Yes, there will be a question regarding that on your RSVP form.
Kids are welcome, we just ask that if they cause a distraction during the ceremony that you would kindly step away.
Yes, parking is free at the Denver Botanic Gardens, but the structure can get full. Parking in the residential area is permitted, just be aware of certain signs or rules.
The ceremony will begin at 5:00pm, but guests have access to the gardens all day. Should you want to arrive early, you're free to do so. Though there will be some time to explore the gardens during cocktail hour.