Hello!
I am so glad to have found this forum thanks to the book from Audrey Nickel - The Irish Gaelic Tattoo Handbook.
I would like to express my love to nature in a vegetal tattoo. Plus, I have irish roots and I would like to reconnect to them through this tattoo.
I am thinking of the words "Mother Earth".
Thanks to the book, I would translate it as "Mháthair Talamh".
Could you please help me with this translation? Is there an irish expression better expressing love to nature?
Thanks a lot for your help!

Hi! Well, I’m still a learner myself, and by all means don’t take my thoughts here as fact, but, with that disclaimer:

I believe it would be Máthair Talamh…

There wouldn’t be any lenition (an extra h) in Máthair, unless it’s preceded by the article “an” (the)

i.e. an Mháthair Talamh (the Mother Earth) …which may also be just as appropriate a version, but I’m not sure. Maybe someone else could hop in here with an answer to that?

I do know that with familial titles such as Aunt, Uncle, etc., there is no “the” in the title. But with religious/other official titles there is a “the” (e.g. an tAthair Ó Laoghaire “Father O’Leary”)

On the website https://www.teanglann.ie/en/eid/Mother_Earth the term “an Talamh Torthach” is given (which literally means “the fruitful earth.”

“Gráthóir Dúlra” might also be nice, as it means “nature lover.”

Anyway, I hope this was of some help, and good luck!

Thank you so much for your answer!
Actually I love your proposition of "nature lover" which might be even more accurate regarding the feeling I am trying to express. In your proposition “Gráthóir Dúlra”, what is the word for nature and the word for lover please?
This one is really great also: “an Talamh Torthach” - “the fruitful earth”!
Thanks again!!!
I'll wait for other answers as it is the rule here, but I am already really happy with your answer :-)

Talamh is rather soil or the surface of the earth than the planet itself which is domhan ("world") or cruinne ("roundness", though often rather used for the universe)
And talamh torthach is just fertile land, topsoil.

https://www.tearma.ie/q/mother%20earth/
has International Mother Earth Day as Lá Idirnáisiúnta ár Máthair-Chruinne ("Int’l Day of our Mother Earth")
So, Máthair-Chruinne for Mother Earth

And there is the Earth Mother, Ollmháthair na Cruinne ("great mother of the Earth")
Máthair na Cruinne would do as well, I’d think.

In “Gráthóir Dúlra,” gráthóir is lover. And dúlra is nature. So literally: lover of nature.

In Connacht and Munster regions, (Southwest and Central West areas) it would be pronounced (GRAW•horr)(DOOL•ruh)

In the Ulster region (Northwest), it would be pronounced more like (GRAA•hawr)(DOOL•ruh)…with a short aaa sound in GRAA.

I was gonna send you the dictionary link for the Focloír.ie nature lover entry, but, for some reason that term only shows up in the app and not the web version. It might be fun to get the Focloír app. It’s free and has most words (not this particular term unfortunately though) audibly pronounced in all three dialects.

Thanks a lot for your answers!
It is super clear :-)