Cynara cardunculus, Cardoon?

Thank you, Omar for the very helpful lead! It appears that the first one is Corpus Christi fleabane (erigeron procumbens). I will see how it behaves before determining to keep it in my garden bed, lol. The second one is very probably, as you suggest, a helianthus. It is growing underneath another plant and appears to be in need of more sun. I will keep my eyes on this one as well. It's possible that they will both be keepers in my wildflower garden! Thanks again, Molly

That looks correct based on the web search for black mustard. Thank you for the quick response.

Whenever we talk about plants and gardening we need to know where you are situated geographically. Without knowing your climate and temperatures we can't say whether your seedlings are doing well or not. In my climate three weeks for germination would not be unusual. For the same reason, and also because we don't know what species you have, we can't say when they'll bloom. They look ok from what I can see but can I ask if you are watering with a fine rose or just a spout? The reason I ask is that it looks as if you might have washed the seeds around which would disturb them. eta, sorry, I didn't notice California in the heading. But even so that's a big place with different climates.