rhubarb - what's the best way to sweeten for custardo and crumble

[wishywotz]

rhubarb can be a little tart sometimes, I find adding sugar helps to make sweeter, how much do you need?

I always do it to taste, ie add a bit, cook & taste and add more if needed. Have no idea of exact amounts.

rhubarb with stem ginger is v nice and v sweey and great for crumbles