The concept of placing an insect hotel in your garden has become popular in recent times. These homes offer a sanctuary to insects, especially pollinators, and are perhaps a part solution in addressing the declining population of beneficial insects world wide due to climate change, habitat loss, pollution and the abuse of pesticides.
Insects provide many benefits to the ecosystem through pollination, nutrient cycle, and also as a food source for bats and birds. If you are a keen gardener or a nature enthusiast by heart, the chances are that you already have one of these set up around your home. The insect hotels that are available in gardening nurseries and hardware stores, in my opinion, are flimsy in appearance, held together with staples. I wouldn't expect these to be long lasting if exposed to the elements, so I set out to make my own.
Step 1: Targeting Your Guests
I was mainly interested in encouraging the blue banded bee ( an Australian native) to set up home mainly because of their beauty. Many a time I have been woken by these little fellas buzzing around in the garden just after the crack of dawn.
They won't nest in wood hollows, but prefer to burrow into earth banks to nest, so I planned to add a sand mixture to the box frame along with some wood to cater for those insects that do.
Step 2: Materials and Tools
You can easily make your own at next to no cost as I did with mine, using left over timber and materials found lying around the yard.
Timber for the frame to form a box. You could use any old box if one is available.
Some dead branches off trees (not wood that is still green).
Sand and clay
Basic tools like a saw, screw driver plus a few screws to hold the frame together. I also used a router but not really necessary.
Step 3: Making the Frame
I set about cutting up an old timber chest that had been damaged by the weather. This was made from silky oak which was considered a scrap timber (would you believe) when I was a kid.
I made mine a manageable size at 280mm x 350mm and 100mm deep as the sand can make the whole thing quite heavy. The backing board was just plywood, so I used a router to cut the back of the frame so as I could glue the plywood in flush, protecting the edges of the ply where it is most vulnerable to water damage.
I added a piece of timber internally at the apex to give the hook something solid to screw into for support and assembled a picture frame hook at the rear, but you could add any hook to suit your application.
Step 4: Securing the Branches
After assembling the frame, I cut a few lengths of a tree branch about 110mm in length so as they would sit proud of the frame and screwed them to the ply backing. Holes of different diameters were drilled into the wood to suit the various sized tenants .
The whole structure was then coated with a weather proof sealer and allowed it to dry. This was followed by coating all what will be the exposed timber several times with an exterior lacquer to help protect it from the weather.
Step 5: Preparing the Sand Mix
The next step was to fill in around the branch pieces with my sand mix.
Sand on its own would not be practical so we need to add something to help bind it so that it dries into a stable form so that we don't have any cave ins while the bees are burrowing.
To do this, I dug up some clay from the back yard and placed it in a small bucket, covering it with just enough water to cover it completely. Give it a few days or so until the clay becomes a slurry - about the consistency of cream. Strain this through a sieve to remove any small pebbles and roots contained in the mixture, although this step probably isn't necessary.
With the sand in a separate bucket add the clay slurry until you have a moist but a not too runny mixture. I used about 1 part clay to 10 parts sand.
Step 6: Packing in the Sand
The sand mixture was packed in and around the branches using a piece of timber until level with the wooden frame. After trowelling off, holes were then poked into the face of the mix (about 10mm) with a pencil and set aside to dry. Drying time will depend on the climate where you live. Here in the sub tropics mine took about a week.
You most likely have noticed a difference in the layout in some of the photos between the finished product and those while under construction. I made several boxes at the one time, so I apologise for my sloppiness in not taking consistent photos of the same construct.
Step 7: Cleaning Up and Sealing
Once dry, i gave the sand mixture a brush down to clean up and remove any loose particles.
NOTE! It is important that the sand is thoroughly dry, otherwise the lacquer will dry opaque/white, ruining the overall appearance.
The surface was then sprayed with an initial heavy coat to ensure the lacquer penetrated at least a few millimetres. This was followed up by several lighter sprays until there was no more absorption of the lacquer. You can tell this as the sandy surface begins to take on a sheen.
The purpose if this is to further stabilise the sand when the box is in the vertical position and also weather proof the surface and prevent any erosion/scarping from happening.
The final step is to redrill the holes just enough to break through the crust of dried lacquer although probably not necessary as these little guys have been known to burrow holes in soft sandstone.
Step 8: Adding a Roof
To further protect the structure from the elements, I cut a piece of corrugated roofing iron and screwed this on using rubber washers under each screw.
Step 9: Sit Back and Wait
Set aside for a few weeks to allow all the vapours to completely disappear before mounting in the garden.
With my experience, it wasn't too long before the tenants started checking out their new digs and moving in.
Take some time out and enjoy their presence.