Stromanthe

( stroh - MAN - thee )

At-A-Glance Information

This genus of plants includes species of tropical flowering herbaceous plants native to the Americas. They appreciate full shade to filtered sun and need regular water to perform well in the landscape. They form upright, bushy clumps of foliage from underground rhizomes, and produce elongated leaves. Use these plants in the garden as vibrant shade accents, to add color to mixed beds and borders, or as a container plant on a patio or walkway. They are commonly included in shade, woodland, tropical, and informal gardens.

Stromanthe Species and Varietals

The genus Stromanthe includes 35 species, and is a member of the plant family Marantaceae. The plants in this genus are related to those in Maranta (Prayer Plant), Calathea (Prayer Plant) and Goeppertia (Prayer Plant). Stromanthe plants are suited for USDA hardiness zones 10 through 12, and are grown as indoor or greenhouse plants elsewhere. To find your zone, click here: Zone Map.

Stromanthe sanguinea (Stromanthe, Triostar Stromanthe, Caetê-Bravo, Maranta-Sanguínea, Maranta-Tricolor, Maranta-Triostar)
These plants are native to the Brazilian rainforest, and produces leaves with green upper surfaces and red to purplish undersides. Plants reach up to 5 feet tall in the ground. Flowers are small and white, surrounded by cherry-red to orange bracts. This species is commonly kept as an ornamental houseplant, and the main (and very popular) cultivar 'Tricolor' has leaves marked with white and pink.

Caring for Stromanthe

Stromanthe can be grown outdoors in climates that remain between 65 and 80 degrees Fahrenheit year-round. They prefer a space with bright, indirect light that is protected from direct sun, as foliage tends to burn. Foliage can also be damaged by wind. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 5.5 and 7.0 (slightly acidic to neutral). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water regularly, keeping the soil moist but ensuring it does not become waterlogged. As a general rule of thumb, water whenever the top inch of soil feels dry to the touch.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. Pruning is simple; remove any damaged, diseased, or dead foliage at any time during the growing season, and remove spent flower spikes to neaten up the appearance of plants and encourage reblooms. Stromanthe plants can survive in the landscape for between 5 and 10 years if given proper care before needing to be replaced.

Growing Stromanthe Indoors
Stromanthe grown indoors will need to be placed in an area that receives indirect light. In their native landscapes, they grow in the understory of thick forested sites, and never receive direct sunlight, which can scorch the leaves. The best light is indirect sun from an east-, south-, or west-facing window. Choose a container that has a drainage tray underneath that can be filled with rocks; this will help to keep the area around the plant humid. The container should be 1-2 inches wider and deeper than the nursery pot or root ball. Fill with a well-draining substrate; a great mix for Stromanthe is a mixture of 2 parts peat moss, 1 part standard soil, 1 part perlite, and 1/2 part horticultural charcoal. Water regularly as the plant establishes itself in its new pot. At maturity, these plants appreciate consistently moist soil; as a general rule of thumb, water whenever the top inch of soil feels dry to the touch. After a few years, these plants will need to be divided to ensure ongoing health. For instructions on how to successfully divide a Stromanthe plant, see the Propagation section below.

Propagation

The best way to propagate a Stromanthe is to divide already existing plants. For instructions on how to divide these tropical plants, see the directions below:

Propagating Stromanthe by Division
Division is the easiest way to propagate these plants. The idea behind this method is that you are taking an existing clump of live plants and breaking it into smaller segments. This is something you will want to do whether or not you are looking to propagate your plant, as they need to be divided every three to five years to keep them healthy. Otherwise, the roots will become too crowded, especially if they are being grown in a cramped border or container. To use this method, gather a clean shovel, clean pruning saw, extra pots if you are not going to immediately replant your divisions in the ground, and well-draining soil to fill the pots.

Identify the area of plants you're going to divide. Start by loosening the soil around the plant with your shovel, working your way inward to avoid causing damage to the rhizomes. If the Stromanthe is being grown in a container, remove the entire root ball from the pot. Once you've gotten it out of the ground or pot, lay it out on its side.
Divide the clump into segments, either with your shovel or with a pruning saw, as many as you'd like as long as there are at least a few growing points per rhizome piece. Inspect each segment to ensure healthy roots and lay them out on the ground. If there are any blackened or rotted out root areas, trim them at this time.
If you will be planting your Stromanthe in the ground, this is when you'll prepare your new hole. Dig a hole (large enough to accommodate the root ball of the clump you are planting) in the ground with your shovel in a sunny location with soil that is well-draining. If you have issues with drainage in your garden, amend with loamy soil before planting. Backfill and water generously. If planting in a container, simply add well-draining substrate and top with a layer of mulch.