Just to lay this down, they aren’t your typical ent. They’re more human-ish(by that I mean that I adapted them for DnD). They can survive in desert climates.

Here are my current features. Some ideas would be appreciated!

Ability Score improvement 

Increase one score by 2 and your constitution score by 1.

Entish language

You can speak Common and Entish.Proper Entish is a slow language, but, if you try,

you can easily get a point across in a short time. Plants can vaguely understand this language if you are within touch range.

Heat resistance

You can survive temperatures of up to 150 degrees Fahrenheit without additional protection.

Welp, this is where my train of thought ends.

You could search the volodni or pine folk from from Unapproachable, the hamedryad from 4ed and the plant "races" from Starfinder. 

Thanks

I want to ask a question, and it's "what are you hoping to get out of an Ent race (that isn't already represented in another species)?" I ask in order to suggest that the clarification of the story or ideal which the species will embody will help with articulating the kinds of mechanics that make sense. Con +1 and Any Attribute +2 says that this species' story is anything a player wants... and that's not exactly a direction yet... The idea of a character who can speak with plants at will (and I'd go so far as to say just give the spell as an at will or as a per PB type thing [alternatively, just have the effect always on...]) is intriguing and it plays into archetypes that emphasize connection with the natural world. That's close to a direction--albeit one that's fairly explored by the Druid class... Heat resistance seems out of line with Tolkien's depiction, and I don't know that it's in service of a cohesive archetype...

In what's already presented, I'd interpret this species as something like a way to take a dip into the druid class without using a class level. That could be fun, so I'd think about ways to reformulate the gnome's tinkering abilities into a poor man's goodberry (remember how Tolkien's Ents made brews that nourished Pippin and Merry?); I'd think about ways to add natural AC with inspiration from barkskin (maybe something like "you're AC can't be lower than 10 + PB); I'd think about some kind of natural camouflage or tree-shifting ability. Maybe you could add additional senses? Maybe additional speeds? Also, maybe resistance to fey influence...

Dragon Stew has a Harvestborn Barkling which has a cactus variant.

Sprouting Chaos has a Silva with forest and jungle subspecies.