How to apply formula to whole column, when cells are temporarily blank, without dragging down?

In column H, I will have the prices of books I'm ordering (I'm a librarian). In column K, I want to have those prices with $2.54 added to each price to reflect the cost of processing. So I have the simple formula =H+2.54, but I want to apply it to every cell in column K. I haven't started ordering books yet, so the cells are all blank. If I just do the drag-down method, every cell will show $2.54, and that will skew other data in the spreadsheet regarding how much has been spent so far. So I want to have the formula apply to all the cells in column K *while leaving the cells temporarily blank*.

The tips I've been reading about this are mostly about creating a table, which seems too complicated for an Excel dummy like me. I'm looking for a simple way to do this, if there is one. It seems like the IF or ISBLANK functions might be another way, but if so, I'm hoping someone can give me the exact formula I need to make this happen. I don't have the intuitive Excel skills to figure this out based on the tips I've seen online.

Thank you!