Metal plant markers help gardeners identify each particular species of plant while also staving off elements that degrade other plant markers made of wood, plastic or clay. Metal plant markers can be etched or embossed to provide a description that won't erode from exposure to water, air and soil.
Effective metal plant markers are made of a moisture-resistant metal or metal alloy to prevent oxidation. Many metal plant markers use stainless steel because the alloy is sturdy and resists rust. Copper is another metal typically used in metal plant markers, and it is also valued for its aesthetic quality. While resistant to most corroding climates, copper tends to be more malleable than stainless steel.
A metal plant marker is especially useful in marking vegetation not easily identifiable, such as bulbs that won't produce any visible evidence of vegetation until several months after planting. Temporary markers often fade or break after a season exposed to the elements.
Many metal plant markers require engraving or the use of a lacquer pen, which makes labeling more difficult than what is typically required of wood or plastic markers. Because of the cost of the material used, metal markers are often more expensive than other markers.