'Garden Formal' combines elements of formal attire with a relaxed, outdoor vibe. Think of it as a blend of elegance and comfort.

Martha Stewart says....."A garden party dress code suggests some level of formality without needing to break out a tux or gown. I'd suggest a knee-length or midi dress, a jumpsuit, or a suit. Think cheerful when it comes to color, and don't be afraid to incorporate some florals into your look, like a printed dress or patterned tie or pocket square."

For ladies -this blog summarizes it perfectly

For the men - reference this blog