Do Miracle-Gro Fertilizer Spikes Harm Plants?

Growing lush, beautiful plants involves more than simply watering them occasionally. Plants can benefit from the judicious use of a little fertilizer. Deciding which type and how much to use can be confusing. Chemical fertilizers like Miracle-Gro are available in granular, liquid and solid form. The solid fertilizer is often in the form of pre-measured sticks called spikes. These are inserted into the soil next to the plant for time release.

According to the Miracle-Gro official website (scotts.com), using this product as directed on the packaging will lead to larger and better producing plants and flowers. The ingredients in Miracle-Gro are ammonium phosphate, ammonium sulfate and potassium chloride. While generally considered safe if handled carefully, these chemicals should not be ingested or breathed. Be sure to wash your hands after you have handled the fertilizer spikes. Phosphorus, potassium and nitrogen are the three main nutrients every plant needs. The Scott’s company products contain chemically derived versions of these. Miracle-Gro spikes provide food for your plant in a form that you only have to replace monthly during the growing season and bi-monthly in the fall and winter. While phosphorus is important to plant health, there is debate as to the long-term effect of ammonium phosphate on soil condition. In other words, the spikes may provide you with a bountiful harvest of blooms or vegetables, but the soil may eventually be depleted rather than fed by this formula. You may have to improve your soil even more in succeeding seasons. The website davesgarden.com says: "Soil fertility authority Garn Wallace, Ph.D., of Wallace Laboratories in El Segundo, California, points out that Miracle-Gro contains muriate of potash [their version of potassium], which contains excess chlorine that will burn plants and inhibit the uptake of nitrogen." According to the U.S. Golf Association’s Turf site (turf.msu.edu), ammonium phosphate will ensure that worms will not survive in your lawn, and if it isn’t watered in thoroughly it will burn your grass. Chemical fertilizers tend to burn plant root systems and leaves if they are applied too heavily or not diluted well enough, as seen on package warnings.

Now if you are going to use the spikes for your indoor potted plants, and are not growing food in a large garden spot, the Miracle-Gro plant food spikes will most likely prove to be a good product for you. They don’t seem to damage the plant itself unless they are used incorrectly.