USDA Growing Zones Explained: How to Pick Plants That Actually Survive

Every gardener has killed a plant they shouldn’t have bought. You picked it up at the nursery, it looked great, the tag said “perennial,” and it was dead by February.

The problem wasn’t your thumb. It was your zone.

What is a growing zone?

The USDA Plant Hardiness Zone Map divides North America into 13 zones (1a through 13b) based on the average annual minimum winter temperature. Each zone represents a 10-degree Fahrenheit range.

• Zone 3: -40F to -30F (Minnesota, Montana)
• Zone 5: -20F to -10F (Iowa, Ohio, Colorado)
• Zone 7: 0F to 10F (Virginia, Oklahoma, parts of Oregon)
• Zone 9: 20F to 30F (Florida, Southern California, Louisiana)
• Zone 10: 30F to 40F (South Florida, Southern Arizona)

Your zone tells you which plants can survive your winters. A plant rated for zones 5-9 will grow in Virginia (zone 7) but die in Minnesota (zone 3).

How to find your zone

The easiest way is to search your zip code on the USDA’s interactive map. But here’s a rough guide:

• Northern states, mountain areas: Zones 3-5
• Mid-Atlantic, Midwest, Pacific Northwest: Zones 5-7
• Southeast, Southern Plains: Zones 7-9
• Gulf Coast, Southern California, Florida: Zones 9-11

Note: zones can vary within the same city. Urban areas tend to be one zone warmer than surrounding rural areas (heat island effect). Elevation matters too — higher elevation means a lower zone.

Zone is necessary but not sufficient

Knowing your zone tells you what can survive, but not what will thrive. Two other factors matter just as much:

Heat tolerance. Zones measure cold hardiness. A plant rated zone 5-8 can handle zone 5 winters, but the “8” tells you it may struggle in zones above 8 where summers are too hot.

Chill hours. Many fruit trees and berry bushes need a certain number of hours below 45F to produce fruit. A peach tree that needs 800 chill hours won’t fruit well in zone 9 even though it can “grow” there.

Microclimate. Your specific yard matters. South-facing walls are warmer. Low spots collect frost. Shaded areas stay cooler. You might be zone 6 on the map but have a zone 7 microclimate against your south-facing brick wall.

Variety matters more than species

This is where most gardeners go wrong. They look up “can I grow tomatoes in zone 6?” — and the answer is yes. But which tomatoes?

Some tomato varieties need 90+ days of heat. Others produce in 60 days. In a zone 6 garden with a shorter growing season, the variety choice makes the difference between a harvest and a disappointment.

Same for fruit trees. You can grow apples in zone 5, but not every apple variety. Some need pollinators you may not have. Some are disease-prone in humid climates. Some need more chill hours than your area provides.

The variety is as important as the species.

How to match varieties to your zone

For each plant you’re considering, check:

1. Hardiness zone range — Will it survive your winters?
2. Days to maturity — Does your growing season give it enough time?
3. Chill hours (for fruit) — Does your area get cold enough?
4. Disease resistance — What’s common in your climate?
5. Pollination needs — Does it need a partner variety?

This sounds like a lot, but it’s the difference between a garden that produces and one that just… exists.

The easy way to match

HooGrew is a variety-level growing guide that answers all of these questions. Search by plant type, filter by your zone, and get specific variety recommendations with pollination data, disease resistance, soil needs, and spacing requirements. No sign-up, no cost — just the information you need to pick the right plant the first time.