In honor of National Pollinator Week (June 17-23, so, I’m a little late…), I’m pulling out the drill and building my first native bee house for the garden.
We’ve all heard of honeybees and bumblebees, but the real drivers of pollination in most gardens are the smaller native bees — mason bees, leaf-cutting bees and others. Of those hard-working natives, roughly 30% nest in holes that beetles, grubs and other beasties have drilled and then abandoned in dead wood.
Leave a section of log in your garden long enough, and you will be able to watch this all unfold. First, the wood-boring bugs will drill their homes in the log. Then, once they’ve moved on — perhaps a year later — the little native bees will take over those holes. If you ever find a small hole that has been plugged with mud or bits of leaves, you’ve found yourself a native bee nest. Do a little dance of joy: those baby bees in that nest will be next year’s pollinators.
While it’s perfectly acceptable to let nature and wood-boring bugs set the pace in your garden, you can speed things along by adding a bee house for those wood-dwelling pollinators. This is easier than building a bird house. Much easier.
Here’s what you need:
- Scrap wood: make sure your wood is untreated, and is at least six inches deep.
- Drill bits: grab several, ranging in size from 3/32-inch to 3/8-inch, and long enough to drill a 5-to-6-inch deep hole.
- round file
- tape (optional)
- measuring tape (optional)
Do you have everything gathered? Great! You’re nearly done. All you need to do is drill those holes and prep them for bees.
First, the holes: For best results, drill those holes so they are at least 3/4 of an inch apart when measured on center. You can space them further apart if you life, but the bees will complain if you crowd them any closer. Now, if you’re the
perfectionist detail-oriented type, you can measure this out and create an orderly grid for your holes.
You could even create a template to guide the placement of your holes if you like.
Or, you can free-form:
If you want to maximize the number of bee holes in a piece of wood, you will want to measure it out and drill all your holes at 3/4-inch distances. I prefer the free-form approach, mostly because it saves time. I don’t even bother measuring the distances between the holes. Instead, I use my thumb, which measures about an inch from thumb-tip to that first knuckle — the perfect measuring guide for laying out a bee house. Chances are you can do the same.
While drilling, remember to mix up the hole sizes. There are many different species of hole-nesting native bees, and they come in various sizes. The smaller bees want to lay their eggs in smaller holes, while the larger bees prefer to lay their eggs in larger holes. For best results, drill holes that are 1/4-inch or wider to a depth of 5-6 inches. For holes smaller then 1/4-inch, a 3-4 inch depth is best.
In order to ensure you drill your holes to the proper depth, you can choose to mark your drill bit with a small piece of tape.
Note: This project works best with long-shanked drill bits.
Now, start drilling. I prefer to start with the larger holes, and then work down in size with the drill bits. For this particular bee house — drilled into a section of log — I am drilling several different sized holes, between 3/32-inch to 3/8-inch in diameter, and roughly 3-5 inches deep. Because the bees want their nesting holes to be as smooth as possible, I am using a Forstner style drill bit to start the holes, and then am using a spade bit or brad-point bit of the same size to finish each holes. I’m doing this because the Forstner bits tend to drill very smooth holes, but aren’t long enough to reach the 3-6 inches these holes require. You can skip the Forstner bits if you prefer; a round file will also work to smooth out the holes you drill.
Again, I just use my thumb as a guide for hole placement. This is not the most space-efficient way to do this, but it’s awfully time efficient. Basically, you just drill your first hole, and go from there.
Couple things to keep in mind:
- Your drill bits will get very hot. Don’t touch them. In fact, it’s best to let your drill rest for a few minutes after every few holes.
- When drilling, pull your drill bit out of the hole a few times to help clear the saw dust. Do this while the bit is still running.
- If possible, clamp your piece of wood down to something secure. Or, wedge it against something. If your drill bit binds on a wood knot, that piece of wood can twist around and smack you hard.
- Sometimes drill bits break. If this happens, it’s ok to curse and whine for a moment. Then, just move on to the next size hole.
Once the holes are drilled, I use the round file to smooth the holes. I simply insert the file into each hole and twist and push to rub any splinter or wood spurs off the side of the drilled holes.
And, we’re done!
Depending upon the kind of wood you used, you may want to use screws, nails or some other manner of attachment to hold your bee house snug to a fence or other support. In this case, since I drilled these holes directly into a log round, I simply set the finished bee house on the edge of my new garden space, and I declare the project complete.