I always like starting my plants from seed. I was thinking about that they recommend using seed starting mix. From what I just read seeds do not need nutrients to start growth. Like starting them in vermiculite in those thimble size compartment trays. Then you need to transplant them into pots. The idea occurred to me to fill one of the leftover 4 1/2" containers the flowers came in with the sifted potting mix. Another thought occurred to me was to take the sifted potting mix and add coffee grounds in it. I had a 2 cup measuring cup and just about filled it with the sifted potting mix I had. I then dumped in today's coffee grounds which was three scoops and mixed it all together. Put that in the 4 1/2" container and watered it down. Took some lettuce seed I got today and broad cast the seeds and covered with about 1/8" of sifted mix. added some more water on the dry mix on top. "coffee grounds contain nitrogen, calcium and magnesium that are greatly beneficial for the growth of plants." If the seeds start that should give a big boost to the seedlings once they get their second leaf set. See how that works out.
Another thought occurred to me. I could fill the pot with the mix I mentioned, then take my thumb and make a thimble size depression. Fill the depression with vermiculite and place my seed in that. The seed will start in the vermiculite and advance in growth to the potting mix with the nutrient rich coffee grounds. I did not have any vermiculite tonight so I just started the seed in the potting mix. Seems like starting one seed in a 4 1/2 inch container as mentioned will save time from transplanting from thimble size container to a larger container with the nutrients in it.
If the lettuce seeds start it is obvious I will need to transplant the wee small seedlings after they come up with that many seed in one container.
That will be another topic for the container garden saga if they come up or not.