Q.flowering rhubarb
If a rhubarb plant is flowering, can’t that be used to grow a new plant? I have a plant that I cultivated from an older plant a few years ago. It has a “flower” on it (going to seed). I’d like to try to use this to grow a new plant a few feet away.

The recommended means of propagating rhubarb is by division - instructions on how to do so are found here:
https://www.gardeningknowhow.com/edible/vegetables/rhubarb/dividing-rhubarb-plants.htm
You can try propagating by using the seeds, but I read that the seedlings rarely resemble the parent plant since most rhubarb is cross-pollinated. So you would probably end up with rhubarb of poor quality. You can read more about this at the following extension website:
https://bit.ly/1HtcJl7