Answer: Portulaca generally self-sows without any encouragement at all! Is it possible that the flowerbed is so thick with plants that the seeds can't make contact with the soil? You might try pulling the plants up at the end of the season, when the seed pods are ripe and shaking the plants over the bed. Seeds should germinate where they fall. The seedlings you're digging from the rest of the yard are from seeds blown by wind, transported by water, or dropped by birds. Try pulling the plants just as the seed pods are ripe and collecting them in a bucket. Then work the bed over, adding organic matter and raking it smooth. When it's all finished, shake the plants upside-down over the prepared bed. Hope this helps you get Portulaca plants right where you want them!
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