Growing Karl Forester Grass in containers
Hello! I have found myself with extra Karl Forester Grass and would like to grow it in containers. How can I keep these alive through the winter? I could move them inside, and have both heated and unheated buildings available. When should they be trimmed back? Should it be watered through the winter? How deep must my containers/soil be? I typically use crushed cans in the bottom of my pots so I don't need so much potting soil, and to make the containers lighter, but perhaps a perennial grass needs more soil to establish its roots. I would be interested in any information about growing perennials in containers, but specifically Karl Forester grass at this time. Thank you for your advice!
Spink County South Dakota
You need a large sized container for the grass. The grass should be planted to the depth that it is in the existing container. You need plenty of soil for the grass root ball. Do not put crushed cans or other material in the bottom of your pots as that would be detrimental to the plant. Karl Forester grass should be kept outside through the winter, it is a deciduous grass and needs its dormant period in order to do well. If you cannot bury the pot in the soil you need to find someway to insulate it so the roots do not freeze. The foliage of the grasses make a good winter presentation. It should be cut back just prior to new shoot growth in early spring.
You can grow perennials that are hardy in your zone in containers and put them in the soil in the fall to winter over either in or out of their pots since they too need the dormant time. Since the plants are not in the soil they will need you to attend to their water and basic nutrition needs. I am attaching a link on containers preparation.https://igrow.org/gardens/gardening/do-you-need-a-thriller-in-your-garden/
Thank you for your reply. What might you suggest to insulate the pot through the winter? I don't have any kind of a flower bed deep enough to bury a pot.
Thanks so much!
Straw or straw bales arranged around the container would work or any heavy mulch can be used. Spink county appears to be mainly in Plant hardiness Zone 4a with temperatures of -30 to -25 in the winter. If there is a nursery near by you might check to see how they insulate their plants in the winter. I hope this helps.