On the internet you need visitors and hits. And for that, even if the content is useful (blog), if it stops getting updated the search engines will pretty much bury it.
So a blog may not be what you need. Maybe a forum, since people will keep posting there as long as you've built the right community.
In theory the nature gives a lot for free, but in reality it doesn't do it at a constant rate and imho this makes agriculture risky.
There can be great years and there can be years with extreme drought, or floods, or hail, or whatever and the business has expenses and no income.
Zootechny/growing animals can be risky because of diseases (I've heard of pig farms where 30k animals had to be burned).
If there are ways to properly overcome (or insure against) all of these then yes, it can be a good option.