Food52 is no joke my favorite website. I must email my wife 10x per day with ideas from the site. I wonder if there is anything close to this for gardens / gardening?
What a great question. There must be. I can't wait to see the answers.
For user-community Q&A, the Gardenweb forums are probably the closest thing, although they don't have anything like the feature articles you see here.
The forums vary a lot in terms of activity and quality.
Mike McGrath’s “You Bet Your Garden” NPR radio show is a wealth of information (former editor of Organic Gardening magazine). He covers trees, shrubs, lawns, vegetables, annuals, perennials, pests… everything. A wealth of information.
As far as I know, there isn’t online community like Food52’s, but the web site contains very useful information. Click “Ways to Listen” toward top right of page.
You might also want to check with your local agricultural Extension Program (usually affiliated with a nearby university or college) to see if they have an online user community. Always helpful to have resources who are familiar with local species and growing conditions. http://www.csrees.usda.gov/qlinks/extension.html
If you have a mobile device, I'd recommend downloading the Flipboard app (you pick topics you're interested in and it essentially creates a "magazine" for you),which is free and a great way to discover new sources for pretty much any topic - I actually found Food52 through their Food section!! I have Gardening on my Flipboard too, and have found that the site Gardenista often has interesting articles.
Don't know where you live and these are my favorite Northwest sites. http://www.nwedible.com http://swansonsnurseryblog.com And I always google best garden blogs and check things out.