Not only are dianthuses beautiful, but also very easy to grow. Dianthus flowers are very low maintenance. They only require cool weather, rich, slightly alkaline soil, and full sun exposure. You only need to water them once or twice a week and add fertilizer once a month. Choose the part of your garden where your flowers will get at least 4 to 5 hours of sun exposure.
Water your dianthus plant about once a week with about 1 inch of water. Discard the dead or faded flowers to encourage blooming. Never add mulch to your dianthus flowerbed. Be careful not to overwater your dianthus, as it can turn the foliage yellow. Feed the flowers about every 6 to 8 weeks with liquid fertilizer to promote continued blooming.