Fertilising guide
How to fertilise Calathea Medallion (Goeppertia roseopicta 'Medallion')— schedule & NPK
Also called Calathea Medallion, Rose-Painted Calathea, Medallion Prayer Plant, Calathea roseopicta 'Medallion'.
More about calathea medallion
About Calathea Medallion
Goeppertia roseopicta 'Medallion' · also called Calathea Medallion, Rose-Painted Calathea · houseplant
The Calathea Medallion is a striking prayer plant prized for round leaves with feathery green patterning and deep purple undersides that fold up at night. It needs bright indirect light, consistently moist soil, filtered water, and high humidity to avoid crispy edges. It is ASPCA non-toxic and safe around cats and dogs.
Growth habit: Clumping, evergreen rhizomatous perennial with an upright, bushy rosette of long-stemmed oval leaves. A "prayer plant" that raises and folds its leaves at night (nyctinasty) and lowers them by day. Slow to moderate grower.
Watch for — Crispy brown leaf edges: Usually low humidity, or fluoride/salts in tap water. Raise humidity above 60% and switch to filtered, distilled, or rainwater.
What fertiliser calathea medallion actually wants — and why
Calathea Medallion 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 calathea medallion: 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 calathea medallion, 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 calathea medallion:
Feed with a balanced houseplant fertiliser at half strength roughly monthly (or every two weeks if growing actively) during spring through early autumn. Do not fertilise in winter. Over-feeding causes salt build-up and brown tips, so flush the soil periodically. Treat that as monthly 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 calathea medallion 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 calathea medallion
Half strength is the safe default for calathea medallion — 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 calathea medallion first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the calathea medallion watering schedule.
Signs you are over-feeding calathea medallion
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for calathea medallion:
- 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 calathea medallion
- 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 calathea medallion care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Flush the pot of calathea medallion 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 calathea medallion
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 calathea medallion — frequently asked questions
What fertiliser does calathea medallion 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. Calathea Medallion 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 calathea medallion?
Feed with a balanced houseplant fertiliser at half strength roughly monthly (or every two weeks if growing actively) during spring through early autumn. Do not fertilise in winter. Over-feeding causes salt build-up and brown tips, so flush the soil periodically. Feed with a balanced houseplant fertiliser at half strength roughly monthly (or every two weeks if growing actively) during spring through early autumn. Do not fertilise in winter. Over-feeding causes salt build-up and brown tips, so flush the soil periodically. Treat that as monthly 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 calathea medallion?
Half strength is the safe default for calathea medallion — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
What does over-feeding calathea medallion 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 calathea medallion 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 calathea medallion?
Flush the pot of calathea medallion 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
- Calathea Medallion care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water calathea medallion — 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 snake plant
- How to fertilise dracaena
- How to fertilise peperomia
- All 389 fertilising guides in the Growli library