Or different kinds of plants
Please post picture of each one.

Where do you live?

This post was edited by jean001a on Fri, Jun 13, 14 at 20:33

Maybe the large one was planted in amended soil or just better soil. Maybe it gets more water somehow or more light. They could be the same variety, a different variety, or one (or both) could be from seed. There are a lot of factors that affect size. And it's impossible to say which specific one it is unless they are growing next to each other under the same conditions.

I do know that rhubarb started from seed has a ton of natural variation. I've got 37 seedlings that I started earlier this year. Some have red stalks, some have green, there's one that is almost a yellow, and there are major size differences among them. They've all received the same care so nothing else but genetics can account for these differences.

Rodney