If you grow them in rich moist soil the leaves will grow larger at the expense of flowers. This is the opposite of what is usually recommended. I imagine that the standard, rampant, trailing, orange ones would be best rather than any named strains. Mine self sow every year and about the largest I get are around 4 -4 1/2 inches across.

Thanks for the tip. I would be thrilled with 4 inch leaves.

I agree with floral. A pic of mine at the link.

Climbing Nastutium

tj