Ornamental Grass Maintenance - Ask Extension
I have a couple of questions about the long term care of Calamagrostis acutiflora "Karl Foerster" feather grass. The center of the grass has died ou...
Knowledgebase
Ornamental Grass Maintenance #443093
Asked March 10, 2018, 9:59 PM EST
I have a couple of questions about the long term care of Calamagrostis acutiflora "Karl Foerster" feather grass. The center of the grass has died out. Based on Plantalk #1068 it appears this is an indicator that the plant needs to be divided. Does this happen faster if the growth is limited by landscape fabric or is it based on age? Is the center dying accelerated by more or less water? Can I excavate the plant, remove dead sections and compress remaining healthy roots into one bunch to maintain plant size and replant or do the divisions need to be smaller? Since this is a cool season grass I assume it should be divided in the Fall but can it survive an early spring division done in March? Can I use a post hole digger and take out the center of the plant and replace with new soil? I have a group of about 30 plants that are 9 years old. Some are doing excellent but many are dying in the center. Looking for help to know how to maintain all of them at the same size and health. thanks
Douglas County Colorado
Expert Response
Hello,
Karl Foerster feather grass grows at a medium rate, and under ideal conditions can be expected to live for approximately 10 years. There are many factors ( not one specific factor ) that effects growth of plants such as sunlight, soil condition, age of plant and weather patterns. You can start dividing the Karl Foerster feather grass once you see it starting to show new signs of life ( new growth ) in early spring. To divide-dig the entire clump up from the ground. Use a sharp spade, a large knife, an ax to cut through the core and halve the clump completely. Then proceed to quarter it. Separate living divisions from dead tissue by hand and make sure each division has a good root system still attached. Replant divisions as soon as possible, water well, and protect with mulch up to 3″ deep.
Karl Foerster feather grass grows at a medium rate, and under ideal conditions can be expected to live for approximately 10 years. There are many factors ( not one specific factor ) that effects growth of plants such as sunlight, soil condition, age of plant and weather patterns. You can start dividing the Karl Foerster feather grass once you see it starting to show new signs of life ( new growth ) in early spring. To divide-dig the entire clump up from the ground. Use a sharp spade, a large knife, an ax to cut through the core and halve the clump completely. Then proceed to quarter it. Separate living divisions from dead tissue by hand and make sure each division has a good root system still attached. Replant divisions as soon as possible, water well, and protect with mulch up to 3″ deep.
