Dahlia Tartan. The Tartan is a so-called Dinner Plate Dahlia because of its large flowers that can get a circumference of 30 cm. This variety with its burgundy-red and white double flowers is a real gem in any summer garden. This richly flowering dahlia loves a spot in the sun and flowers from July to October. A real eye-catcher in your garden. Grows to a height of about 90 cm.