Fertilising guide
How to fertilise Hydrangea 'Incrediball' (Hydrangea arborescens 'Abetwo' (Incrediball))— schedule & NPK
Also called Incrediball hydrangea, strong annabelle hydrangea.
More about hydrangea 'incrediball'
About Hydrangea 'Incrediball'
Hydrangea arborescens 'Abetwo' (Incrediball) · also called Incrediball hydrangea, strong annabelle hydrangea · flowering
Incrediball is a smooth hydrangea bred as a sturdier 'Annabelle', producing huge rounded white flower heads on notably stronger stems that resist flopping. A tough, cold-hardy deciduous shrub, it blooms on new wood, so prune in late winter. The mophead blooms open lime-green, mature pure white, then fade to soft green.
Growth habit: Rounded, multi-stemmed deciduous shrub with thick, rigid stems engineered to support oversized globular flower heads without flopping; blooms on the current season's growth.
What fertiliser hydrangea 'incrediball' actually wants — and why
Hydrangea 'Incrediball' 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 hydrangea 'incrediball': 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 hydrangea 'incrediball', 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 hydrangea 'incrediball':
One feed of balanced slow-release fertiliser in early spring is sufficient. Excess nitrogen still produces weaker stems despite the cultivar's strength, so feed moderately. 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 hydrangea 'incrediball' 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 hydrangea 'incrediball'
Half strength is the safe default for hydrangea 'incrediball' — 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 hydrangea 'incrediball' first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the hydrangea 'incrediball' watering schedule.
Signs you are over-feeding hydrangea 'incrediball'
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for hydrangea 'incrediball':
- 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 hydrangea 'incrediball'
- 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 hydrangea 'incrediball' care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Flush the pot of hydrangea 'incrediball' 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 hydrangea 'incrediball'
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 hydrangea 'incrediball' — frequently asked questions
What fertiliser does hydrangea 'incrediball' 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. Hydrangea 'Incrediball' 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 hydrangea 'incrediball'?
One feed of balanced slow-release fertiliser in early spring is sufficient. Excess nitrogen still produces weaker stems despite the cultivar's strength, so feed moderately. One feed of balanced slow-release fertiliser in early spring is sufficient. Excess nitrogen still produces weaker stems despite the cultivar's strength, so feed moderately. 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 hydrangea 'incrediball'?
Half strength is the safe default for hydrangea 'incrediball' — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
What does over-feeding hydrangea 'incrediball' 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 hydrangea 'incrediball' 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 hydrangea 'incrediball'?
Flush the pot of hydrangea 'incrediball' 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
- Hydrangea 'Incrediball' care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water hydrangea 'incrediball' — the watering schedule
- The houseplant fertiliser schedule — feeding through the year
- NPK ratio explained — what the three numbers on the bottle mean
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- All 3899 fertilising guides in the Growli library