Rose Grass (Red Star) care

Light

Rose Grass needs sun on the leaves, not just bright ambient room light. Requires full sun — at least 6 hours of direct sunlight daily — to flower well. In hot climates, light afternoon shade prevents petal scorch, but deep shade suppresses blooming entirely. A south or west-facing windowsill in the northern hemisphere is the default; anywhere else, expect the plant to stretch and pale out within a season.

Watering

Water rose grass moderate during growth; almost dry in winter dormancy. The actual day count varies with pot size, light, and season — the finger test (or lifting the pot to feel its weight) is more reliable than a fixed calendar. Empty any drainage saucer afterwards so the pot isn't sitting in water. Water freely from spring through summer while in active growth, allowing the top inch of soil to dry between waterings. Crucially, reduce to near-zero water from autumn through late winter; wet winter corms rot rapidly.

Soil and pot

Rose Grass grows best in gritty, sharply draining alpine or loam-based mix. A 50:50 blend of John Innes No. 2 (or loam) and horticultural grit or perlite works well. Good drainage is non-negotiable — standing moisture in winter is fatal. In containers, raise the pot on feet to ensure free drainage. A pot with a working drainage hole is non-negotiable for this species — even free-draining mix will turn soggy in a closed planter. If you love the look of a decorative pot without a hole, use it as a cachepot around an inner nursery pot you can lift out to water.

Humidity and temperature

Rose Grass sits happiest at around Low to moderate, 30–50% humidity and 5–25°C (41–77°F). Tolerates low ambient humidity without issue, reflecting its montane South African origins. Avoid high humidity combined with wet soil in winter, which accelerates corm rot. If you keep the room above 5–25°C year-round and avoid placing the plant near a cold draught, a hot radiator, or an air-conditioning vent, you have already handled the two biggest indoor stressors.

Fertilising

Feed rose grass sparingly. Apply a balanced, low-nitrogen liquid fertiliser (e.g., 10-10-10) at half strength every 3–4 weeks during the growing season (spring–summer). Stop feeding once flowering ends and the plant begins to die back for dormancy. Skip fertiliser entirely on a stressed, recently-repotted, or actively wilting plant — fertiliser salts make damage worse, not better. Wait for a round of healthy new growth before resuming a feeding rhythm.

Common problems

Below are the issues we see most often on rose grass in the Growli community. Each is annotated with the most common cause so you know where to start.

• Corm rot in winter — The most common cause of plant loss. Wet soil during dormancy causes rapid rot of the corms. Ensure near-dry conditions from autumn through late winter and use perfectly draining gritty compost.
• Failure to flower — Usually caused by insufficient sunlight or skipping the dry winter rest period. Without full sun and a distinct dormancy, the corms do not set flower buds. Move to the sunniest available spot and enforce winter dryness.
• Vine weevil larvae — Vine weevil grubs can destroy corms when plants are grown in containers. Apply a biological control (Steinernema kraussei nematodes) in late summer or treat with a systemic imidacloprid drench as a preventive measure.

Propagation

Divide congested clumps in early autumn after foliage dies back, separating individual corms and replanting immediately at shallow depth (1–2 cm). Seed can be sown fresh in gritty compost at 15–18°C; germination takes 4–6 weeks but plants take 2–3 years to flower. Propagation is the cheapest, most satisfying way to expand a collection — and it doubles as insurance against losing a mature plant to an accident. Take a backup cutting once the parent is established and healthy.

Toxicity to pets

Rose Grass is pet-safe. Rhodohypoxis baurii is not individually listed by ASPCA. It belongs to the family Hypoxidaceae, which has no widely reported toxic principle in the veterinary literature. However, because it is a small corm-forming plant not commonly assessed, caution is always appropriate — monitor pets for unusual reactions. If you keep cats, dogs, or curious children in the house, weigh placement carefully — a high shelf or a hanging planter is enough for casual safety. For severe ingestion incidents, call your local vet and the ASPCA Animal Poison Control Center (in the US, 888-426-4435).

Pet-safety status is sourced from the ASPCA Toxic and Non-Toxic Plant List, which catalogues the most-asked-about plants for cats, dogs, and horses.

Rose Grass deep-dive guides

Every aspect of rose grass care, each with its own calibrated guide:

• Common rose grass problems & fixes
• Rose Grass watering schedule
• Rose Grass light requirements
• Best soil mix for rose grass
• Rose Grass fertilizing guide
• When to repot rose grass
• How to propagate rose grass
• How to prune rose grass
• What's eating my rose grass?
• Rose Grass growth rate & size
• Rose Grass cold hardiness
• Rose Grass temperature & humidity
• Is rose grass toxic to cats & dogs?
• Is rose grass toxic to cats?
• Is rose grass toxic to dogs?
• Getting rose grass to bloom

Featured in these plant shortlists

Rose Grass qualifies for 10 curated Growli shortlists — each one filtered objectively from our structured plant-care library, so the selection is consistent and checkable:

• Best pet-safe houseplants — Houseplants the ASPCA lists as non-toxic to cats and dogs — every one verified against the ASPCA toxic and non-toxic plant list.
• Best flowering houseplants — Indoor plants grown for their blooms — selected from the flowering species in Growli’s plant-care library.
• Best pet-safe flowering plants — Flowering houseplants the ASPCA lists as non-toxic to cats and dogs — colour and blooms in a pet home, without the worry.
• Best pet-safe plants for bright light — Non-toxic to cats and dogs and happy in a bright, sunny spot — safe plants for your best-lit windowsill.
• Best small & tabletop houseplants — Compact houseplants that stay under about 40 cm — desk, shelf and windowsill plants that never outgrow a small space.
• Best houseplants for full sun — Houseplants that want direct sun — the species for a hot south or west-facing windowsill where shade-lovers scorch.
• Best houseplants for a cool room — Houseplants that tolerate cool conditions down to about 10°C — for an unheated spare room, hallway, porch or a home kept cool.
• Best cat-safe plants — Houseplants the ASPCA lists as non-toxic to cats (and dogs) — safe greenery for a home with a curious cat.
• Best dog-safe plants — Houseplants the ASPCA lists as non-toxic to dogs (and cats) — safe greenery for a home with a curious dog.
• Best small pet-safe plants — Compact, tabletop houseplants that are also ASPCA non-toxic to cats and dogs — safe greenery for a desk or shelf.
• Browse all 29 plant shortlists — pet-safe, low-light, drought-tolerant and more

Related guides

Rose Grass is also commonly called Rose Grass or Red Star.

• Variegated Purple Moor Grass care — light, water and common problems
• Tall Moor Grass care — light, water and common problems
• Skyracer Moor Grass care — light, water and common problems
• All 8452 plant care guides in the Growli library