Hi Theo,

It's great you are interested in making your garden a nice home for bees. One of the best things you can do is provide habitat for pollinators. Alaska is home to over 100 species of native bees and some of them have some specific requirements, but here are some general considerations when planting or making habitat for pollinators: 

-Plant a variety of flowers of different shapes: different pollinators have different shapes and sizes of mouthparts which can impact which flowers they are able to collect pollen and nectar from
-Plant flowers that bloom at different times of the season: different pollinators emerge at different times throughout the summer so try to always have flowers in bloom
-Plant a variety of flowers of different colors: some pollinators have preferences for specific colors
-Incorporate native flowers into your garden: some pollinators prefer certain species of native plants
-Don't clean up the garden too much: some of our stem-nesting bees may have larvae nesting inside last year's hollow or pithy stems, leave those stems standing to allow any young bees to emerge the next summer (link to some more information about this: https://xerces.org/sites/default/files/publications/22-005_01_web-press.pdf )
-Leave some areas of bare, undisturbed soil. Many of our native solitary bees are soil-nesters.
-Let your herbs flower: many of our herbs have flowers that are attractive to pollinators, such as chives, basil, cilantro, dill, mint, thyme, rosemary, and sage
-Manage invasive plants on your property: many invasive plants are excellent spreaders that outcompete other flowering plants, reducing floral diversity. Floral diversity is key for attracting and supporting a wide variety of our wonderful Alaska pollinators.

As far as creating the nesting homes for bees, these can be neat tools for watching pollinators up close in your garden. They are not a replacement for habitat but can be a nice supplement. These homes target stem-nesting solitary bees which is estimated to be about 20% of solitary bee species. I highly recommend building your own rather than purchasing one from the store. The store-bought ones are very shallow whereas many bees prefer a longer nesting tunnel. The short tunnel can be an issue for some species as many species lay the female young near the back of the tunnel and the males near the front, so if the tunnel is too short they may make too many males which isn't ideal. There are a couple really great resources for making your own though, one is this publication from University of Nebraska Lincoln: https://entomology.unl.edu/scilit/Creating%20a%20Solitary%20Bee%20Hotel.pdf

And the other is this guide by Colin Purrington: https://colinpurrington.com/2019/05/guide-to-diy-mason-bee-houses/

Hope this helps and you have fun building some bee homes for your garden!