Traveler looking for garden spots

I'm sure you all see many of these posts, please forgive my questions if they are common.

I'm coming to Cork in the last couple weeks of August and I'd really like to see some gardens/parks. I think this will likely be my main activity. I'm planning on renting a car, and don't mind a bit of a drive.

Natural parks, botanical gardens, native gardens, sculpture gardens; any suggestions for the best ones within an hour of the city would be greatly appreciated.

Bonus if you can point me to any good vegetarian restaurants. I can find a list if I search, but I find with food, it is better to ask locals.

Cheers!