Why "ma robe a fleuris"?

Question

One option given here for "my flowery dress" is "ma robe a fleuris."  Why not "ma robe fleuries"?

Accepted Answer

Hi Carl, 
What is given for ma flowery dress is only -
ma robe à fleurs 
if it was my striped dress it would be -
ma robe à rayures
if it was my polka dot dress 
ma robe à pois
or even

une chemise à motifs = a  patterned shirt 
une chemise à manches courtes/longues = a short/long-sleeved shirt

In this case, we use the preposition à to describe the garment.
A few examples when you would use the adjective 'fleuri' which means 'in flower' or 'covered/garnished with flowers' -

un panier fleuri = a hanging basket
des parterres fleuris = borders full of flowers
une pièce fleurie = a room full of flowers

Hope this helps!

Answer

According to definitions of meaning, either < à fleurs > or < fleuri(e)(s) > are fine. Académie française and Robert both note < un tissu fleuri > for example. Wordreference < une veste fleurie >. In usage < une robe à fleurs > is likely more common.