Fertilising guide
How to fertilise Spotted Sinningia (Sinningia guttata)— schedule & NPK
Also called Spotted Sinningia, Spotted Gloxinia.
More about spotted sinningia
About Spotted Sinningia
Sinningia guttata · also called Spotted Sinningia, Spotted Gloxinia · flowering
Sinningia guttata is a tuberous gesneriad native to the Atlantic Forest of Brazil, producing upright stems to about 40 cm topped with white, maroon-spotted tubular flowers. It grows from a caudex tuber and enters dormancy after flowering, at which point watering should be reduced significantly until new growth resumes. Provide bright, indirect light and avoid splashing water on leaves to prevent spotting. The ASPCA lists the Sinningia genus (Gloxinia) as non-toxic to cats and dogs; individual species not separately verified should be treated as mildly toxic until confirmed.
Growth habit: Upright herbaceous perennial growing from a surface or partially buried caudex tuber, dying back to the tuber during dormancy.
Watch for — Leaf spot from water splash: Water droplets on leaves cause brown or pale spots; always water at soil level and keep foliage dry to prevent fungal and physiological spotting.
What fertiliser spotted sinningia actually wants — and why
Spotted Sinningia is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.
A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root formula.
For the language behind the three numbers on the bottle — what nitrogen, phosphorus and potassium each do — see the NPK ratio explained entry. The short version for spotted sinningia: match the feed to the job the plant is doing right now, not to a generic “plant food” on the shelf.
How often to feed spotted sinningia, and which months
Feeding only earns its keep while the plant is in active growth and can use the nutrients — pour feed into a dormant or low-light plant and it simply builds up as root-burning salt. For spotted sinningia:
Apply a balanced liquid fertiliser at half strength every two weeks during active growth; stop feeding once the plant begins to go dormant. Treat that as sparingly through the growing season between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.
The dormant-season rule matters more than the exact interval: skip feeding entirely when spotted sinningia is resting. For the wider context on indoor feeding rhythms across the seasons, the houseplant fertiliser schedule walks through the year month by month.
What strength to mix for spotted sinningia
Half strength is the safe default for spotted sinningia — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
Feeding always goes onto already-damp soil, never dry roots — water spotted sinningia first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the spotted sinningia watering schedule.
Signs you are over-feeding spotted sinningia
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for spotted sinningia:
- Brown, crispy leaf tips and edges with no sign of underwatering.
- A white, crusty salt deposit on the soil surface or pot rim.
- Weak, pale, stretched new growth that flops.
- Lower leaves yellow and drop while the soil is correctly watered.
Signs you are under-feeding spotted sinningia
- Uniformly pale or yellow-green leaves, oldest first.
- Noticeably small new leaves and stalled growth in good light and season.
- A generally tired, lacklustre look despite correct watering and light.
If the symptoms point at watering, light or roots rather than nutrition, the full spotted sinningia care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Flush the pot of spotted sinningia with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.
Organic vs synthetic feeds for spotted sinningia
Organic options
A diluted seaweed or worm-casting feed, or fish emulsion if you can tolerate the smell indoors. UK: Westland or Baby Bio Organic, dilute seaweed; US: Espoma Indoor! or Neptune's Harvest fish & seaweed. Slow, gentle and hard to overdo.
Synthetic / liquid feeds
A general-purpose houseplant liquid at half strength — UK: Baby Bio, Westland Houseplant Feed or Phostrogen; US: Miracle-Gro Indoor Plant Food or Schultz. Convenient and fast-acting; the only risk is overdoing it.
Brand names are examples, not endorsements, and UK and US ranges differ — check the label’s own NPK and dilution rate, since formulations change.
Fertilising spotted sinningia — frequently asked questions
What fertiliser does spotted sinningia need?
A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root formula. Spotted Sinningia is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.
How often should I feed spotted sinningia?
Apply a balanced liquid fertiliser at half strength every two weeks during active growth; stop feeding once the plant begins to go dormant. Apply a balanced liquid fertiliser at half strength every two weeks during active growth; stop feeding once the plant begins to go dormant. Treat that as sparingly through the growing season between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.
What strength of feed for spotted sinningia?
Half strength is the safe default for spotted sinningia — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
What does over-feeding spotted sinningia look like?
Brown, crispy leaf tips and edges with no sign of underwatering. A white, crusty salt deposit on the soil surface or pot rim. Weak, pale, stretched new growth that flops. Lower leaves yellow and drop while the soil is correctly watered. Feeding spotted sinningia year-round on a fixed schedule, including dark winter months, is the most common mistake — it cannot use the nutrients in low light and the surplus simply burns the roots and crusts the soil.
Should I flush the soil of spotted sinningia?
Flush the pot of spotted sinningia with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.
Keep reading
- Spotted Sinningia care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water spotted sinningia — the watering schedule
- The houseplant fertiliser schedule — feeding through the year
- NPK ratio explained — what the three numbers on the bottle mean
- How to fertilise variegated greater periwinkle
- How to fertilise japanese spurge
- How to fertilise green sheen japanese spurge
- All 10153 fertilising guides in the Growli library