How to read a plant tag: zones, sun hours, size and spacing

Most tags carry the same few facts. The order changes from grower to grower and the back is often in small print, but you're looking for a name, a zone range, a sun label, a height and spread, and a spacing. The care notes help later, but these lines decide whether the plant suits your yard.

A tag that says zones 4 to 8 means the plant is expected to come through winter outdoors in zones 4 through 8. Your zone has to sit inside that range. The coldest number is the one that matters most where winters are hard; the warmest matters in the South, where some plants don't get the cold they need. If you aren't sure whether you're the colder a half or the warmer b half of your zone, Wisconsin Extension says to pick plants rated for the colder one.

Source: Wisconsin Extension, hardiness zone maps (Jull), checked October 11, 2026.

Sun words on a label stand for hours of direct sun in summer. University of Maryland Extension spells them out. Full sun is 6 or more hours, afternoon sun included. Part sun and part shade both mean 4 to 6 hours, with a difference: part sun plants can take some of those hours in the hot afternoon, while part shade plants want them before midday. Shade plants want no more than 4 hours, filtered or in the morning.

Source: UMD Extension Frederick County, sun on plant labels, checked October 11, 2026.

• 6+ hoursfull sun, afternoon sun includedUMD Extension Frederick County, sun on plant labels, October 11, 2026
• 4 to 6 hourspart sun or part shadeUMD Extension Frederick County, sun on plant labels, October 11, 2026
• 4 hours or lessshade, filtered or morning onlyUMD Extension Frederick County, sun on plant labels, October 11, 2026
• 5°Fbetween the a and b halves of a zoneWisconsin Extension, hardiness zone maps (Jull), October 11, 2026

A tag with two icons, say full sun and part shade, is telling you the plant will grow in either. The direction a bed faces gives a first guess: the Maryland article calls south the harshest exposure and north the kindest, with west getting the hot afternoon sun and east the milder morning sun. Trees and fences change that, so count the hours in the spot itself.

Source: UMD Extension Frederick County, sun on plant labels, checked October 11, 2026.

1. 1

   Know your zone first

   Look up your 2023 zone by zip code before you shop, and write it on your phone or a card in the car.

   Source: USDA Plant Hardiness Zone Map (2023), checked October 6, 2026.

2. 2

   Read the coldest zone on the tag

   If your zone is colder than the lowest number, the plant isn't expected to survive your winters in the ground.

3. 3

   Count the sun where it will go

   Note sun or shade in the spot in the morning, at noon and in the afternoon, then add up the sunny hours and compare them with the label.

4. 4

   Plan for the grown size

   Use the height and spread, not the pot, to decide where it goes. A small pot gives no hint of how wide the plant gets.

5. 5

   Space by the tag

   Measure center to center at the spacing on the tag. The gaps will look big in the first season.

6. 6

   Keep the tag

   Take a photo of the front and back, then note where you planted it on the log below.

The zone range on a tag is for plants in the ground. Roots in a pot sit in a small amount of soil that gets much colder than garden soil, so Illinois Extension says to choose plants that will survive two zones colder than where the pot spends the winter. For mixed pots, the Maryland article adds one more check: every plant in the pot should want the same light.

Source: Illinois Extension, overwintering potted plants, checked October 6, 2026; UMD Extension Frederick County, sun on plant labels, checked October 11, 2026.