Tips & Care: How to fertilize your orchids

In the rainforest, the  orchids get their nutrients from water that runs down the  tree and in between the bark by way of the roots that are attached to the bark. Most of it is fine organic material comes from the parts of the tree of from animal feces washed off of the tree by rain. But in reality, they  make their own food by combining water with carbon dioxide  and the energy they derive from sunlight through a process known as photosynthesis. 


Unfortunately, This would be very difficult to mimic at home. You can use fertilizer to overcome these problems. But orchids require only moderate amounts of fertilizer to naturally grow well.  On the other hand, if you try to speed their growth by fertilizing orchids more than they should, there’s a high chance that the plant’s health will suffer due to the extra chemicals.  The leaf tips will become brown from the excess sodium, and the roots will burn and shrivel.


A good schedule is the commonly known as "a weak weekly approach" to fertilizing orchids. In this case you would follow the instructions from the manufacturer (because the concentration of nutrients vary from one to the other) but I recommend for you to make the solution at quarter strength. The fourth time you are "supposed" to fertilize,  skip it in order to keep the minerals from the fertilizer from building up on the potting medium. You can flush your plant with clean water at least once a month.  Even if you fertilize your orchids lightly, skipping this step will cause salt deposits to build up in the soil and burn the roots.  It will be as if you had over-fertilized your orchids.During the winter or cool months when the plant is resting fertilize half of what you have been doing during the growing season. Water often enough so the plant does not completely dry out. Mist the leaves every other morning if you are using the heating, do not forget that the micro climate can get too dry for the orchids, and they don't like it. 

The new orchid enthusiast may be initially overwhelmed by the many kinds of available fertilizers. Some stimulate growth, others improve blooming, and there are those with extra magnesium, iron, calcium, etc. Despite all these options, fertilizing orchids is a fairly straightforward process, and most orchids (even hybrids) thrive beautifully with a simple fertilizing program.

Any commercial fertilizer should ideally contain,  roughly seventeen distinct elements, divided into Macro and Micro nutrients, where the macro nutrients are: Nitrogen (N), Phosphorus (P) and Potassium (K). Although they are needed in smaller proportions, orchid plants also need micro elements such as Calcium (Ca), Iron (Fe), Copper (Cu), and Zinc (Z). And in even small quantities, orchids need a wide variety of trace elements.

A good orchid fertilizer should have all of the elements I listed above and a commercially packaged fertilizer will denote the percentage of its macro elements in the following order: Nitrogen (N), Phosphorus (P) and Potassium (K). For example, if the label reads 15-23-40 if means that the said product contains 15% Nitrogen (N) plus 23% Potassium or Phosphates (K) plus 40% Potassium or Potash (K).

Do you know what each macro nutrients is for?...Gladly I will tell you really quick about them. 

First, Nitrogen is the macro element that paints the orchid leaves in their deep green color as it promotes their growth and is also needed for the growth of the stem that will carry the orchid’s magnificent bloom.

Phosphorous is the macro element that promotes the development and growth of the orchid plant’s root system and its breathtakingly beautiful and eye catching flowers.

Potassium is the macro element that is instrumental in building the orchid’s tissues and helps it produce the chlorophyll without which it cannot survive.

If you would like to get more technical and thorough about fertilizing orchids, you may invest in a pH meter.  This instrument is based upon the fact that orchids can only absorb nutrients if the fertilizer mix is within a proper pH range.  

This range is generally 6 or 7 for acidic orchids.  Fertilizer is normally acidic, but the pH level can drop to 6 and below when mixed with pure water.  If your orchid’s growing medium is acidic due to peat, spaghnum moss, or decaying organic matter, this low pH level may interfere with nutrient uptake.   This won’t be a problem if you use water with high mineral content, making the pH level alkaline. When mixed with fertilizer, the naturally occurring minerals in water will balance the pH level out to the optimal level of 6 or 7. However, you can only be sure by testing it, and this is where you’ll find the pH meter handy.

Fertilize your orchids 2-3 times a month during the warmer months (easier for me is to do it every other Sunday morning) and 1-2 times per month during the winter when growth is slower. Unless you are using rain, or reverse osmosis water that is very pure, you should  flush your plants thoroughly with water at least once a month to get rid of excess salts.

Orchids potted in a bark mix, use an orchid fertilizer with a higher nitrogen content (such as 30-10-10) or a 'urea-free' formulation. For those plants in a peat-based mix, or sphagnum moss, a  balanced 20-20-20 formulation or 20-10-20 is fine(see box for more information).

In both cases, switch to a 'blossom inducing' fertilizer (such as 10-20-10) once new leaves have matured, generally in the later summer and continue to use this during flowering.  Alternatively, switch between fertilizers each time you feed.

I hope you found this post interesting enough to start practicing your fertilizing technique.
So, remember how to read the labels, compare them one to the other depending on your orchids needs, specially on the season you are, and then...do not overexpose the orchids to it...just do it regularly with a low strength each time and you will get beautiful blooming season this coming spring/summer.