I read one of your Answer:s regarding my Ponytail Palm but now am wondering if it requires or appreciates any special type of plant food. I found out recently that some of my plants are acid loving and have been thriving on Miracid. I want to give my palm the correct type of food.
The value of plant food for indoor potted plants is vastly over stated. Indoors, plants are growing under less than ideal conditions and use nutrients in very minute quantities. It takes several years for nutrients to be depleted from plants grown in good potting mixes. Plant food is not medicine and cannot be used to improve plant health unless the plant has been diagnosed with a specific nutrient deficiency.
I cannot comment on those plants that have apparently thrived with Miracid. It may be that they are responding to improvements in your care, not the Miracid. If you let me know which species you have, I can tell you whether an acidic soil is warranted. Most common indoor plants, including Ponytail Palms, should not be given Miracid.
If you are going to use plant food, for most indoor plants a 3-1-2 nitrogen-potassium- phosphorus ratio is best. In addition, the plant food should include minor and trace minerals listed on the label. Foliage Pro by Dyna Gro makes an excellent general fertilizer for indoor plants.
If you opt to add plant food, remember that more plants are damaged by excess fertilizer than from inadequate nutrients. The label directions are for healthy plants grown in ideal greenhouse conditions. Thus, it is best to dilute any plant food to half-strength and use it monthly only when the plant is healthy and growing vigorously.
Optimum light and proper watering are far more important to healthy growth than plant food.