FERTILIZERS - A FEAST FOR FOLIAGE
by Joelle Steele
Did you know that plants make their own food? Well, they do. They manufacture their own carbohydrates, fats, and proteins every day during a process called photosynthesis. So, if they make their own food, why do we have to feed them with all those different fertilizers? Well, we humans like our plants to grow fast, indoors, year round. And, when we grow blooming plants, we expect them to have lots and lots of flowers.
In their natural habitats, plants derive nutrients from soil which is almost always just right for their growing needs. That native soil is always being replenished with animal and vegetable matter that decompose into the soil, leaving it fertile and providing a veritable feast for foliage.
If you have all foliage plants, you can use any fertilizer that is formulated specifically for non-flowering houseplants. If you have flowering plants you will need a fertilizer just for blooming plants, and if some of those bloomers are African violets or orchids, you may also need a plant food that is specially formulated to meet their particular nutritional needs.
Whether you buy fertilizer that is organic or inorganic, in the form of a powder, a spike, or a liquid, is all entirely up to you. It just depends on what you feel most comfortable with. While some people will swear by liquid, others by powder, and yet others by time-release, the difference is really negligible and is just a matter of personal choice.
Once you decide on a fertilizer, it is important that you use it properly. READ THE LABEL. Do not ever use more than the label recommends. It is okay to use less, but most people err towards overfeeding which eventually results in small brown tips at the end of older leaves. Eventually, those brown tips can get pretty big and very unattractive and they are the result of the roots being burned by the excess fertilizers. This burning and the resultant damage will continue until those excess chemicals are washed out of the soil. Since it is often difficult to thoroughly drench an indoor plant without rotting the roots, it is better to err towards underfeeding. Better safe than sorry.
Indoor plants usually receive a lot less light than do your outdoor plants. Because of this, the plant is not manufacturing or using a lot of its own food. Therefore, if you add food, it may not even be used and may do more harm than good. In most cases, lightly fertilizing your foliage plants once or twice a year during spring or early summer is more than sufficient. Ditto for your flowering plants.
When applying fertilizers, always apply them to moist soil, even if you are applying a liquid or powder fertilizer that you have just mixed with water. Do not let any of the substance get on the stems of the plants as the chemicals in the fertilizer can cause damage to the plant tissues. Apply the fertilizer evenly over the entire soil surface so that it will reach down into the entire root system of the plant and not just into one area.
This article last updated: 09/03/2004.