USDA Hardiness Zones are a gardener's cheat sheet for winter plant survival. Each zone is determined based on the coldest average winter temperature in that area. Keep in mind that these zones only measure cold tolerance, and that there are other factors that affect plant success such as:

• Sun vs. shade

• Soil type and drainage

• Moisture levels

• Wind exposure

• Microclimates

Microclimates are areas that are either warmer or cooler than the surrounding area. This can affect the success of some plants, reguardless of what USDA zone you are located in. In some cases, it can allow gardeners to push plant limits!

Examples:

• 1. South-facing walls: Reflected heat can help support plants that prefer warmer conditions, but it may stress plants that are sensitive to heat.

  2. Sheltered garden beds: By blocking wind, capturing the sun’s warmth, and helping water drain properly, these features make life easier for your plants - creating warmer, more stable, and less drying conditions. You can achieve this with walls, fences, or hedges.

  3. Low spots: Often called “frost pockets" - when cold, heavy air naturally sinks into these areas at night it can’t escape, meaning that these spots stay colder than the surrounding higher ground. That means plants in these low spots might see fall frosts earlier and spring frosts later than those planted just a few feet away.

  4. Urban heat effects: Dark, dry, and impervious surfaces (i.e asphalt and concrete) absorb, store, and radiate more heat. Gardeners who live in urban areas may expereince warmer microclimates due to this effect. Rock mulch, sidewalks, and driveways will also radiate extra heat, even in rural areas.

When choosing plants, take a moment to read the plant label or description, which usually lists the plant’s recommended hardiness zones.

For the best results, select plants that are suited to your zone or even one zone hardier, giving them a little extra buffer during harsh winters. Check out our blog on Fall/Winter Garden Prep for helpful tips on overwintering tender perennials!

It’s also helpful to prioritize native or regionally adapted plants, since they’re naturally suited to your climate. They tend to establish themselves quicker, support local wildlife better, and thrive with less maintenance. Read more about Minnesota Native Perennials.

By embracing the idea of right plant, right place and working with nature instead of against it, we create gardens that grow stronger, more vibrant, and more resilient with every season!