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Fertilising guide

How to fertilise Antirrhinum majus 'Rocket Red' (Antirrhinum majus 'Rocket Red')— schedule & NPK

Also called Rocket Red Snapdragon, Tall Red Snapdragon.

More about antirrhinum majus 'rocket red'

About Antirrhinum majus 'Rocket Red'

Antirrhinum majus 'Rocket Red' · also called Rocket Red Snapdragon, Tall Red Snapdragon · flowering

A tall, heat-tolerant snapdragon series bred for long, strong flower spikes that make excellent cut flowers. 'Rocket Red' produces dense columns of rich red dragon-mouth blooms on stems reaching well over half a metre. It thrives in cool-to-mild conditions, performs as a cool-season annual, and rewards deadheading with repeat flushes.

Growth habit: Upright, single-stemmed to lightly branched habit forming tall terminal racemes of two-lipped, snapping flowers. A group I tall snapdragon grown primarily for cutting.

Watch for — Aphids and downy mildew: Aphids cluster on buds; downy mildew shows as pale, distorted growth in cool damp spells. Treat aphids with a water jet or soap and improve ventilation.

What fertiliser antirrhinum majus 'rocket red' actually wants — and why

Antirrhinum majus 'Rocket Red' 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 antirrhinum majus 'rocket 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 antirrhinum majus 'rocket 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 antirrhinum majus 'rocket red':

Feed every 2-4 weeks during active growth with a balanced liquid fertiliser, or work a slow-release feed into the bed at planting. Steady feeding supports the long spikes; ease off once heavy flowering tapers in summer heat. Treat that as every 2-4 weeks 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 antirrhinum majus 'rocket 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 antirrhinum majus 'rocket red'

Half strength is the safe default for antirrhinum majus 'rocket red' — 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 antirrhinum majus 'rocket red' first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the antirrhinum majus 'rocket red' watering schedule.

Signs you are over-feeding antirrhinum majus 'rocket red'

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for antirrhinum majus 'rocket red':

Signs you are under-feeding antirrhinum majus 'rocket red'

If the symptoms point at watering, light or roots rather than nutrition, the full antirrhinum majus 'rocket red' care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

Flush the pot of antirrhinum majus 'rocket red' 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 antirrhinum majus 'rocket red'

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 antirrhinum majus 'rocket red' — frequently asked questions

What fertiliser does antirrhinum majus 'rocket red' 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. Antirrhinum majus 'Rocket Red' 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 antirrhinum majus 'rocket red'?

Feed every 2-4 weeks during active growth with a balanced liquid fertiliser, or work a slow-release feed into the bed at planting. Steady feeding supports the long spikes; ease off once heavy flowering tapers in summer heat. Feed every 2-4 weeks during active growth with a balanced liquid fertiliser, or work a slow-release feed into the bed at planting. Steady feeding supports the long spikes; ease off once heavy flowering tapers in summer heat. Treat that as every 2-4 weeks 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 antirrhinum majus 'rocket red'?

Half strength is the safe default for antirrhinum majus 'rocket red' — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.

What does over-feeding antirrhinum majus 'rocket red' 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 antirrhinum majus 'rocket red' 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 antirrhinum majus 'rocket red'?

Flush the pot of antirrhinum majus 'rocket red' 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.

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