How big does Feather reed grass 'Karl Foerster' grow?

About 1.5 m × 75 cm after ten years (height × width). Its ultimate size is 0.9–1.5 m × 45–75 cm.

What soil does Feather reed grass 'Karl Foerster' grow in?

It tolerates these soils: average garden soil, clay, sandy, calcareous, acidic.

Is Feather reed grass 'Karl Foerster' hardy?

Hardy down to -29 °C (USDA zone 4, RHS H7). It gets through winter in every part of the country.

When does Feather reed grass 'Karl Foerster' flower?

Flowering: June–August, pink, purple.

How much water does Feather reed grass 'Karl Foerster' need?

Water need: medium. Drought tolerance: medium.

Feather reed grass 'Karl Foerster'

Calamagrostis × acutiflora 'Karl Foerster'

Feather reed grass 'Karl Foerster' (Calamagrostis × acutiflora 'Karl Foerster') is an ornamental grass that reaches 1.5 m × 75 cm after ten years. Light: full sun, part shade. Hardy down to -29 °C. Drought tolerance: medium. Sold in local shops from about PLN 18.

Illustration of Feather reed grass 'Karl Foerster' — An illustration of the typical shape of the mature plant, not a photo.

What it's good for, and what it isn't

A strictly upright, narrow ornamental grass that flowers as early as the start of summer and keeps its straw-coloured stems standing all winter. It works as a vertical accent even in tight spaces or in a row as a seasonal screen, and copes well with heavy clay. It is sterile, so it does not seed around; give it sun because it flops in shade, and cut it back in late winter before new growth starts.

Watch out for

It has no serious pests or diseases. Rust can appear on the leaves after long rainy spells. It is a cool-season grass, so in the hot, dry summers of Central Europe growth pauses and the foliage can brown in soil that dries out without watering; there it appreciates some afternoon shade and soil that stays moist. In shade it flowers less and flops.

Key facts

Light: Full sun, Part shade
Water need: Medium
Care: Low
Size after 10 years: 1.5 m × 75 cm
Hardiness: down to -29 °C
Foliage: Deciduous
Flowering: J F M A M J J A S O N D June–August, pink, purple

All details

Group	Ornamental grass
Light	Full sun, Part shade
Size after 10 years	1.5 m × 75 cm
Ultimate size	0.9–1.5 m × 45–75 cm
Hardiness	down to -29 °C (USDA 4, RHS H7)
Soil	Average garden soil, Clay, Sandy, Calcareous, Acidic
Foliage	Deciduous
Flowering	June–August, pink, purple
Water need	Medium
Drought tolerance	Medium
Maintenance	Low
Root aggressiveness	Low
Suckering	no
Spreading	Low
Distance from buildings	no data
Distance from paving	no data
Litter	not typical
Planting distance	60 cm
For dogs	Non-toxic (uncertain)
For cats	Non-toxic (uncertain)
For children	no data
Typical price	from about PLN 18

Toxicity data is for information only. If your pet or child has eaten a plant, contact a vet or a doctor.

Sizes and prices available

The same plant is sold as a small pot and as a specimen several metres tall, and the price follows. Prices are rounded and for guidance only.

Size	Typical price
size not stated	approx. PLN 18

Frequently asked questions

Data updated: October 17, 2026 · How our data is made

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