestation, treat the spot immediately with a targeted insecticidal spray or inject borate powder directly into the holes.
So, in a nutshell: pick the right wood, prep it with borates, seal it with a tough finish, protect the legs from ground contact, and check it regularly. That’s the honest, practical way to keep your wooden bench looking great and bug-free for decades.