The best time to plant roses is springtime, after the danger of frost has passed. There are several reasons for this:
- Bare root roses and many new container roses are available from growers and garden shops in springtime
- The soil is soft enough and warm enough in springtime to encourage growth
- Roses are coming out of their dormant period due to increased hours of sunlight and higher temperatures
Availability of roses
Because roses go mostly dormant in late fall and winter, growers plan their new commercial offerings to be available in spring. Garden shops, big box stores with garden centers, and online sellers will have a big variety of roses available starting in February-March (in the northern hemisphere, September-October in the southern hemisphere).
My spring may not be your spring
When spring happens varies, depending upon where in the world you live, of course. You’ll need to take that into consideration before planting roses. But, if roses aren’t available locally or online, you can bet that it’s not a good time of year to plant in your locale.
Growing indoors first
That said, it is possible to purchase roses from some growers who breed their roses in greenhouses. If you plan to grow your roses indoors, for example, in a greenhouse or in an enclosed patio, then planting times aren’t as important. You may, however, still have trouble finding the varieties you want, because growers will aim to have the widest variety and number of roses available for the most popular purchasing and planting season.
The USDA zone system
In the United States, we follow a zone system, which indicates a variety of conditions, one of which is temperature. You can see on the map from the USDA Agricultural Research Service that most zones in the lower 48, as well as partial zones in Alaska and Hawaii, can support roses, even through the winter. Keep in mind, in the lower zones (1-2), you should mulch your roses or even cover them during the winter to protect them from extreme chill below -40 F. The best thing to do is check with your local rose society, if there is one, or with your agricultural extension department in the fall. See below for links to global hardiness zone information.
Soil temperature and workability
If you’ve ever tried to dig a hole in a frozen garden, you’ll already know why spring is the best time to plant roses, in most areas of the northern hemisphere. While you can plant roses in the fall, well before the first frost (6 weeks), you will see little growth and blooming until the following spring.
Planting roses in the fall works, but is tricky
The concern I have about planting in the fall is that once the bushes go dormant, and you’ve finished your winter pruning, you can’t tell how well the bush is doing underground for several months. Once spring rolls around, the bush might be fine, or it might have succumbed during the winter, because it wasn’t able to establish enough root mass in the short time before going dormant. If it doesn’t make it, you’ve got an empty spot in your garden. And, you’ll need to purchase another rose to put in its place.
If you live in warmer climes
That said, if you are an experienced gardener, you may not worry about this. Also, if you live in a fairly warm location where winter temperatures vary only by single digits and frost is not an issue, you probably won’t run into any issues with planting in the fall.
Like many plants, roses go dormant in the winter. I understand from some of my more knowledgeable rosarians that roses never go fully dormant, especially if you consider that deep in the soil, their roots are still working, albeit very, very slowly. Roses begin to go dormant as the temperature drops. You and I might not notice this much in the fall, other than a bit of chill in the evening or morning, but the soil and air temperature around your rose bush starts to drop degree by degree as fall proceeds toward winter.
Plants are complex
Plants have many complex mechanisms that react to specific environmental signals, mainly temperature, availability of water, and daily dose of sunlight. In the northern hemisphere, as the sun begins to set earlier, roses are exposed to less sunlight each day. The diminishing sunlight and the drop in temperature triggers dormancy. The plant begins to store nutrients in its roots and lower trunk, just like our blood begins to gather around our vital organs when we get cold. And, just as our fingers and toes begin to tingle and lose feeling, so do the stalks on your rose bush. Flowers and new growth stop, as there is no longer enough sunlight or nutrients to support new growth and blooming.
Combination of reasons
So, you can see that a combination of reasons make it ideal to plant roses in spring:
- Availability of robust and new varieties from growers and garden shops
- Beginning of the growing cycle in many locations
- Workability of soil
- Availability of sustained sunlight and warmth
Yes, you can plant indoors, you can plant in fall, but if you want to give your roses the best possible chance to succeed and thrive, try planting in spring, after all danger of frost has passed.
For more information about hardiness zones in locations outside of the continental USA, visit the resources below: