Empress of India Nasturtium (Garden Nasturtium) care

Light

Empress of India Nasturtium needs sun on the leaves, not just bright ambient room light. Full sun of 6+ hours produces the deepest leaf colour and the most prolific flowering. Partial shade is tolerated but diminishes both bloom intensity and foliage colour. 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 empress of india nasturtium when the top 3–5 cm of soil is dry, roughly every 7–10 days. 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. Drought-tolerant once established. Consistent overwatering creates lush foliage with scarce flowers. Allow soil to partially dry between waterings.

Soil and pot

Empress of India Nasturtium grows best in poor to average, well-draining loam or sandy soil. Rich, fertile soil strongly favours leaf production over flowers. Best in lean, well-drained beds. pH tolerance: 6.0–7.5. 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

Empress of India Nasturtium sits happiest at around 30–65% humidity and 10–24°C (50–75°F). Adaptable to typical garden humidity. Good airflow around plants reduces aphid infestations and late-season fungal issues. If you keep the room above 10–24°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 empress of india nasturtium sparingly. No supplementary feeding recommended in average soil. In very sandy, impoverished soil, a single dilute balanced feed at sowing is acceptable. Avoid high-nitrogen products. 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 empress of india nasturtium in the Growli community. Each is annotated with the most common cause so you know where to start.

• Aphids (blackfly and greenfly) — A classic aphid host; knock off with a water jet or apply insecticidal soap promptly to avoid heavy infestations.
• Large White caterpillars — Can strip foliage; hand-pick eggs and larvae or apply Bt spray.
• Powdery mildew — Late-season issue in humid weather; remove affected foliage and improve spacing.
• All foliage, few flowers — Almost always caused by rich soil or over-fertilising; transplant to a leaner bed.
• Slugs and snails — Damage young seedlings; protect with physical barriers or iron phosphate-based slug control.

Companion plants

Empress of India Nasturtium pairs well with Brassica oleracea, Cucumis sativus, Lycopersicon esculentum, and Allium schoenoprasum. These are species with similar light and water needs, so you can group them in the same room or on the same shelf and water as a batch.

Propagation

Sow seeds directly outdoors after the last frost date, 12 mm deep, 20–25 cm apart. Soak seeds for 12 hours before sowing to soften the hard seed coat. Germinates in 7–14 days at 15–21°C. 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

Empress of India Nasturtium is mildly toxic to pets. The ASPCA lists Tropaeolum majus as toxic to dogs and cats, with ingestion potentially causing gastrointestinal irritation. While the flowers and foliage are edible and peppery for humans, pets should be discouraged from eating this plant. 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.

Empress of India Nasturtium deep-dive guides

Every aspect of empress of india nasturtium care, each with its own calibrated guide:

• Common empress of india nasturtium problems & fixes
• Empress of India Nasturtium watering schedule
• Empress of India Nasturtium light requirements
• Best soil mix for empress of india nasturtium
• Empress of India Nasturtium fertilizing guide
• When to repot empress of india nasturtium
• How to propagate empress of india nasturtium
• How to prune empress of india nasturtium
• What's eating my empress of india nasturtium?
• Empress of India Nasturtium growth rate & size
• Empress of India Nasturtium cold hardiness
• Empress of India Nasturtium temperature & humidity
• Is empress of india nasturtium toxic to cats & dogs?
• Is empress of india nasturtium toxic to cats?
• Is empress of india nasturtium toxic to dogs?
• All 10 Tropaeolum varieties
• Getting empress of india nasturtium to bloom

Featured in these plant shortlists

Empress of India Nasturtium qualifies for 5 curated Growli shortlists — each one filtered objectively from our structured plant-care library, so the selection is consistent and checkable:

• Best drought-tolerant houseplants — Houseplants that prefer to dry out — forgiving of forgotten watering and ideal for travel or busy weeks.
• Best flowering houseplants — Indoor plants grown for their blooms — selected from the flowering species in Growli’s plant-care library.
• 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.
• Browse all 30 plant shortlists — pet-safe, low-light, drought-tolerant and more

Related guides

Empress of India Nasturtium is also known as Empress of India Nasturtium, Garden Nasturtium, and Scarlet Nasturtium.

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