Portulaca, also known as moss rose or purslane, is an annual flower that is native to the dry areas of South America. The plant is multibranched with semisucculent red-colored stems and green leaves that produce roselike flowers approximately 1 inch in size. The bright-colored flowers bloom in shades of red, pink, white, yellow and orange. The plant is hardy in USDA growing zone 5 to 11 and prefers a well-drained, poor quality soil.
Sow seeds indoors approximately 2 months prior to the date preferred for planting outdoors. Plant seeds in a seed-starting soil and cover with a plastic bag. Refrigerate for 15 days to start the germination process. Uncover the seed tray and move it to a location that is 70 to 85 degrees F after the 15-day refrigeration. Continue to grow the seedlings until they are ready to plant outdoors.
Harden portulaca seedlings prior to planting by placing them outdoors during the day and bringing them inside in the evening for 1 to 2 weeks.
Plant the seedlings in a full sun location after the last spring frost. Portulaca grows well in poor quality soil that drains well and has a slightly acidic pH of 5.5 to 7. Space portulaca plants 10 to 12 inches apart when planting in the ground.
Sow portulaca seeds directly on top of the soil after the last spring frost, if preferred. Water lightly to prevent scattering until the plants have germinated.
Water portulaca plants at the stem base on a regular basis to promote flowering. Portulaca plants are drought resistant but will bloom best if the ground is not allowed to dry out.
Fertilize portulaca plants once or twice during the growing season with a standard flower fertilizer to promote flower production.
Remove faded flowers from the plant throughout the growing season to promote new growth.