Growli
Let's go

Fertilising guide

How to fertilise Coral Bark Maple (Acer palmatum 'Sango-kaku')— schedule & NPK

Also called Coral Bark Japanese Maple, Sango Kaku Maple.

More about coral bark maple

About Coral Bark Maple

Acer palmatum 'Sango-kaku' · also called Coral Bark Japanese Maple, Sango Kaku Maple · flowering

Coral Bark Maple is a spectacular Japanese maple cultivar grown primarily for its vivid coral-red young stems, which glow in winter sunlight when leaves have fallen. Spring leaves emerge bright yellow-green, turning soft gold in autumn. A year-round ornamental for borders and containers. Not toxic to pets.

Growth habit: Upright, vase-shaped deciduous small tree

What fertiliser coral bark maple actually wants — and why

Coral Bark Maple 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 coral bark maple: 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 coral bark maple, 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 coral bark maple:

Apply a slow-release balanced granular fertiliser in early spring. A second light application in early summer supports vigorous growth. Avoid fertilising after late July — soft autumn growth is susceptible to frost damage and reduces stem colour intensity. 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 coral bark maple 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 coral bark maple

Half strength is the safe default for coral bark maple — 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 coral bark maple first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the coral bark maple watering schedule.

Signs you are over-feeding coral bark maple

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for coral bark maple:

Signs you are under-feeding coral bark maple

If the symptoms point at watering, light or roots rather than nutrition, the full coral bark maple care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

Flush the pot of coral bark maple 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 coral bark maple

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 coral bark maple — frequently asked questions

What fertiliser does coral bark maple 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. Coral Bark Maple 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 coral bark maple?

Apply a slow-release balanced granular fertiliser in early spring. A second light application in early summer supports vigorous growth. Avoid fertilising after late July — soft autumn growth is susceptible to frost damage and reduces stem colour intensity. Apply a slow-release balanced granular fertiliser in early spring. A second light application in early summer supports vigorous growth. Avoid fertilising after late July — soft autumn growth is susceptible to frost damage and reduces stem colour intensity. 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 coral bark maple?

Half strength is the safe default for coral bark maple — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.

What does over-feeding coral bark maple 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 coral bark maple 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 coral bark maple?

Flush the pot of coral bark maple 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