or..dont bother with fungicide at all..
I have been using the "fridge method" for almost 2o years..
never once used fungicide, never once lost a plant to fungus..
every spring I have light wispy strands of some sort of fungus on the surface:
and that photo shows the *worst* of it! most pots have much less, or sometimes none at all..
and its just strands growing between the "stumps"..or on dead material.
it doesn't harm the plants at all, and it disappears after a few days in the open air and sun in the Spring..
and..fungicide is pretty toxic stuff..I wouldn't want it in the fridge with food!
If your dormancy was going to be warmer, say in the 40's or 50's Fahrenheit, then you might want to use fungicide,
because mold would grow better at those temps..but in that case, your plants are probably outside, they aren't wrapped up,
so they wouldn't need fungicide anyway!
But for a fridge at 35 degrees F, that is cold enough that barely any fungus grows..the cold keeps major growth in check.
and what little does grow doesn't harm the plants at all..
so my opinion..If you are using the fridge, don't use fungicide at all, because you don't need it..
been doing it that way almost 20 years now..
Scot