The moss rose (Portulaca grandiflora) is a low growing flowering annual plant with small paper-thin flowers. The flowers on older varieties of portulaca often close late in the afternoon or on cloudy days. This is why some people call the flower “four o’clocks”. Now, there are newer types of portulaca that stay open longer and they can also grow well in hot, dry weather. The rose-like flowers are available in many different colors such as pink, white, red, yellow and orange. Portulacas are commonly available in six packs from home and garden centers but they can also be grown from seeds.
The small flowers of portulaca are often about an inch in diameter. Some are cup shapes while others are double or semi-double. The leaves are long and slim like needles but they are succulent. Moss roses generally grow about four to eight inches tall. There are many different varieties of portulaca. Peppermint Hybrid bears white flowers that have pink streaks. Sundial Hybrid is a common colorful variety with multicolored flowers. Double Mix is comprised of various flower colors and has rose-like blooms.
Uses for Portulaca
The moss rose was first found growing in South America, at the base of the Andes Mountains. In the 1820s gardeners began cultivating it as an ornamental bedding plant as they do now. Some people use portulaca as a culinary herb. The seeds are edible and can be used in recipes for things such as salads.
Portulaca is heat and drought tolerant and will do well as an edging paving such as a driveway or a sidewalk. It also spreads and makes good groundcover. Because of this, it is good for erosion control on dry sloping hills. Moss rose brings a nice spot of color to rock gardens. Portulaca plants are a good choice for pots or window boxes as they do not need as much water as some plants. A scattering of moss roses growing in a strawberry jar makes a nice garden display.
How to Grow and Care for Portulaca Plants
It is fairly easy to start portulaca indoors from seed. Plan to begin this about six to eight weeks before the last frost date in the area where they will grow. They are best started in peat or newspaper pots so their roots do not have to be disturbed when transplanting. Fill a pot with soil and scatter the seeds over the top of the soil. Do not cover them because they need light to germinate. Water the seeds gently by spraying them with an atomizer. Place them in a warm sunny spot. The seedlings should emerge in about a week to ten days.
It is also possible to propagate moss roses from cuttings. Just cut a stem off the portulaca plant. It should be about three inches long. Remove the leaves from the bottom inch of the stem and stick it in a pot full of soil. Keep the soil moist and the pot in the shade. The portulaca cuttings should root quickly.
Portulaca transplants can be grown outdoors after last frost. They are commonly available in six packs at garden centers if the seeds were not started at home. Plan to grow the portulaca in full sun and average well drained soil. But, they can also do well in poor soil. The transplants should be spaced about ten inches to a foot apart. Portulaca does not like excessive water so only water when it is very dry. These plants are susceptible to fungus problems if they get too wet.
To care for growing portulacas prune them occasionally, particularly if they look scraggly. Make sure the plant gets enough air circulation and light to all parts of the plant. There is no need to deadhead the moss rose but pruning will help keep the plant healthy. Portulaca will die back with the first frost, but it can reseed itself and reemerge in the same spot the following spring.
Resources
How to Grow and Care for Moss Rose (Portulaca)
Portulaca, on Love to Know
Catherine Mezensky - Catherine A. Mezensky is a writer and artist living in Baltimore Maryland. Her topics include gardening, film, culture and local history. ...
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