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Fertilising guide

How to fertilise Spear Head (Senecio kleiniiformis)— schedule & NPK

Also called Spear Head, Spearhead Senecio, Reindeer Antlers.

More about spear head

About Spear Head

Senecio kleiniiformis · also called Spear Head, Spearhead Senecio · houseplant

A distinctive South African succulent producing flat, arrowhead- or spear-shaped blue-green leaves on semi-trailing stems. The unusual leaf shape, reminiscent of arrowheads or antlers, makes it a collector's plant. Best in bright indirect to partial direct light with very free-draining soil and infrequent watering. Toxic to pets.

Growth habit: Semi-trailing to mounding succulent with flat spear- or arrow-shaped glaucous leaves on arching stems

Watch for — Leaf scorch and bleaching: Direct afternoon sun damages the flat leaf surfaces, causing pale or brown patches. Shift to a location with bright indirect light or filter direct sun through a sheer curtain.

What fertiliser spear head actually wants — and why

Spear Head 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 spear head: 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 spear head, 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 spear head:

Feed monthly during the growing season (spring and summer) with a balanced liquid fertiliser at half strength. Withhold feed entirely in autumn and winter when growth is minimal. 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 spear head 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 spear head

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

Signs you are over-feeding spear head

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

Signs you are under-feeding spear head

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

Flushing and leaching the salts

Flush the pot of spear head 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 spear head

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 spear head — frequently asked questions

What fertiliser does spear head 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. Spear Head 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 spear head?

Feed monthly during the growing season (spring and summer) with a balanced liquid fertiliser at half strength. Withhold feed entirely in autumn and winter when growth is minimal. Feed monthly during the growing season (spring and summer) with a balanced liquid fertiliser at half strength. Withhold feed entirely in autumn and winter when growth is minimal. 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 spear head?

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

What does over-feeding spear head 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 spear head 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 spear head?

Flush the pot of spear head 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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