There are several advantages to creating your own orchid food. For one, it will be cheaper. It would also be more environmentally friendly and by combining the different elements yourself, you will be able to factor in the varying needs of your orchids during different parts of their growth cycle.
Various household items that can be incorporated to the benefit of your orchids. Eggshells, for example, provide a great source for calcium. Break them up into tiny pieces or better yet, crush them into powder using a mortar and pestle. They can then be sprinkled over the bark or moss of your orchids.
Banana peels, potato peels and molasses are all great potential sources of potassium, a necessary nutrient that promotes flowering in your orchids. Since the rotting banana peels may smell strongly, you could alternatively boil some potato peels with banana pieces. Just a spoonful of molasses diluted in water and added to the bark base of your orchid pot could also achieve great results. Agar, a product derived from red algae can cause the other ingredients of the mix to bind more efficiently and render the nutrients more accessible to the roots of your orchid plant.
Another organic recipe for fertilizer combines diluted coffee made from coffee grounds, crushed eggshells and a teaspoon of molasses with several gallons of water for a nutritious mixture you can add to your orchids once a month instead of water. The coffee grounds contain potassium and phosphorus as well as minute traces of magnesium and copper, but you will need to filter it out of the mix before use.
Another source of magnesium is Epsom salt. Magnesium benefits general growth in orchids and since it strengthens the roots as well, it increases the absorption of other nutrients. The flowers will bloom in brighter colors. You should dilute one teaspoon in water.
Fish emulsion is also recommended for orchids. If you own fish or know someone who does, you could use the waste water usually discarded after a fish tank is cleaned, as it is another great source of nitrogen. It will need to be diluted, though.
Salt build-up may indicate that your orchid has had too much of a good thing, but roots that die and turn brown are one of the surest signs. If that happens, remove your orchid from its pot and thoroughly rinse its roots. With some orchids the leaves may turn yellow or droop, while others may grow brown at the tips.
Remember to give your orchid a thorough watering before adding fertilizer. Dilute the mixture as directed for orchids. Bear in mind that orchid food cannot cure an already sick plant, but it can maintain and boost the performance of a healthy one.