How to build a bumblebee nest – part 1

All pictures in this post by Renewables At Home – copyright info

As duly noted in my recent ode to bumblebees, bumblebees are my favorite pollinators and deserve a helping hand. So, in an attempt to practice what I preach, I’ve built a bumblebee nest based on an old flower pot. In this post, I’m documenting the process in glorious technicolor and inspiring prose ;-)

It’s a fun project – should be perfect for doing with the kids. If you want other ways to help the bumblebees and other pollinators, take a look at my list of 10 ways to help pollinators survive and thrive.

In order to keep download times manageable, this mini-project will span two posts. In the one you’re reading now, we’ll take a look at how I built the bumblebee nest and prepared for placing it. In the next post, we’ll venture out and find a good location.

Tools and materials

We need a few basic tools and materials for building the nest. Nothing fancy, though:
The materials – impersonating a happy and slightly deranged robot in the picture above – are as follows:

• A terracotta flower pot with a diameter of 20 cm/8 inches (you can use a bigger one, but a smaller one won’t work)
• A matching tray for the pot – this will be a rain cover for the finished nest
• A square of chickenwire (the light gray part of the deranged robot’s nose)
• Some mosquito netting (any fine mesh plastic netting will work)
• Something for fixing the netting to the inside of the flower pot (my mosquito netting came with self adhesive velcro strips, glue will also work)
• A 30 cm. (about a foot) long length of garden hose – this has to have an inside diameter of at least 18 mm. (0.71 inches)
• A nail slightly longer than the garden hose’s outside diameter

Next, the tools list:

• Tin shears (or something else for cutting chicken wire)
• Glue
• Pair of pliers
• Scissors
• A drill with a reasonably large masonry drill bit (or something else that will pierce terracotta without breaking it)
• A hammer (not pictured)
• An awl (not pictured) or some other sharp tool for making holes through the garden hose

Bumblebee nest ventilation

Like most other animals, bumblebees don’t get much done if they’re too hot.

To make sure the nest doesn’t overheat, we have to provide at least two, preferrably three ventilation holes. Most terracotta flower pots will already have one in the bottom:
We don’t have to make two more that big – as long as air can pass easily through the holes, we’re okay.

So, grab your drill and make two holes on opposite sides of the flower pot. Keep them near the bottom of the pot (this will be the top of the nest), about 1,25 centimeters (half an inch) up.

Keep the flower pot steady while you drill. Start out carefully – the drill will slip easily at first. Don’t push hard; it increases the chances of the pot cracking up. Let the drill bit do its thing. Oh, and turn any hammer action your drill might have off.

Ants begone!

Right, holes are done. We can’t leave them as is, though. If any roving ants pass by, they’ll enter the nest through the holes and wreak havoc on the bumblebee colony.

This is where the mosquito netting comes in. Provided it’s finely meshed, it will let air through but block ants.

Cut out a few pieces of netting and fix them to the inside of the pot, covering the holes completely. I used the velcro strips that came with my mosquito netting and a few drops of glue for this, but using just glue on its own should work fine, too.
Hey presto, ants are kept out! Plus it makes the flower pot look kind of like a loudspeaker ;-D

Chickenwire cradle

Next up is a cradle for the nesting material we’ll put in the nest later.

It’s important that the nesting material doesn’t get wet, or mold and other bumblebee-bothering unpleasantness may show up. Keeping the nesting material above ground with a chickenwire cradle is a good way to keep things dry.

Cut out a square of chickenwire that will almost cover the wide end of the flower pot (see photo below).
Use the pliers to bend the corners of the square. The corners should work as feet for the cradle. Also bend any sharp wire points inwards, below the cradle. I don’t know if bumblebees are particularly vulnerable to sharp points, but we might as well be careful.
When you’re done bending the corners, set the cradle down and make a dimple in the middle. The end product should look something like this:

The nest entrance

Bumblebees aren’t the most demanding in terms of grand entryways. As long as it’s an obvious tunnel that ends somewhere dry and cozy, they’re happy. Which means our length of garden hose fits the requirements quite nicely :-)

To make sure the nest and the entrance tunnel is kept dry when it rains, we have to make some drainage holes in the hose.

Make several holes near the middle of the hose length, along the outside curve.

Run a bit of water through the hose to make sure the holes are big enough to work as drainage.
The final step before finding somewhere to place the bumblebee nest, is keeping another unwanted guest out: Slugs.

Slugs won’t attack or harass the bumblebees directly, but they might crawl into the nest’s entrance and die. The bumblebees won’t be able to get it out of the way.

To keep slugs out, we run the nail through the garden hose, close to one of the ends. Make sure you run it through slightly off-center. This should work as a discouraging roadblock for slugs, while still letting the bumblebees pass.

The great outdoors

The bumblebee nest parts should now be ready to be taken outside and set up in a good location.

In the picture below, the parts for my nest look happy at the prospects of getting some fresh air :-D
That’s it for this part – continue on to How to build a bumblebee nest – part 2 to see how we find a good site for our nest.

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This post was tagged with: bumble bees, bumblebee nesting boxes, bumblebee nesting sites, bumblebee nests, bumblebees, pollinators

Related posts:

1. How to build a bumblebee nest – part 2
2. I like bumblebees
3. 10 ways to help pollinators survive and thrive
4. Two more R’s: Refuse and Repurpose