Purslane is a succulent, creeping weed that can grow almost anywhere. It grows from a single taproot, spreading out its stems in a spoke-like fashion. Purslane spreads through the dissemination of hundreds of thousands of seeds per plant which can live in the soil for 40 years. Once established, purslane is difficult, but not impossible, to kill.
Pull individual purslane plants out of the ground if you do not have an overwhelming infestation. This is easier when the soil is moist. Place the plants in a trash bag and throw them away. Leaving the plants on the ground may lead to re-rooting.
Place a 3-inch layer of mulch over the bare areas of your garden or turf. The seeds will not be able to germinate without the sun. The best mulch to use is synthetic mulch made especially to block sunlight.
Apply a pre-emergent herbicide for crabgrass, which will also kill purslane, in early May to the areas typically affected with purslane. This type of herbicide will stay in the soil and kill the seeds and seedlings in early stages. Look for herbicides with dacthal, balan, betasan, or tupersan as the main ingredient. Follow the application directions on the package.
Try solarization in July and August if your purslane plants return. Water the soil around the purslane deeply, moistening it. Stretch clear plastic over the purslane plants, placing heavy objects such as bricks on the edges to keep the plastic in place. Keep the plastic over the plants for four to six weeks during this hot period. The intense light and heat will kill both the plants and the seeds at the surface.