This paper considers how the structure of Instagram and social norms on the app constitute a landscape that restricts and amplifies the flows of certain informational forms — what I term the knowledge landscape. Instagram’s knowledge landscape selects for certain ideas to proliferate across the app, leading to particular significatory and affective encounters with ideas and unique sedimentations of knowledge. To understand how the knowledge landscape influences encounters with political ideas, I analyze follower network and digital engagement data across 127 accounts and several hundred posts from “Politigram”, a loose space of activist, advocacy, meme, and ‘shitpost’ accounts engaging in left-leaning politics. Using interviews with six users and five content creators on Politigram, I explore how the space is understood by those who use it, what motivates users to engage with various content, and what engagement habits emerge. These factors reveal the topologies of the knowledge landscape that influence the flows of information through the space. Finally, I consider the processes by which the knowledge landscape reconfigures information through memeification. This paper critiques the notion that Instagram, or any media platform, can serve as a neutral ground for advocacy and education to new audiences. The possibilities of engagement are restricted by the knowledge landscape, eliciting certain behaviors from users, constricting the range of idea encounters, and producing knowledge that is qualitatively distinct from that which is encountered elsewhere.