Botanica?

[Sky Shadow]

Those are rocks though... I don't know if there has ever been a transforming plant toy before?

Saberback/Striker/Snarl and Sling have plant modes.

[griffin]

Saberback/Striker/Snarl and Sling have plant modes.

Officially, or just names given to the weapons painted like plants?

Not debating you - just asking, as I'm aware of those JP Beasts, but not recalling any names given to their weapon gimmicks.

[GoktimusPrime]

They're "trap" modes -- parts that open to look like plants and ensnare flower-sniffing Maximals. It's not quite the Botanica toy I'd like... but I guess it's better than nothing.

[Sky Shadow]

Officially, or just names given to the weapons painted like plants?

They are officially plants/flowers in the same way as any Transformers mode is - i.e. they're robots in disguise. Yes it seems pretty stupid that the Maximals would fall for the 'flower trap' thing even once, let alone more than once, but there's an amusing scene in Beast Wars Neo, where Break and Cohrada 'flamethrower' a whole 'field' of flowers because they're not sure which one is Saberback. (It turns out that he was actually behind them.)