How to Care For Purple Fountain Grass

Last Updated on October 20, 2022 by Plant Mom Care

Purple fountain grass, indigenous to Africa and Asia, is fittingly named for its arcing spikes of purple flowers that grow gracefully from the mass of slender, long, burgundy-colored leaves. It is a fast grower and, while it can be planted in almost any season, it is best planted in spring. 

The seed heads appearing in autumn are attractive and add nice color to autumn flower gardens. Feathery seed plumes are often cut and used in dried flower arrangements.

It makes a nice focal point in mixed beds and container gardens.

Massing several plants together creates a beautiful privacy screen or border however, it may have to be staked to support it and grows best when planted in a location sheltered from strong winds.

When the plants are mature, they can reach around 5 feet tall and as wide and should be given lots of room in your garden, spaced out at least 3 feet between other plants, and planted in a deep and wide hole to accommodate the roots.

Purple Fountain Grass Light Requirements

This grass can tolerate some shade but prefers full sunlight for 6 – 8 hours every day although it’s generally grown outdoors, it can also do well indoors in cool conditions with lots of light. 

Purple Fountain Grass Watering

While it is thought to be drought-tolerant, it still needs consistent water while it’s getting established. Water new plants 1 or 2 times a week, allowing the soil to dry between watering. 

Outdoors, in gardens that occasionally receive rain, you don’t have to water the grass once it is established, if it is potted or if it grows outdoors in dry or hot areas, it might need watering occasionally.

Purple Fountain Grass Humidity

It has no specific humidity requirements.

Purple Fountain Grass Temperature

This grass is versatile regarding temperature conditions. It loves heat and will continue growing into autumn when daytime temperatures remain above 70°F. It’s cold hardy to 20°F, so if the temperature in your location remains around that, you can grow it as a perennial and prune it down in early spring every year. 

New growth emerges as the temperatures start climbing. In colder areas, the plant will thrive in spring, summer, and autumn and die back in winter — unless it is growing in pots and can be taken indoors for winter.

Purple Fountain Grass Soil

Fortunately, this grass isn’t very picky about soil – loamy soil can provide the best results, but it can grow well in other types of mixes, just as long as they drain well.

Purple Fountain Grass Repotting

It will outgrow the pot it is in sooner or later, particularly if it grows without repotting for some time. It’s easy to tell when it is time to repot the plant. 

If you lift the pot and see roots emerging from the drainage holes, then it has to be repotted but if roots appear on the topsoil, then they must be repotted soon. 

When the roots are more than soil in the pot, then it becomes an urgent matter, and the plant needs immediate repotting. It doesn’t like being root-bound as this can adversely affect the plant’s health.

Purple Fountain Grass Propagation

This plant is propagated by division or seeds. It will easily self-seed outdoors, but root division is more reliable and faster to propagate than germinating seeds. The ideal season to divide the plant in autumn when flowering has stopped, just as the plant is becoming dormant.

Dig the plant up and use a sharp tool to split it into two or more portions that have healthy leaves and roots. Remove any dead or rotten foliage and roots. Replant straight away and keep the soil moistened while the new division settles down and gets established in its new home.

It’s easy to propagate the plant from seed although it takes some time to see the results. Harvest seeds from flowering stems after they dry, usually in autumn. 

Cut away a healthy stem and let the flower stalk become dry in a cool spot. Collect the seeds and surface them in potting soil with a light dusting of sand on top. Water until the soil is moistened evenly. Place the pot inside a plastic bag Cut a few small slits in the bag so the seeds can breathe. Once the seedlings germinate and have 2 sets of true leaves, transfer them into larger pots. Harden the plants outdoors in spring and transplant them into prepared pots or garden beds.

Additional Care

This plant grows well enough in poor soil, but fertilizing it will boost growth and provide additional nutrients it requires when flowering. It typically flowers in summer and feeds it every month with a balanced, slow-release fertilizer following the directions on the label.

The normal method to prune this plant is to severely prune it down in late winter or spring before new growth starts. This will remove dead growth and improve sun exposure and air circulation to encourage healthy new growth. To prune down the plant in spring, bunch the leaves together and bind them with a rope or masking tape. Cut the leaves away straight across the stems, about 4 to 6 inches from the plant’s base. Remove any plant debris from the soil.

To overwinter the plant, if it is growing in your garden, dig up the plant and keep it in any sort of container and move it inside in winter to survive extreme cold. Cut the stalks down to around 3 inches from the soil. 

Keep the container in an area under moderate light where the temperature will not drop to freezing levels as the roots won’t endure freezing temperatures. Keep the soil lightly watered but not soggy, and never let it dry out. Once the weather turns warmer in the spring, acclimatize the plant by taking it outdoors during the day and back indoors at night. Replant it in the garden when the weather warms up and will grow back normally.

Purple Fountain Grass Common Problems

This rugged grass is very resistant to pests and diseases but here are some issues to look for when growing this outdoors in your garden.

Slugs and snails might lurk around the plant and occasionally chomp on it. Don’t worry as they won’t cause serious and long-term damage.

Because of moisture or trapped humidity in the spaces between dense clusters, rust fungus can be a frequent occurrence. Make sure you provide enough space between plants (3 feet apart) to improve air circulation.