Cider's been brewing. Too late to add sugar?

[Aróchito]

My cider's been in primary for almost 3 weeks. About to put it in secondary, but I'd like to make it a little stronger. I originially put in some sugar along with the yeast nutrient and yeast. Is it too late to boost the abv with some extra sugar? Thanks in advance.

 

[madscientist451]

I don't see why you can't, although frozen apple juice concentrate might be a better choice than just sugar. Refined sugar gives the cider a "hot" alcohol note, some people don't mind that, but I try to avoid that.
Just leave it in the primary fermenter if you are adding more fermentables.