Back when I was a younger gardener, we lived in a small town in Colorado. The local nursery didn't offer a very wide selection of plants, or maybe I just didn't know what to look for. So I ended up planting a hybrid tea rose each spring, just to discover that it was dead the following year.
It wasn't until we moved to Utah that I started growing plants from seed. Now I have hundreds of seed-grown perennials. Of course, we live in zone 5b, so I have a greater selection of plants than I could have grown in Colorado's zone 4. I'm grateful for that, but sometimes I think about what I would grow if I ever moved to a colder zone. Colorado is a beautiful place to live. So this article is dedicated to gardeners in zones 3-4.
If you don't know which zone you are in, click here for a hardiness zone map. Or call your local extension service. You can also find out your zone by becoming a member of Dave's Garden. That's where I get most of my information on the hardiness of individual plants.
Of course, I don't believe in restricting myself to the plants that are hardy in my zone. All good gardeners like to push the limits. For example, I have succeeded in overwintering plants that are only hardy to zone 6 or 7 by growing them against a south-facing wall. Mulching the garden with wood chips also helps to protect plants from the cold.
All of the following plants should grow in zone 4. The hardiest perennials can be grown in zone 3.
Perennials for the Coldest Zones
Annuals for the Coldest Zones
Rather than give a long list, I'll just make some general recommendations. Practically all of the annuals on this website can be grown in zones 3-4, but some are easier than others. In general, gardeners with short growing seasons should select annuals that bloom quickly from seed. Self-sowing annuals are my favorites because they come back the following year from seeds that drop to the ground at the end of the season. When growing annuals that bloom late in the season like cleome, cosmos and zinnias, it's best to start the seeds early indoors.
