People who rent apartments or homes may not have the room or the ability to plant flowers around the place. Therefore, one obvious audience is homeowners. Some people who rent homes can landscape, so this site is also directed towards them. People that have some disposable income.
Landscaping can become expensive.
For people who have other obligations that take precedence, spending money on flowers is not at the top of their list. People who have some extra money in their paychecks are more likely to want to spend money on flowers. Late 20's or older, these are the people that probably own their own home. College age students and younger do not have the resources to plant the flowers. Therefore, they probably would not be interested in learning about the farm.