This instructable will show you how to build a bee box with a flower planting area. If you lived in an apartment you could even 3d print a small version.

Want to help out the bees but don't want to built a bee box then check out-
http://sos-bees.org/

Step 1: Materials and Tools

Some wood that's large enough to drill holes in
Some wood for the roof such as plywood
A plant pot or some wood to make one
Nails, glue or screws to hold it together
Drill
Soil and flowers
And a saw

Step 2: Step 1

Assemble the wood like so and secure in place.

Step 3: Step 2

Cut out a piece of wood so that your plant pot will fit in. To make a basic plant pot cut five identical pieces of wood and join them together.Next attach it to the underside of the roof with nails or glue or screws.

Step 4: Drilling the Bee Holes

I think you have to drill them 2mm-10mm but different sizes of bees like different sized hole so best to have quite variety of sizes.

Step 5: Finished

the hole add a plant to your plant pot (if possible one that will attract bees) and hang it up, I did this by drilling two hole completely through it, placing nails through the hole and nailing it to a wooden post.