If you live in California, and want to grow this wonderful edible native plant, miner's lettuce (Claytonia perfoliata), now is the time to save some seed. I wrote about it in Golden Gate Gardening, as an edible weed, but it's so good it is worth growing on purpose.
If miner's lettuce grows somewhere nearby, you can collect it now, save the seed. Then, in Fall, you can scatter it. It should be well up in December, and then will make its lovely, succulent leaves, so delicious in a salad, until the following April.
To find seed for next year, look now, in late April or in May, for plants with circular leaves that are still green and have long flowering stems. Thse will have a number of seedpods forming on the stems, with maybe a flower at the top. Gather some of these leaves, or, if you like, a whole plant bearing a few of them.
Spread what you have collected on newspaper indoors. Use a fully opened piece of newsprint, or maybe two or three together. As the pods dry, the seeds will pop out, and will actually jump up to a couple of feet from the pod. Thus you will find them all around the paper, or, if it is too small, on the floor nearby. The seeds are small, rounded, and shiny black. They have a white tip on one side where they were attached to the pods.
The process will take a week or two. Here you can see the seeds and bits of pods around a plant that is drying. After the seeds pop out, you will have to separate them from the chaff. You can do this with various kitchen items, such as collanders or sieves. I used a sieve, which left me with some tiny fine chaff mixed with seeds, then blew lightly to get the chaff to fly away. It doesn't have to be perfect, of course, but seeds are easier to sow if they are free of debris, and also any bits of plant mixed with them can bring moisture that can lead to decay.
Here's a closer view of some of the seeds before I cleaned out the chaff. After you've removed most of the chaff, keep the seeds in an open dish or jar for a couple more weeks, to make absolutely sure they are dry. Then you can store them in a paper packet or you can close the jar. Be sure to label your seeds as Miner's Lettuce and write the date of the year you saved the seed.
Make a note in your calendar so you'll remember plant the seed in October. Scatter it in an out-of-the way corner of your garden, in moist soil you have amended and dug. Scratch the soil surface a bit after you sow, pat the surface lightly, and then water. Water to keep the surface moist if rains don't do it for you. The seed leaves are long and narrow. The first few leaves will be triangular. Then the mature leaves form, the round ones. You can eat them, flowers and all, after the flowers start to form in their centers, but when the flower stems elongate they are ready for another year of seed saving. Or just let some fall in place, in hopes the plants will self-sow!
Here's a salad containing miner's lettuce, corn salad, edible flowers, and some cut up chard stems.