I had 1900 grafts transplanted. Is it enough to cover the balding area? (Photo)

It can take 6 to 12 months after surgery to see results.  If you are concerned it is best to contact your doctor.

1900 grafts will certainly add significant density to your scalp.  If you haven't yet, you should discuss with your surgeon adjunctive therapy to prevent further hair loss. 

I think You will probably have adequate coverage with the 1900 grafts.   What will be most important is that he retain the existing hair that you already have.   For this finasteride am in Minoxidil would certainly be recommended  but also becoming more important would be cellular therapy such as PRP and stem cells.  If you lose any of your existing hair You will need more grafts. 

That is a reasonable number of grafts unless your hair is very fine, then more would have been better because fine hair does not have much bulk to is.