Gardening Vivian | 30 May 2011 02:52 am
Orchid Feeding Tips and Guide
Some people will have you believe that orchids are hard to care for, and in some cases, that’s true. The old saying ‘feed weakly, weekly’ comes to mind when dealing with these unique flowers, but what do you feed? Nitrogen (N), phosphorus (P) and potassium (K) are vital ingredients for orchids, just like any other plant. The air and growing medium will provide some of this, but most orchids are pot grown, and will need supplemented. This is even more important for orchids since, instead of soil, they are planted in bark, rocks or sand.
Pellets, liquid and mulch are just a few forms that these supplements come in. Whichever type you choose, your objective is to maintain the proper balance of nitrogen, phosphorus and potassium.
Fertilizers and soil treatments will usually be labeled 30-10-10 or 15-5-5 and sometimes 20-20-20. These numbers indicate the percentages of the three elements that we discussed earlier. Do not be alarmed that the numbers don’t add up to 100%. The remaining percentage consists of whatever else the compound is made up of.
Some will allow orchids to grow on the bark of their trees, which is similar to how some (epiphytes) are found in the wild. These types will respond well to the stronger mixture (30-10-10). A medium mixture (20-20-20) is sufficient for those that are grown in pots. These levels may need to be adjusted at different times of year.
Try using a 10-30-20 mixture at the end of Summer to strengthen those last blooms of the season. It’s also a good idea in the spring, before the first blooms, to provide some extra nutrients to get them started.
Great care should be taken when fertilizing since orchids are such sensitive plants. You will risk fertilizer burn if you over do it. Fertilize your plants once a week, with the first one of every month at full strength. Then, for the next three weeks, dilute the mixture to one quarter of that. It’s also a good idea to rinse out any unwanted salt residue with water once a month.
The elements in the fertilizer will react with the elements already present in the soil to create salts. These salts will prevent water absorption, and cause other harmful biochemical reactions as well. It should not be much of a problem in small amounts, but letting it get out of hand will harm your plants.
If the label on your fertilizer lists something called ‘potash’, this is merely another name for the element called potassium.
Since it dissolves well in water, potash will usually need to be provided often and in different forms. Liquid potash comes in a convenient spray that can be used on the leaves or directly on the soil.
If you’re not sure of how much fertilizer is necessary, remember that you will do more damage by applying too much than too little. Start with a small amount and adjust it up from there. Usually your fertilizer will come with easy to follow directions that should help you get the mixture just right.