In article ,
Ole Kvaal wrote:

This question may be more linguistic than botanic, but here I go:
yesterday I bought a bottle of Pokon 4-4-4 bonsai food. On the back of
the bottle it reads: "Fill top of cap and dissolve in one quart of
lukewarm water". What is "one quart"? Some sort of measure I'm unaware
of, or some misspelling or missing word.

That depends on whether it's a US quart or a British Imperial quart.
A US quart is 0.946 liters, an Imperial quart is 1.136 liters.

I'd play it safe and use the larger amount.