Speaking with plants

[Jeff the Green]

I'm playing a summoner archivist with greenbound summoning, and I'd like to be able to command my greenbound summons without having to spend time or a spell slot on speak with plants. I have telepathy, but as they don't have a language, that doesn't work. Is there a way to get constant speak with plants or equivalent for less than the 24,000 GP a continuous item would cost?

[Palanan]

A constant speak with plants itself could be tricky.

However, the second level of Holt Warden allows you to "rebuke or command plant creatures," which might work just as well.

I know zilch about the archivist, so pardon me if that's not feasible. First thing that came to mind.

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