Q.How to Grow Rhubarb
I have a rhubarb plant that hasn’t done well in years past. It starts out good then insects start to eat the leaves and it dies back. Last fall I used 12-12-12 fertilizer and it is growing very well this year. It shot up three large stocks with seed flowers that I let go to see what would happen. The plant looks very healthy and large. Have I cured my problems by feeding it? When is the best time to cut the stems to make jam from it? The stems are green, not red, never did get red.

Certified GKH Gardening Expert
Yes, likely the fertilizer did give it what it needed. You can fertilize in the spring.
Rhubarb can be fertilized when the stems get to be about a foot tall and you can keep harvesting (though don't take all the leaves) until late June.
There are some varieties of green rhubarb. The stems don't turn red when ripe or anything, so if yours always stay green, you may have a green variety.