Containers: Not Just for Annuals
Many gardeners love to display annuals in containers for spring, summer, and fall. Some also know that quite a few of these plants, although not hardy enough for a Minnesota winter, are actually tender perennials or shrubs that can be overwintered indoors. Examples include spikes, begonias, lantana, and flowering maples.
Although less widely used, there are also hardy perennial plants that work well in containers. The U of M says that no potted plant can survive a Minnesota winter “without significant protection,” so any gardener who doesn’t want to simply toss the plant at the end of the season needs to replant it into the ground in time for it to settle in before winter’s cold arrives. (Indestructible chives are a notable exception).
Why would we want to do such a high-maintenance thing?
- Hardy plants can look novel in a container.
- They might be plants you want to keep an eye on or protect from rabbits or dogs.
- They might be edibles you want to have within easy reach instead of at ground level.
Any of the Boulevard series of clematis, including our new offerings Alaina, Cezanne, and Neva, (C040, C043, C058), have been bred for compactness and would be excellent in a container this year, then moved to a permanent location in the yard.
Shrubs and trees
Similarly, a shrub such as the 2’ globe of arborvitae Linesville (S005) or the exclamation point of arborvitae De Groot’s Spire (S009, eventually 7’, but not in its first year) make interesting additions to a large pot. The will also keep them out of reach of hungry rabbits. More shrubs that are worth trying in a container:
- Boxwood Chicagoland Green (S031, 3–4’)
- Hydrangea Invincibelle Mini Mauvette (S093, 2–3’) (easier to acidify the soil in a pot)
- Lilac Bloomerang Dwarf Pink (S109, 2.5–3’)
Small garden plants can start in a trough or fairy garden container, then be moved to a garden bed in fall. One example is Cotoneaster Tom Thumb (M008, 6–12”h).
- Gasana strawberry (F096) with its large pink flowers is pretty enough to be displayed in a container.
- Alpine strawberries such as Alexandria and Yellow Wonder (F104 and F105) are easier to pick in an elevated container.
- Coral Bells such as Primo Black Pearl (P128, 8–10”) provide unusual, dramatic foliage for a container.
- Hostas (page 25) can survive winter in a pot or trough (some can survive the winter when just dug up and set on top of the ground!). Hostas look excellent at eye level or even higher. But to be safe over the winter, cover or move their containers to a more protected spot. One miniature hosta is Munchkin Fire (P277, 7”).
Other hardy plants can work, too. Just make sure they aren’t ones with a taproot or that are known to dislike being replanted.