From our newsletters:
We have given quite a bit of thought to which grasses are appropriate for growing in containers. We have not tried all of these, however in coming up with this list we have considered things such as:
- how fast the root system grows
- how well the plant adapts to being pot bound
- height of the plant (most grasses will be smaller in containers)
- how it looks throughout the gardening season
When choosing grasses for containers, it helps to keep in mind that cool season grasses will grow and bloom earlier in the season. With warm season grasses often the main feature is their blooms and since they bloom late in the season, one might want to think of them as late-season containers. Combining warm and cool season grasses in the same container will provide a longer season of interest. Carex flagellifera doesn't really bloom, but with its tan-colored foliage, provides great contrast.
Want to keep the containerized plants over the winter?
A plant kept in a container over the winter will loose 1 to 2 zones of hardiness. That means that a grass hardy to Zone 3, such as Calamagrostis x acutiflora 'Karl Foerster' should be able to survive the winter above ground in a pot in Zone 5. If you can't keep it in a warmer location for the winter, then try packing bags of leaves around and above the pot. Or you could dig a hole in the ground and place the plant in it (it is highly recommended that the plant be removed from the pot first). Be sure to water the plant in so that the soil settles in snugly around the root mass.
Please note that many grasses will flop if they are fertilized, so these are not to be treated with too much TLC!
If you are planning on combining different grasses in the same container they should have the same moisture needs. Please refer to the individual plant's webpages or to our Grass Comparison Chart to determine which plants will work with each other.
The Festucas are, for the most part, small grasses that work well in containers. However due to their tendency to soak up all the available water before other plants can get their share, we recommend that they be put in their own pot. Also, their nice form and flowers are best appreciated when they are alone in a container.
Here are some grasses we suggest that you might try in containers:
Suggested Cool Season Grasses:
- Achnatherum calamagrostis - large container
- Alopecurus 'Variegata' - for part shade
- Andropogon 'New Wave' - large container
- Anthoxanthum odoratum (Vanilla grass) - smells wonderful
- Calamagrostis 'Avalanche' - fairly large pot
- Calamagrostis 'Karl Foerster' - feather reedgrass - large container
- Calamagrostis 'Overdam' - fairly large pot
- Carex 'The Beatles' - good for part shade
- Carex 'Beatlemania' - good for part shade
- Carex davalliana
- Carex dipsacea
- Carex grayi - shade plant
- Carex flagellifera - being a tan-colored plant, it adds wonderful contrast
- Carex 'Kiwi' - has kiwi-green colored foliage
- Carex 'Little Midge' - small plant, likes moisture and some shade
- Carex 'Variegata' - good for a bog container
- Chasmanthium - happy in a slightly shady spot
- Deschampsia 'Goldtau' - compact plant
- Festuca Elijah Blue' - blue foliage, small plant, see paragraph above
- Festuca 'Select' - blue foliage, small plant, see paragraph above
- Festuca 'Boulder Blue' - blue foliage, see paragraph above
- Festuca idahoensis 'Siskiyou Blue' - blue foliage, see paragraph above
- Festuca mairei - medium green foliage, large container, see paragraph above
- Festuca 'Nefer' - see paragraph above
- Helictotrichon sempervirens - blue foliage, larger than blue fescues
- Juncus ensifolius - great in a bog container
- Juncus 'Spiralis' - great in a bog container
- Juncus 'Lovesick Blues' - great in a bog container
- Koeleria vallesiana 'Mountain Breeze' - light on the fertilizer; do not overwater
- Molinia 'Poul Petersen' - needs a large and deep container
- Molinia 'Strahlenquelle' - medium-sized grass
- Molinia 'Variegata' - fairly small, variegated
- Sesleria autumnalis - blooms in the fall
- Sesleria albicans - in hot dry conditions, provide some shade and extr water
- Sesleria caerulea - blooms first thing in the spring, foliage is always nice
- Sesleria heufleriana - same as above
Suggested Warm Season Grasses:
We would love to receive feedback from those of you who have grown plants in pots. This will help others to be successful.
From J. Cosentino, Boston, MA, Zone 5/6:
"Calamagrostis 'Overdam' does wonderfully in pots. I have had 2 plants in a 3'x18"x18" trough and they have survived the winters and thrived. Miscanthus did well in the summer but did not survive the winter, though I didn't do anything to protect it. I am going to try the hardier Miscanthus purpurascens this year."