You can leave out the fresh ginger if you don't have any. I have made this dish with and without the ginger and it doesn't effect the taste massively.
I also use leftover boiled potatoes when I have them instead of using fresh, a great way to use up those leftovers.
You can also add more garam masala for a more spicy version. This is toned down for the kids.
Found this very disappointing, weak no flavour. Pretty much a waste of ingredients - I have a bowl of faintly spiced watery spinach and potato - if you like sag aloo avoid! - 06 Jan 2015
Tried this dish and wow, how tasty was this, as good as any saag aloo I have had in a restaurant, although After cooking it I did let it stand for a time while I got on with another dish which probably enhanced the flavour. Would definitely cook this dish again. - 12 Jul 2015
I don't know what the others did to get loads of moisture in their recipe. This was great. I did read through the recipe and followed most of it. I cooked the spinach and potatoes separately then drained the spinach and pressed the water out of it in a sieve and rough chopped before mixing with the rest of the potatoes and spices and finishing it all off together... I also added a teaspoon of curry powder to the mix. Everything else though is otherwise as per the op's recipe. I will do this again. Very easy to do... - 24 Jun 2015