Fertilising guide
How to fertilise Super King Ixora Red (Ixora casei 'Super King')— schedule & NPK
Also called Super King Ixora Red, Super King Ixora, Taiwanese Ixora.
More about super king ixora red
About Super King Ixora Red
Ixora casei 'Super King' · also called Super King Ixora Red, Super King Ixora · tropical
Super King Ixora Red is a large, vigorous tropical evergreen shrub bearing spectacular extra-large clusters of brilliant red flowers. It thrives in full sun, acidic well-drained soil, and high humidity—conditions it rewards with near year-round bloom. Non-toxic to pets. Ideal for tropical hedges, foundation plantings, and large containers.
Growth habit: Large, dense, rounded evergreen shrub
Watch for — Iron chlorosis from alkaline soil: Yellow leaves with dark green veins (interveinal chlorosis) indicate iron deficiency caused by alkaline soil locking out iron uptake. Lower soil pH to 5.5–6.0 with elemental sulfur or acidifying fertiliser, and apply a chelated iron foliar spray for rapid correction.
What fertiliser super king ixora red actually wants — and why
Super King Ixora Red is an acid-loving plant — it can only take up nutrients in acidic soil, so the feed itself matters less than using an ericaceous formula and never liming.
An ericaceous (acidic) fertiliser, formulated to keep the soil pH low and supply iron and trace elements in a form acid-loving roots can absorb. Ordinary feeds and any lime lock out iron and yellow the leaves.
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 super king ixora red: 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 super king ixora red, 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 super king ixora red:
Feed with an acid-formulated slow-release fertiliser (e.g., azalea/camellia blend) every 2–3 months during the growing season. Supplement with chelated iron micronutrient spray if interveinal chlorosis appears. Avoid high-phosphorus fertilisers, which can lock out iron and magnesium in acidic soils. In practice: an ericaceous feed in spring as growth resumes, repeated through the main growing months; never apply lime, bonemeal or wood ash, which raise pH.
The dormant-season rule matters more than the exact interval: skip feeding entirely when super king ixora red 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 super king ixora red
Follow the ericaceous product's own rate — these are formulated for the plant, so the dilution on the label is right for super king ixora red. The variable that actually matters is pH, not concentration.
Feeding always goes onto already-damp soil, never dry roots — water super king ixora red first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the super king ixora red watering schedule.
Signs you are over-feeding super king ixora red
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for super king ixora red:
- Brown, scorched leaf margins from too strong or too frequent a dose.
- White salt crust on the soil surface.
- Soft, lush growth that fruits or flowers poorly.
Signs you are under-feeding super king ixora red
- Yellowing leaves with green veins (iron chlorosis from high pH).
- Weak growth, poor cropping and an overall pale, stressed look.
- Stunted new shoots in spring despite adequate water and light.
If the symptoms point at watering, light or roots rather than nutrition, the full super king ixora red care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Flush super king ixora red with rainwater (not hard tap water, which raises pH) if salts build up; better still, mulch with pine needles or composted bark and water with rainwater to hold the acidity.
Organic vs synthetic feeds for super king ixora red
Organic options
Composted pine bark, pine-needle mulch, used coffee grounds and an organic ericaceous feed gently maintain acidity. UK: Vitax or Westland Ericaceous; US: Espoma Holly-tone or Dr. Earth Acid Lovers. Slow, soil-improving, hard to overdo.
Synthetic / liquid feeds
A liquid or granular ericaceous feed — UK: Miracle-Gro Ericaceous, Vitax or Westland; US: Miracle-Gro Acid-Loving Plant Food or Espoma Holly-tone. Pair with rainwater and an acidic mulch for it to work.
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 super king ixora red — frequently asked questions
What fertiliser does super king ixora red need?
An ericaceous (acidic) fertiliser, formulated to keep the soil pH low and supply iron and trace elements in a form acid-loving roots can absorb. Ordinary feeds and any lime lock out iron and yellow the leaves. Super King Ixora Red is an acid-loving plant — it can only take up nutrients in acidic soil, so the feed itself matters less than using an ericaceous formula and never liming.
How often should I feed super king ixora red?
Feed with an acid-formulated slow-release fertiliser (e.g., azalea/camellia blend) every 2–3 months during the growing season. Supplement with chelated iron micronutrient spray if interveinal chlorosis appears. Avoid high-phosphorus fertilisers, which can lock out iron and magnesium in acidic soils. Feed with an acid-formulated slow-release fertiliser (e.g., azalea/camellia blend) every 2–3 months during the growing season. Supplement with chelated iron micronutrient spray if interveinal chlorosis appears. Avoid high-phosphorus fertilisers, which can lock out iron and magnesium in acidic soils. In practice: an ericaceous feed in spring as growth resumes, repeated through the main growing months; never apply lime, bonemeal or wood ash, which raise pH.
What strength of feed for super king ixora red?
Follow the ericaceous product's own rate — these are formulated for the plant, so the dilution on the label is right for super king ixora red. The variable that actually matters is pH, not concentration.
What does over-feeding super king ixora red look like?
Brown, scorched leaf margins from too strong or too frequent a dose. White salt crust on the soil surface. Soft, lush growth that fruits or flowers poorly. Feeding super king ixora red an ordinary fertiliser, or growing it in hard tap water / limey soil, is the defining mistake — it triggers lime-induced chlorosis (yellow leaves, green veins) no amount of feeding fixes until the pH comes down.
Should I flush the soil of super king ixora red?
Flush super king ixora red with rainwater (not hard tap water, which raises pH) if salts build up; better still, mulch with pine needles or composted bark and water with rainwater to hold the acidity.
Keep reading
- Super King Ixora Red care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water super king ixora red — 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 xanthosoma albomarginatum
- How to fertilise xanthosoma atrovirens
- How to fertilise alocasia wollongong
- All 6887 fertilising guides in the Growli library