This Nautilus article presents some research suggesting two key points:
Given how HBO’s The Last of Us uses a fungal network in the early episodes, I thought this article might be of interest to other writers.
It’s fiction, but if one is interested in the exploration of the diversity of intellects that might exists out there, I really enjoyed Sue Burke’s Semiosis (and for more reasons than just that question). One does not need to travel to an alien planet to find vastly different forms of intelligence.
Sounds interesting.
I just grabbed it from the library. 
Also fiction, but Richard Powers’s book The Overstory explores (among other things) the connections among trees and other beings in the forest biome.
And then there’s octopus cognition. Maybe not as alien as plants, but definitely different from us (and better documented than plants): https://www.scientificamerican.com/article/the-mind-of-an-octopus/
(And yes, the representational model is almost certainly wrong with regard to human intelligence.)
Just adding some recent books that might be of interest:
And
While the idea that plants can communicate is appealing, at present the evidence is scant. A Feb 14, 2023 article in The Conversation (The Conversation: In-depth analysis, research, news and ideas from leading academics and researchers.) entitled "Do trees really stay in touch via a ‘wood-wide web’? Here’s what the evidence says" summarizes some of the concerns. That article refers to a more formal assessment printed in ‘nature ecology & evolution’ called “Positive citation bias and overinterpreted results lead to misinformation on common mycorrhizal networks in forests.” published on Feb 13, 2023.
I think we are massively ignorant about these issues.