When a rhubarb flowers, this is called bolting or going to seed. When rhubarb goes to seed, this is perfectly normal. The rhubarb plant is doing what plants are supposed to do and that is trying to reproduce. But there are some factors that can influence how often you get a flowering rhubarb.1  Variety – Some varieties of rhubarb flower more than others. 2  Maturity – Plants need to reach a certain maturity in order to reproduce through seed. 3  Heat – Rhubarb plants grow best in cooler temperatures. 4  Stress – Stress can also force a rhubarb to flower.ut there are some factors that can influence how often you get a flowering rhubarb. 1  Variety – Some varieties of rhubarb flower more than others. 2  Maturity – Plants need to reach a certain maturity in order to reproduce through seed. 3  Heat – Rhubarb plants grow best in cooler temperatures. 4  Stress – Stress can also force a rhubarb to flower.