A Guide to the Care and Varieties of the Moss Rose (Portulaca grandiflora)

The moss rose (Portulaca grandiflora), commonly known as "the flower that cannot die," is also called the sun rose, purslane, or moss rose. It is an annual succulent herb in the purslane family (Portulacaceae). Its stems and leaves are thick and juicy, with slender cylindrical leaves, and its flowers grow singly or in clusters at the tips of the branches, in a rich range of colors including red, yellow, pink, white, orange, and bicolors. Because a single piece of stem stuck into the soil will take root, and it survives sun, drought, and just about anything, people gave it the vivid name "the flower that cannot die."

Its greatest trait is that it is tough and easy to grow. It loves full sunlight and a warm, dry environment, tolerates drought and poor soil, and its only fear is waterlogging. The more light it gets, the more abundantly it blooms. Its flowers usually open around midday on sunny days and close in the evening or on overcast days, which is how it earned the name "sun rose." Its blooming period is very long, lasting from early summer all the way to late autumn, making it one of the few flowering mainstays of summer.

Based on petal form, the moss rose is divided into single-flowered and double-flowered types. Double-flowered varieties have layered petals resembling small peonies and are more ornamental; there are also striped, gradient, and other bicolor types. It has a low, trailing growth habit, making it suitable for balcony pots, and it can also be planted at the edges of flower beds or hung in hanging baskets. When mixed colors are planted together, they form a lively, colorful display.

For care, use loose, breathable sandy soil. Follow the principle of watering only when the soil is dry, and let it dry out rather than overwater; during the rainy season, ensure good drainage to prevent root rot. Pinching and topping during the growing season promotes branching and makes the plant fuller. The pinched-off stems can be left to dry at the cut, then simply stuck into the soil to root. The best spot to place it is a south-facing balcony, terrace, or anywhere with the most abundant light.

There are two main common problems. First, overwatering or prolonged rain causes the stems and leaves to rot; controlling water and improving drainage prevents this. Second, insufficient light causes leggy growth and sparse flowering; moving it to a sunny spot will restore it. In winter, the above-ground parts wither at low temperatures. You can collect seeds in advance for spring sowing the following year, or keep a few sturdy stems to root indoors as cuttings to continue the plant.