The two popular garden flowers that can be found in a crossword puzzle are DAHLIA and Zinnia. Dahlias are a genus of bushy, tuberous, herbaceous perennial plants native to Mexico and Central America. They come in a variety of colors and sizes and are often used as cut flowers. Zinnias are also a genus of annual and perennial plants native to scrub and dry grassland in an array of bright colors. They are popular for their long-lasting blooms and are often used in flower beds and borders.