So what is a simple method for fertilizing houseplant? Fertilize at the rate recommended on the label of your fertilizer from March through October. Don’t fertilize at all during November through February unless the plants are receiving supplemental lighting. If they are, then fertilize the same amount throughout the year.
If your fertilizer recommends fertilizing once a month, try splitting the concentration recommended in half and fertilize twice a month. The total amount is the same but the frequency is doubled which may result in a more efficient use of the fertilizer. (Ward Upham)