Jim, you can certainly deadhead your celosia if the browning flower heads bother you. If you want to save seed, once the flower head has browned you should clip it and put it in a plastic bag. You should see little black seeds around the central stalk of the plant. Give a gentle shake to dislodge those seeds. Because most celosias are hybrids, you should not expect the seeds to produce an exact clone of what you have this year, but you may get some interesting variation on them.
Thanks Doug. So when it the flower browns, I can clip it, save the flower bloom in a bag till I see black seeds, then shake them out and just plant the seeds like any other seeds? Do I need to plant the seeds right away, or can they wait till Jan/Feb so the flower is growing by May? IF I plant a whole browning flower without removing the seed, will the seed propogate and the rest of the flower just turns to fertilizer or is is bad to keep the seed with the flower bloom? (( I'm experementing to learn now. ))
If you want established plants that you can plant in the garden in May you'll need to start the seeds indoors. Six weeks before your last frost date would be a good time. You can sow directly outdoors any time after the danger of frost has passed, but you'll have better results if you wait until the soil temperature is up to about 60 degrees. You could probably find a story from someone who just tossed some coleus flower heads on a compost pile and had new plants spring up, so your experiment in planting the whole flower head may work. If so, report the results here!
very good. I've started a few containers for growing seeds indoors in my sunroom, and figure, worse case - they don't grow and it's a little time and soil.
If you have a sunroom, that's perfect.