The moss rose (Portulaca grandiflora) blooms best under hot, dry conditions and makes a splendid ground cover. Moss roses bloom in many bright colors, including shades of red, orange, yellow, purple and pink. They hoard water and need little care. You need only pinch off spent blooms to encourage budding and to maintain their neat appearance.
How to Buy Seeds for Moss Roses
Most moss roses sold in single packets will contain a multicolor selection. These will make a cheerful edging or work effectively in large containers. If you wish to have solid-colored swaths of moss roses in your garden, purchase seed packs containing single colors.
Where to Plant the Moss Rose
In order to get the most growth and fullest expansion from your moss roses, plant them where they will be in direct sunlight for 6 to 8 hours per day. Check that the soil temperature is above 70 degrees F (21 C) before planting seeds, in order to burst the seed covering and start germination. The soil must be extremely dry, or the seeds will sprout and then wilt within hours: a condition called "damping off." A sloped or terraced flowerbed will keep the soil at optimum dryness.
Place the seeds about 12 inches apart in shallow dips, about 1/2 inch down in the soil. Cover the seeds minimally, and water with a few drops at each planting site.
Moss roses may also be grown from young plants. Plant about one inch down in the soil for support, and add some fertilizer to the potting soil upon planting. Water them then, and allow soil to parch between waterings.
The massed color of moss roses, and their maximum height of only eight inches, makes them well-suited to use as borders. Plant them in clumps among paving stones to define a garden path, or employ them to replace the grass on boulevard and median strips. They can also vividly frame a fountain or garden statuary. Choose locations that get the maximum amount of sunlight.
When to Water the Moss Rose
The moss roses are succulents, plants with superior drought-resistance. They store water in their leaves and stems, so overwatering will rot the roots. Water the moss roses you have planted rarely, only when the soil is extremely dry. The best times to water are just after sunrise or at dusk.
How to Grow the Moss Rose in Containers
Moss roses are ideal for container gardening, due to their small size and need for light and well-drained soils. Any type of hanging or standing container with a well-perforated base will suit the moss rose. Hang a cascade of baskets with moss roses in differing shades of the same color for a pleasing composition. Shallow urns filled with a single or alternating colors of moss rose can highlight the corners or one edge of a patio.
The robust massed growth of the moss rose will add definition to any garden layout. You will enjoy their abundant color in the scorching summer heat.