" It makes sense that beauty brands, given how many of them rely on honey or beeswax in their potions and balms, have started to get involved. And the best part? Helping bees can now be as simple as buying a face cream. (But you should also support local beekeepers and maybe plant some flowers, too, if you want to make an even bigger impact.) " Is so true! Both my organic facial cream and lotion have honey. Here in The Netherlands, Greenpeace promotes it to adopt bees for as low as 5 to 15 euro to support them for a year and you get to have a pack of flowers bees love and they support the beekeepers. Almost every house with a garden have a bee hotel as well. I do and I saw two wild bees alternately planting larvae and sealing the bamboo holes with mud before. I thought I'll hear them buzzing in July but they stayed sealed. 
What could be wrong? I now have two of them hoping they'd be full next year.
There's more bees this year than last year but I wonder do you think the larvae on the brown bee hotel would actually hatch? Perhaps next year or should I start unclogging the holes?
Don't unclog the holes, be patient. I suspect the bees put some eggs into the tube then mud then more eggs and more mud. They bees will most likely emerge next spring when things warm up. I am not familiar with the brown bee, but Mason bees (which people will keep in those same type of tubes) here in the US emerge in spring and are active for only a short period (6-8 weeks). The tubes sit idle the rest of the time. Don't despair.
@jwaser, I see .. but wouldn't it be frozen in winter? the bees must have planted two larvae each hole i suppose. I watched them do it in Spring. They looked like honey bees but maybe you are right - they must be mason bees. Anyway, I'll let it be like that and perhaps cover it to keep it warm in winter
Thank you. I hope you fix your featured posts