Chat Noir are a sumptuous cactus dahlia with garnet-red flowers, which have a near-black centre. They have long flower stems and a superb vase life. Itâ€™s a double flower having long and narrow, pointed petals that recurve for more half their length. Height 100 cm. Flowering July-November. Dahlias are tender tubers. Plant them before the frosts are over, they may get frosted and die, so it is advises to pot them during late March or early April, in a three litre pot with multi-purpose potting compost. Keep them in a light, frost free place and ensure the compost is kept moist. They can be taken outdoors when the danger of frost has gone . Compost : Dahlias grow and flower best sunny spots and they thrive in a fertile soil, with good moisture and good drainage.