Feather reed grass is one of the best ornamental grasses to include in your garden if you are looking for something that is going to add year-round interest to your outdoor spaces.
This clump-forming grass species is popular because it stays upright throughout the year, it is easy to grow and it can be used in containers or garden beds. It can even be used around water features like ponds or lakes because the grass variety can tolerate relatively dry to almost wet soils.
These perennial evergreen grasses require very little maintenance but they should be grown under the right conditions or they won’t develop well. In this guide, we are going to share everything you need to know about taking good care of this infamous grass variety.
|Feather Reed GrassKarl Foerster Grass
|Height and Width
|2 – 3 Feet tall and 5 – 6 feet tall flowers and stems, 2 feet wide
|Europe and Asia
|White to reddish-white flowers or plumes with pinkish-tan to wheat-colored seed heads
|Full sun with afternoon shade in warmer regions
|Soil Type & pH
|Any moist but well-drained soil (Including chalk, clay, loam, and alkaline to acidic soils)
|Cut flowers, Good for Containers, Low Maintenance, Multi-seasonal interest
What Does Feather Reed Grass Look Like?
This ornamental grass variety will add lots of vertical interest to your garden spaces because it grows in clumps that stay upright throughout the year.
The cool season grass can look a little bit different during different growing stages.
New growth emerges in early spring and the grass will quickly develop slender blue-green leaves that can shoot up to 3 feet tall.
From summer to fall, these grasses will produce taller flower stalks of up to 6 feet with pink, purple, or white plumes. The delicate flowers can add lots of color and fine texture to your garden until they transform into seed heads.
The seed heads usually start appearing in fall and can give the grasses a grain-like appearance. At first, the seed heads will be pinkish-tan in color but in late winter, they will transform into golden wheat hues.
The grass stalks will create a striking effect in winter because they will stay upright even though the leaves will turn golden wheat colored. These stalks can be pruned in late winter and used in flower arrangements, or so the new growth can develop quicker when spring arrives.
Where Does Feather Reed Grass Grow?
Feather reed grass is a hybrid grass that resulted from crossing two species of grasses that are native to Europe and Asia. This grass variety is grown in many different countries but will only survive in Mediterranean climates but it prefers cooler areas.
Common feather reed grass is quite flexible since it can tolerate most soil types as long as it drains well and can be grown in relatively dry to almost wet soils.
This ornamental grass won’t grow in waterlogged conditions and it does require a full sun position or it will flop over or might not flower.
You can grow this grass directly in a garden bed or even mass plant it in open prairies and it will also take well to containers.
How Fast Does Karl Foerster Grass Grow?
Karl Foerster grass grows at a moderate to rapid growth rate, especially when growing conditions are favourable. Despite its rapid growth, it is not considered invasive.
How To Grow Karl Foerster Grass
If you want your grass to flourish then you should plant it in the right conditions. Here is a quick look at the right planting methods for this ornamental grass.
Feather reed grass can be propagated by dividing the plumes every three to five years.
These ornamental grasses grow and spread through rhizomes. The clumps will keep getting larger and should be divided from time to time so the clumps won’t become too dense. If the clumps are too dense, it might block out sunlight and airflow which these plants need to grow healthily.
The best time for propagation is usually in the fall or spring.
These beautiful grasses can tolerate a wide range of soil types but they prefer well-drained soil that is kept consistently moist.
These grasses will grow well in loam, chalky, or even clay soil types but can develop root rot if the soil doesn’t drain well.
You also don’t have to monitor the pH level of the soil because it can grow well in neutral, alkaline, or acidic soils.
Some researchers also believe that feather reed grass can promote soil because it is useful for the phytoextraction of heavy metals.
This grass variety will stay upright and will look neat even when the leaves or seeds dry out for winter. Because the grass still offers lots of winter interest in this dry state, most gardeners will wait until just before new growth emerges before they prune back the old foliage.
This is usually done in late winter or early spring and gardeners usually cut the grass to the ground at this stage.
Repotting and Transplantation
If you want to repot feather reed grass or transplant it in different garden beds then it is best to wait until the plumes start to grow vigorously again. This is usually in early spring.
Start by extracting the rhizomes from the soil. You can now divide the plumes and clean the roots but try to keep the root system as much intact as possible and prune back any rotting roots.
It is best to plant it in a prepared garden or pot with organic fertilizer and permeable soil.
Water the plant thoroughly right after planting and keep it moist for the first week.
Karl Foerster Grass Spacing
Karl Foerster grass grows to a height of 36-60 inches and a spread of 24-36 inches. As a result, it is critical to provide enough space for the grass to develop without crowding out other plants or structures.
Karl Foerster grass is normally spaced between 18 and 24 inches apart. This permits the grass to grow and spread without encroaching on the plants around it. It also ensures that the plants have enough space to spread out and get enough sunlight and nutrients.
How to Care for Feather Reed Grass
This low-maintenance grass is very easy to care for. Let’s take a quick look at these feather reed grass care tips.
This grass variety can survive dry spells but it grows best if it is regularly watered or in moist soil. The plant prefers regular watering but it shouldn’t be watered too deeply. As a rule of thumb, you can water it twice a week or more often in extreme heat situations.
If you want this grass to stay upright and produce viable seed and plenty of flower stalks then you should plant it in full sun with a minimum of 6 hours of direct sunlight per day.
These grasses will appreciate some afternoon shade if grown in warmer regions. But if it receives too much shade, it won’t flower and the leaves will become floppy and can topple over. The growth will also be stunted in a shaded position.
Temperature and Humidity
The cool season grass cannot tolerate intense heat but it can survive temperatures below freezing point.
If the grass is planted in warm regions, it should be placed where it will receive lots of afternoon shade. In colder regions, you can also place a layer of mulch over the soil to insulate and protect the grass from frost.
These vivid grasses can tolerate various humidity levels but it does need good air circulation around its base or it can develop problems.
There is no need to add fertilizer to the pots or soil because the grass can tolerate poor soil conditions. If you are worried that the nutrients might not be sufficient then you can just add a bit of organic mulch on top of the soil or mix in some plant food.
Pests and Diseases
This grass variety has very few pests and diseases. There are only three common problems to look out for with these beautiful grasses.
Aphids are sap-seeping pests that can infest and overcrowd plants. They typically focus on soft or new growth and can affect the growth of the plant since new spots won’t develop well.
Spider mites can appear like dust on the plant leaves and usually occur when the plant is suffering from water stress.
These disease problems are caused by a fungus and usually occur when there is water on the surface of the leaves. You can avoid rust by adding water around the base of the plant instead of sprinkling it all over.
Feather Reed Grass Companions and Landscaping Ideas
Many plants can look striking alongside feather reed grass but it is best to select species with similar growing conditions.
Here is a quick look at the top companion plants for feather reed grass.
- Other ornamental grasses like Elijah blue fescue grass or Karley rose fountain grass
- Ornamental flowering species like Russian sage, black-eyed susans, or blonde ambition
These companion plant species can be used in different ways to create all sorts of creative and beautiful landscaping effects like the following.
A mixture of different potted flowers and ornamental grass species positioned together will look rather striking in your garden.
Ornamental grasses and tall flowers can be mixed alongside roads, driveways, or walls to create showy mixed hedges in cottage gardens.
Common Varieties and Cultivars
Feather reed grass is a cross between two different grass varieties. The grasses do however come in a couple of varieties like the following.
- Calamagrostis x acutiflora ‘Karl Foerster’
- Calamagrostis x acutiflora ‘Overdam’
- Calamagrostis x acutiflora ‘Avalanche’
This low-maintenance grass is, without a doubt, one of the best varieties to grow in colder regions because it will bring you lots of cheer with its interesting colors. We hope that our guide gave you lots of helpful tips on the best way to keep your feather reed grass as healthy and beautiful as possible.
Susan Mahr, Feather Reed Grass, Calamagrostis x acutiflora ‘Karl Foerster’ – https://hort.extension.wisc.edu/articles/feather-reed-grass-calamagrostis-x-acutiflora-karl-foerster/
Linda Naeve, Feather reed grass: a special landscape feature – https://hortnews.extension.iastate.edu/1997/4-11-1997/featherreed.html
North Carolina Extension Gardener Plant Toolbox – Calamagrotis x acutiflora – https://plants.ces.ncsu.edu/plants/calamagrostis-x-acutiflora/
Elizbieta Rolka, Miroslaw Wyszkoski, Radolsaw Szostek, Alicja Glika – Role of feather reed grass in phytoremediation of urban soils – https://pubmed.ncbi.nlm.nih.gov/36029005/
*image by Vejaa/depositphotos