Direct seed claytonia in a spot with shade or partial shade up to four weeks before your last frost date. Soaking the seeds in water overnight directly before planting will help with germination. Plant seeds 1/4" deep and about 1/2" apart, then thin to 4 to 6 inches apart once the seedlings emerge. Make sure to keep the soil consistently moist until germination. Greens will be ready to harvest in about 40 days. Pick individual stalks or leaves, or cut whole plants above the soil line the way you would harvest baby lettuce. Plants will usually support multiple cuttings. In warm climates, claytonia will become bitter in summer and may die back. Some growers plant a second round of claytonia in the fall for production over the winter.
Claytonia, or Miner's Lettuce (Claytonia perfoliata) will flower as the days lengthen and temperatures rise in summer. To collect seeds, cut whole seed stalks when the pods start to turn brown and place them on newsprint or paper towels indoors. It's a good idea to put them inside a large bowl or container too, since the seed pods burst as they dry out and can fling seeds up to a foot or two! Once the seeds have separated from the pods, separate out any chaff using screens or sieves, or by winnowing. Store seeds in a cool, dark, and dry location and use them the very next growing season, since claytonia seeds don't keep for an extended time period.