I don't feel like I could say "yes" or "no".
Suppose you diluted it to 1/4 of the suggested rate and only watered with it lightly.
Then I'm pretty sure every other month would be far enough apart.
But if you totally flooded the pot with the strongest concentration recommended - what if your soil held a lot of water? Then even every two months might be too often.
My belief is that so many things vary from one person to another that very few simple or concrete gardening rules can apply to everyone. You have to watch and learn and make your own rules.
If you dose them every other month with "some" 1/2 strength, not a huge amount and not just a sip, probably no problem. Just watch them to see if they get yellow.
(I'd suggest using the same cup to water with each time. Then you get a better feel for how much water they need, and how much it takes to flush the pot, or how much just to wet it down to near the bottom.)
You might need to fertilize more often, or use more fertilizer. Just increase gradually until they don't yellow towards the end of the 2-month period.. Once they look happy for several months, stop increasing the dose or back off a little and see if the new level is enough.
Does anyone have suggestions for what the tradeoff is between frequent small fertilization and bigger doses less often? I lean towards more dilute rather than "strong", just out of caution. The only indoor plants I grow are seedling trays and potted-up seedlings, They don't need much food!
