Photo: no rights reservedCC0 1.0via iNaturalist
Sourgrass Plant Care
Digitaria insularis (L.) Mez ex Ekman
Updated · Sources · How we source care data
This plant's most distinctive feature is its slender, spiky leaves that form dense clumps. Originating from Africa, Digitaria insularis, commonly known as crabgrass, is highly sought after by plant collectors for its ability to thrive in hot, dry conditions and its unique texture that adds visual interest to any garden.
Every 7–14 days
Full sun to partial shade
65–85°F
40–70%
At a glance
How do you care for Sourgrass?
Water Sourgrass every 7–14 days, letting the top layer of soil dry out between waterings, and give it full sun to partial shade. It prefers temperatures of 65–85°F (18–29°C) and 40–70% humidity. Fertilize it every 8 months during the growing season.
Where Is the Sourgrass Native To?
What Is the Sourgrass?
Sourgrass (Digitaria insularis) belongs to the Poaceae family within the Digitaria genus. Sourgrass is native to Central and South America and the southern parts of the United States and has been introduced into other parts of the world.
Sourgrass displays an upright, spreading grass growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Sourgrass produces small inconspicuous flowers on tall spikes.
Leaf size: approximately 12 inches.
How Often Should You Water a Sourgrass?
Digitaria insularis requires watering every 7–14 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–14 days
Let soil partially dry between waterings
What Light Does the Sourgrass Need?
Sourgrass thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Sourgrass Prefer?
Digitaria insularis grows best at temperatures of 65–85°F. Sourgrass prefers humidity levels of 40–70%.
Temperature
65–85°F
Humidity
40–70%
What Soil Mix Works Best for a Sourgrass?
Well-draining sandy loam with good fertility. Good drainage is essential for Sourgrass to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Sourgrass?
Feed Sourgrass every 8 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every 8 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a Sourgrass?
Divide and repot every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Sourgrass?
Sourgrass can be propagated through seeds, division of clumps. Similar propagation techniques also apply to digitaria californica plant care, which shares the same genus.
Is the Sourgrass Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Sourgrass, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the Sourgrass?
Sourgrass is susceptible to aphids, grasshoppers, armyworms. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
What USDA Hardiness Zone Does the Sourgrass Need?
Sourgrass grows outdoors in USDA Zone 9b – 12b. It survives winters down to planting zone 9b. Sourgrass is native to Central and South America and the southern parts of the United States and has been introduced into other parts of the world. In cooler regions, grow Sourgrass as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 9b – 12b
Keep exploring plants
Sourgrass is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Digitaria genus — compare its care with other Digitaria species on PlantoScan.
Digitaria is part of the Poaceae plant family — browse all Poaceae genera and species.
Sourgrass thrives in bright light and direct sun — see other bright-light plants.
More Digitaria Species
Other Digitaria species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Digitaria insularis (L.) Mez ex Ekman, family Poaceae (first published in Ark. Bot. 11(4): 17 (1912)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Sourgrass, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Photo: Public domain, CC0 1.0, iNaturalist — original.
- Hardiness zone: USDA Zone 9b – 12b, estimated from the plant's typical growing conditions.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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