It probably comes as no surprise to you that Grass-types have an affinity for plants! But I doubt many people are aware of just how strong that affinity is! The impact these Pokémon have extends beyond that of perhaps any other type we know of!
Grass-type Pokémon are by nature expert gardeners! They have an internal sense of exactly what particular plants need in order to flourish - whether they need more or less sunlight, or water, or nutrients, the best places to plant, and so forth! It’s thought that they’re capable of picking up signals from plants in the environment that can tell them about their health and needs! While not all of them may necessarily enjoy gardening, they’ll perform exceptionally well if they have to get involved! Any large gardening operation involves lots of Grass-types - it’s essential for the successful proliferation of the plants and their output! A Grass/Poison typing seems to be even more effective - you’d think having the added Poison-typing might be dangerous, but the combination actually provides extra feedback on chemicals that can be safely used and the levels of toxic compounds that can be applied to the plants to remove pests and diseases without causing significant harm!
I’ve heard humans who do gardening, or other hard work, say that they put their blood, sweat, and tears into their work. Well, Grass-types do that too - quite literally, in fact! Their bodies contain lots of chemicals that are extremely good for plant growth, and it’s far from uncommon for bodily fluids to be willingly shed so that the gardens can grow above and beyond what you normally see! We’re talking sizes well above typical for the species, hardiness to withstand the worst of conditions, in some cases even restoring plants from apparent death! It sounds pretty impossible at times, but I’ve watched some gardening first-hand and damn if they don’t at least make it look like that’s what happens!
They also seem to have an uncanny knack for genetic splicing! Hybridized plants created by Grass-types seem to survive and thrive better than those created by humans, even professional scientists! In fact there are a lot of plant varieties out there that were created by Pokémon, and some Pokémon even have monopolies on specific plant types! I’ve met one Sceptile who actually owns a pretty sizable corporation based on demand for varieties of plants and their outputs - definitely a rare thing to see! Included among them are a ton of berry types that aren’t grown anywhere in the wild, some of which have pretty appealing properties to trainers and Pokémon alike!
I’ve heard rumors that some Grass-types even splice some of their own genome into plants...I have my doubts about that because Pokémon DNA isn’t the same as most plant DNA...though, to be honest, I think no one’s actually ever looked at the genome of Berries before...that makes me curious...