# Purple fountain grass (Pennisetum setaceum 'Rubrum')

Canonical: https://plantguide.ae/plants/fountain-grass · Updated: 2026-10-05
Source: Ghaf Gardens (https://plantguide.ae/plants/fountain-grass)

Purple fountain grass · also called Red fountain grass, Burgundy fountain grass, Pennisetum rubrum  
ornamental-grass · adapted · family Poaceae · grows 0.6–1.3 m tall, 0.5–0.9 m wide · fast growth  
full sun · low water need  
Ratings for Dubai (1–5, 5 is best): heat 4 · salt 3 · drought 4 · shade 2 · ease of care 4  
Sow or plant: Oct–Mar  
Uses: specimen, container  
Garden styles: desert-modern, manicured, luxury

> **Advisory (caution):** The green species, Pennisetum setaceum (now Cenchrus setaceus), is invasive in Hawaii, Australia, South Africa, southern Europe and southern California, and the EU has banned its import, sale and planting since 2017. The burgundy 'Rubrum' is sterile and not considered invasive, but UAE nurseries sell both forms. Buy 'Rubrum' by name, remove plumes before they shatter, and keep it out of wadis, verges and open desert.

Purple fountain grass gives Dubai beds their burgundy plumes and arching movement. The 'Rubrum' form rarely sets seed, but its green parent species is invasive on several continents.

## About

Meet purple fountain grass, the plant that shows what movement can do for a bed. Its blades are not green but a deep burgundy, and they fall in a loose arc from the crown so that the whole clump reads as a fountain caught mid-fall. Add the bristled plumes of the warm months and a single plant looks as if it is breathing.

The technicality behind the look is a C4 bunch grass: a plant that photosynthesises efficiently in heat and strong light, which is why it keeps growing through weather that stalls cool-season grasses. Its leaves are narrow and its crown is compact, so each clump holds its shape without staking or clipping.

What it brings to a garden is mood rather than mass: a warm-toned softness against stone, glass and gravel. Its one real caveat is the family it belongs to. Choose the sterile burgundy 'Rubrum', manage the plumes, and it is a good neighbour.

Purple fountain grass is among the most widely planted ornamental grasses in the UAE, and the reason is visible from across a garden: arching burgundy blades in a fountain-shaped clump about a metre tall, topped through the warm months with soft, bristled plumes in a deeper purple. 'Rubrum' is a red-leaved cultivar of Pennisetum setaceum, a grass of the open, scrubby country of East Africa, the Middle East and south-western Asia, which many botanists now file under Cenchrus setaceus. That dry-country origin explains why it suits Dubai: full sun, free drainage and very little water once established.

It has to be discussed honestly, because the species is a proven invader outside its home range. The green-leaved Pennisetum setaceum is a serious weed in Hawaii, Australia, South Africa, southern Europe and southern California, where it displaces native plants and raises fire risk; Florida lists it as a Category 2 invasive and the EU prohibits its import, sale and planting. The burgundy 'Rubrum' is the garden answer: Cal-IPC describes it as sterile and not considered invasive, and Missouri Botanical Garden notes it rarely sets seed. The sensible rule is to plant 'Rubrum' by name, deadhead the plumes before they shatter, pull any green seedling that appears and keep it away from wadis and open desert edges.

In the garden it behaves like a short, soft fountain that catches low sun. Plant it in groups of five or seven rather than singly, set against the hard edges of limestone, gravel or [Agave](https://plantguide.ae/plants/agave.md), and let it sway beside the silver foliage of [Texas Sage](https://plantguide.ae/plants/texas-sage.md). If you want the same fine, arching texture from a species that belongs here, [Desert grass](https://plantguide.ae/plants/desert-grass.md) is the native counterpart, quieter in colour and slower to bulk up. Wear gloves when cutting it back: UF/IFAS records skin irritation from handling the foliage.

## Through the year

Plant in the cooler months, October to March, so the roots settle before summer. New burgundy growth pushes after the late-winter cut-back in February, and plumes follow through the warm months, building to a soft haze above the clump. In peak summer it keeps growing if it is irrigated, though the clump can look thinner in the worst heat. In the cooler weeks growth slows and the plumes fade to buff. A hard cut to about 15 cm before spring growth resets the whole plant and keeps the burgundy fresh.

| When | What | Note |
| --- | --- | --- |
| Oct–Mar | Plant: Best planting window | Cooler months give the roots time to settle before summer. |
| Mar–Apr | New growth: Fresh burgundy growth after the cut-back |  |
| Mar–Nov | Flowers: Plume season | Plumes appear through the warm months and fade to buff as the weather cools. |
| Feb | Prune: Cut back hard | Cut to about 15 cm before new growth, and wear gloves. |
| Mar | Feed: Light spring feed | A slow-release feed is plenty; rich soil makes the clump floppy. |

## Care in Dubai

- **Watering in summer:** Drought tolerant once established, but a deep soak once or twice a week through summer keeps the clump full. Let the surface dry between waterings.
- **Watering in winter:** Reduce sharply; rain and an occasional drink are usually enough.
- **While establishing:** Water every few days for the first month or two, then taper as the roots establish.
- **Soil:** Free-draining sandy or gravelly soil. It tolerates poor and alkaline ground; avoid heavy, waterlogged clay.
- **Feeding:** A light slow-release feed in spring is enough. Rich soil and heavy nitrogen give lanky, floppy growth.
- **Pruning:** Cut the whole clump back to about 15 cm in late winter, before new growth starts, and remove plumes before they shatter. Wear gloves: UF/IFAS records skin irritation from handling the foliage.
- **Planting:** Plant October to March in full sun, 60 to 90 cm apart. Buy the burgundy 'Rubrum' by name, not unlabelled green fountain grass.
- **Pests and problems:** Generally trouble-free

## Good and bad

**Pros**
- Burgundy leaves and plumes add colour and movement that few Dubai grasses can match
- Drought tolerant and happy in full sun and sandy, alkaline soil once established
- Fast growing, so a nursery pot fills its space quickly
- Widely sold across the UAE, in small and large pots
- Needs little feeding and almost no pest attention

**Cons**
- The green parent species is invasive in Hawaii, Australia, South Africa and southern Europe
- Foliage can irritate skin, so gloves are needed when cutting back
- Grows dull and lax in shade; it wants full sun
- Needs a hard cut-back each late winter to stay tidy

## Common mistakes

- Buying unlabelled fountain grass. UAE nurseries sell both the green species and burgundy 'Rubrum'; the green one is the invasive form, so ask for the cultivar by name.
- Planting it beside a wadi, verge or open desert plot. Escapes happen at the edge of managed ground, so keep it in beds and pots.
- Leaving plumes to ripen and shatter. Even a rarely seeding cultivar is best deadheaded, and the green species certainly self-sows.
- Putting it in shade or heavy clay. It wants full sun and drainage; in shade the growth turns dull and lax.
- Skipping the late-winter cut-back, so old brown blades hide the fresh burgundy growth.

## Good to know

- The accepted botanical name is now Cenchrus setaceus, since Pennisetum was merged into Cenchrus, though nurseries and most garden books still say Pennisetum setaceum.
- Cal-IPC rates the species Moderate in California and notes that the red 'Rubrum' is sterile; the EU has prohibited import, cultivation, trade and planting of the species since 2017.
- It is native to open, scrubby habitats from East Africa through the Middle East and south-western Asia, which is why it copes with Gulf heat and poor soil.
- UF/IFAS lists it as a Category 2 invasive in Florida and records skin irritation from handling the foliage.

## Using it in a garden

Roles: Border accent, Mass planting in drifts, Gravel garden planting, Container

Give it full sun and free-draining soil, and plant it in odd-numbered groups of five or seven, 60 to 90 cm apart, so the clumps knit into a single moving drift. It reads best against hard, pale surfaces such as limestone, gravel or rendered walls, and beside silver or grey foliage that lets the burgundy glow. Keep it in managed beds and pots rather than at the edge of open ground, and deadhead the plumes before they shatter.

- [Agave](https://plantguide.ae/plants/agave.md): Agave's rigid, blue-grey rosettes give a hard counterpoint to the fountain grass's soft burgundy arcs, and both ask for full sun and little water.
- [Texas Sage](https://plantguide.ae/plants/texas-sage.md): Silver foliage and purple blooms on texas sage pick up the grass's colour while sharing its taste for free drainage and low irrigation.
- [Lantana](https://plantguide.ae/plants/lantana.md): Lantana's small, bright flower heads add warm colour at the grass's feet through the long, hot season.
- [Desert grass](https://plantguide.ae/plants/desert-grass.md): The native desert grass offers a similar fine texture and can be drifted among the fountain grass to bring a locally rooted look to the same bed.

## FAQ

**Is purple fountain grass invasive in Dubai?**  
The green species, Pennisetum setaceum, is a recognised invader in Hawaii, Australia, South Africa, southern Europe and California. The sources we reviewed do not record it escaping in the UAE, but the burgundy 'Rubrum' is the safer choice: Cal-IPC describes it as sterile and not considered invasive. Plant it by name, deadhead the plumes and keep it away from wadis and open desert.

**What is the difference between 'Rubrum' and ordinary fountain grass?**  
'Rubrum' has burgundy leaves and purple plumes and rarely sets seed. The ordinary species has green leaves and paler plumes and seeds freely, which is why it escapes in other countries. UAE nurseries sell both, so check the label.

**How much water does it need in a Dubai summer?**  
Little once established, but it looks fullest with a deep soak once or twice a week through the hottest months on free-draining soil. Let the surface dry between waterings rather than keeping it constantly damp.

**When should I cut it back?**  
In late winter, around February, before new growth starts. Cut the clump to about 15 cm and wear gloves, as UF/IFAS records skin irritation from the foliage.

**Is there a native grass with a similar look?**  
[Desert grass](https://plantguide.ae/plants/desert-grass.md) (Pennisetum divisum) is the UAE native counterpart, with fine, arching blue-green leaves and soft spring plumes. It is quieter in colour and slower to bulk up, but it belongs in the landscape and asks for even less water.

## Related plants

[Desert grass](https://plantguide.ae/plants/desert-grass.md) · [Texas Sage](https://plantguide.ae/plants/texas-sage.md) · [Agave](https://plantguide.ae/plants/agave.md) · [Lantana](https://plantguide.ae/plants/lantana.md)

## Photos

![Poaceae - Red Fountain Grass; Ornamental plant,beautiful hedge plant,leaves purple,feathery plumes.](https://upload.wikimedia.org/wikipedia/commons/7/7b/Pennisetum_setaceum_Rubrum-1-Semmozhi_Poonga-coimbatore-India.jpg)  
Photo: Yercaud-elango / CC BY 4.0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Pennisetum_setaceum_Rubrum-1-Semmozhi_Poonga-coimbatore-India.jpg))

![Pennisetum setaceum rubrum tomado en el campus universitario de la PUCP en el ecosistema 7: Jardín de Palmeras o Palm...](https://upload.wikimedia.org/wikipedia/commons/6/61/Pennisetum_setaceum_rubrum_en_la_PUCP.jpg)  
Photo: Noribeets2003 / CC0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Pennisetum_setaceum_rubrum_en_la_PUCP.jpg))

![Pennisetum setaceum 'Rubrum' conocida como Pasto fuente Púrpura, tomada en el campus PUCP.](https://upload.wikimedia.org/wikipedia/commons/3/30/Pennisetum_setaceum_%27Rubrum%27_en_la_PUCP.jpg)  
Photo: Aripics / CC0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Pennisetum_setaceum_%27Rubrum%27_en_la_PUCP.jpg))

![Purple Fountain Grass (Pennisetum advena 'Rubrum') 2](https://upload.wikimedia.org/wikipedia/commons/0/08/Purple_Fountain_Grass_%28Pennisetum_advena_%27Rubrum%27%29_2.jpg)  
Photo: Mokkie / CC BY-SA 3.0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Purple_Fountain_Grass_(Pennisetum_advena_%27Rubrum%27)_2.jpg))

## Sources

- [Cal-IPC: Pennisetum setaceum profile (rating, 'Rubrum' sterile)](https://www.cal-ipc.org/plants/profile/pennisetum-setaceum-profile/)
- [UF/IFAS Plant Directory: Pennisetum setaceum (Florida status, invaded range, skin irritation)](https://plant-directory.ifas.ufl.edu/plant-directory/pennisetum-setaceum)
- [Wikipedia: Cenchrus setaceus (native range, EU restriction, taxonomy)](https://en.wikipedia.org/wiki/Cenchrus_setaceus)
- [Missouri Botanical Garden Plant Finder: Pennisetum setaceum 'Rubrum'](https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c257)
- [Plantes.ae: UAE nursery listing for Pennisetum setaceum and Pennisetum rubrum](https://www.plantes.ae/collections/outdoor-plants-grasses)