Three materials, three failure modes. Plastic fades, aluminum flattens, and stainless costs more. Which one you want depends on what the tag is for and how long the tree will be there.
Plastic
Every nursery tree arrives with one. It’s cheap, printed by machine, and looped on with a plastic tie. It’s also the label you’ll lose first.
Sunlight does most of the damage. UV breaks the plastic down within a couple of years, and the print on it goes sooner: the pigment sits on the surface, so it bleaches long before the tag itself gives out. The tie is the other problem. It’s a closed loop that doesn’t grow, and a branch that fits it at planting will be strangled by it three seasons later. Most growers cut the tag off to save the branch, and that’s the moment the variety name leaves the tree.
Marker on a plastic strip is the DIY version of the same thing. Free, quick, and readable for a year or two if the strip is in shade.
Plastic is fine for annuals and bedding stock that’ll be gone by autumn. It’s the wrong material for anything that stays in the ground.
Aluminum
Aluminum is the right choice for some jobs. It doesn’t rust, it grows its own oxide skin, and it’s soft enough to emboss with a hand tool in the field. A numbered aluminum disc nailed to a trunk in 1998 is usually still readable. In quantity it costs well under a dollar a tag.
Two things go wrong with it.
The softness that makes it easy to emboss also makes it easy to flatten. A branch, a hailstone or a string trimmer pushes the digits back out, and embossed text shallows a little more every year it rubs.
The other is chemistry. Aluminum doesn’t like alkalinity and chloride together, and that’s a fair description of an orchard: fertilizer salts, irrigation water, coastal air. It pits. Hang it on a galvanized nail and it goes faster, because in a galvanic pair aluminum is the one that gives.
Then there’s the anodized kind, the custom-printed metal plant tags most people buy online. The laser doesn’t cut the metal on those. It strips the colored dye off the surface, so the text is a color contrast, and it fades at the same rate as the background it sits on. They run $3.99 to $5.99 a piece and usually carry a minimum order per design.
If what you need is a number that points at a row in a spreadsheet, buy aluminum. There’s more on where it wins and where it doesn’t in aluminum tree tags versus stainless steel.
Marine grade stainless steel 316L
Not all stainless survives a garden. Ordinary 304 pits when chlorides attack it: coastal air, fertilizer salts, orchard sprays. 316 adds molybdenum, the marine-grade defense, for roughly a third more pitting resistance. It’s the grade specified for boat fittings.
The L matters too. Laser marking heats the mark zone through the range where stainless loses chromium to grain-boundary carbides and can rust along the text itself. Standard 316 starts to sensitize after minutes at that temperature. Low-carbon 316L needs tens of hours at the same heat, and an engraving pass lasts a fraction of a second, so the text keeps the same corrosion resistance as the metal around it.
The bigger difference isn’t the alloy. It’s what the laser does. On plastic and anodized aluminum the text is printed or dyed on top. On our tags it’s cut in: the beam takes metal out, and there’s nothing left to fade or flatten. No ink, no coating, no pigment budget being spent.
Our tags are 316L, 75 by 25 mm, three lines of your own text: $2.99 each, $2.49 from 10, and $1.99 in quantities of 50 or more. Every tag in an order can say something different.
Which one to buy
| You are | Buy |
|---|---|
| Labeling bedding stock or annuals | Plastic, and throw it away with the plant |
| Numbering trees for a survey or inventory | Aluminum |
| Tagging a research plot on a budget | Aluminum |
| Naming a tree you’ll still own in twenty years | 316L stainless |
| Labeling an orchard on a coastal or high-fertilizer site | 316L stainless |
| Running a nursery where the customer reads the tag | 316L stainless |
Short version: if the tag holds a number, buy aluminum. If it’ll be gone by autumn, plastic is fine. If it holds the only record of what the tree is, it has to outlive the tree, and that’s a different piece of metal.
Whichever you choose, hang it so it can’t girdle the branch.