Best way to show search results for different content types

On a website that has different types of content on the same topic, how should this information be displayed after a user searches. Let's say a site's topic is "trees" and the content types are as follows:

  • Editorial Content: timeless content that is about a broad topic (i.e. an article about tree species).
  • User Content: user generated content about one specific thing (i.e. information about a specific tree nursery near London).
  • Events: time sensitive user generated content about a specific event (i.e. a tree growing course in Scotland in May).
  • Blog Posts: time sensitive content that is about a broad topic (i.e. a review of the state of Britain's forests in 2014)

There is a broad range of content but it is conceivable that a user would want to search through all of it. A user may want to search for "Pine Trees" for example. This should return any content that is relevant which may be any of the types mentioned above.

The challenges are:

  1. How to communicate what type of content something is.
  2. How to order the content.
  3. How to display a range of content types with as much diversity as possible.

Assume the website has a universal search bar across the site which only allows for keyword searches (no additional options). The results page is the first page they see after searching from this context. What should they see?

How should search results for different content types be displayed?