Fertilising guide
How to fertilise Spotted Dead Nettle (Lamium maculatum)— schedule & NPK
Also called Spotted Dead Nettle, Spotted Henbit, Purple Dragon Dead Nettle.
More about spotted dead nettle
About Spotted Dead Nettle
Lamium maculatum · also called Spotted Dead Nettle, Spotted Henbit · flowering
A fast-spreading, shade-tolerant groundcover perennial with silver-marked leaves and two-lipped pink, purple, or white flowers from spring through summer. Unlike true nettles, it does not sting. Numerous cultivars offer varied leaf and flower colours. Excellent for brightening shaded areas, edging paths, or spilling over retaining walls. Hardy to zone 3.
Growth habit: Low-growing, mat-forming, rhizomatous herbaceous to semi-evergreen perennial; spreads rapidly by horizontal stolons rooting at nodes
What fertiliser spotted dead nettle actually wants — and why
Spotted Dead Nettle flowers best on poor soil — feed it and you get a lush leafy plant with very few blooms, the exact opposite of what you want.
Little or nothing. Rich, especially nitrogen-rich, soil pushes foliage at the expense of flowers in this plant — lean ground is the technique, not a deficiency.
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 spotted dead nettle: 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 spotted dead nettle, 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 spotted dead nettle:
Apply a balanced slow-release granular fertiliser (e.g. 10-10-10) once in early spring. Over-fertilising with high nitrogen causes lush, flopping growth at the expense of flowers and silver leaf patterning. In very poor soils, a second light liquid feed in early summer helps sustain flowering through summer. In practice: no routine feeding at all for spotted dead nettle — at most a thin compost mulch for soil structure, never a flowering or nitrogen feed.
The dormant-season rule matters more than the exact interval: skip feeding entirely when spotted dead nettle 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 spotted dead nettle
None is the correct answer for spotted dead nettle. The flower-versus-foliage trade-off is the whole point: hold back and you get the display.
Feeding always goes onto already-damp soil, never dry roots — water spotted dead nettle first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the spotted dead nettle watering schedule.
Signs you are over-feeding spotted dead nettle
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for spotted dead nettle:
- Abundant leafy growth and very few flowers (the classic over-rich symptom).
- Soft, floppy stems and a sprawling, leafy habit.
- Scorched edges and salt crust if it has been fed in a container.
Signs you are under-feeding spotted dead nettle
- Effectively never an issue — these plants flower on poverty.
- Only on genuinely dead soil: weak, thin growth and few blooms.
- A short-lived plant in completely spent container compost.
If the symptoms point at watering, light or roots rather than nutrition, the full spotted dead nettle care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
If spotted dead nettle has accidentally been fed and is all leaf, a plain-water flush plus a move to leaner soil resets it; otherwise no flushing is needed because you are not feeding it.
Organic vs synthetic feeds for spotted dead nettle
Organic options
A thin compost mulch for soil structure is the absolute most; mostly, give it nothing. UK/US: leave it lean — no manure, no liquid feed. Poor soil is the active ingredient here.
Synthetic / liquid feeds
None. Synthetic feeds, particularly anything with appreciable nitrogen, directly suppress flowering in spotted dead nettle.
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 spotted dead nettle — frequently asked questions
What fertiliser does spotted dead nettle need?
Little or nothing. Rich, especially nitrogen-rich, soil pushes foliage at the expense of flowers in this plant — lean ground is the technique, not a deficiency. Spotted Dead Nettle flowers best on poor soil — feed it and you get a lush leafy plant with very few blooms, the exact opposite of what you want.
How often should I feed spotted dead nettle?
Apply a balanced slow-release granular fertiliser (e.g. 10-10-10) once in early spring. Over-fertilising with high nitrogen causes lush, flopping growth at the expense of flowers and silver leaf patterning. In very poor soils, a second light liquid feed in early summer helps sustain flowering through summer. Apply a balanced slow-release granular fertiliser (e.g. 10-10-10) once in early spring. Over-fertilising with high nitrogen causes lush, flopping growth at the expense of flowers and silver leaf patterning. In very poor soils, a second light liquid feed in early summer helps sustain flowering through summer. In practice: no routine feeding at all for spotted dead nettle — at most a thin compost mulch for soil structure, never a flowering or nitrogen feed.
What strength of feed for spotted dead nettle?
None is the correct answer for spotted dead nettle. The flower-versus-foliage trade-off is the whole point: hold back and you get the display.
What does over-feeding spotted dead nettle look like?
Abundant leafy growth and very few flowers (the classic over-rich symptom). Soft, floppy stems and a sprawling, leafy habit. Scorched edges and salt crust if it has been fed in a container. Feeding spotted dead nettle at all — especially "to help it flower" — is the defining mistake. Rich soil gives you a big green plant and almost no blooms; restraint is what produces the flowers.
Should I flush the soil of spotted dead nettle?
If spotted dead nettle has accidentally been fed and is all leaf, a plain-water flush plus a move to leaner soil resets it; otherwise no flushing is needed because you are not feeding it.
Keep reading
- Spotted Dead Nettle care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water spotted dead nettle — 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 blue atlas cedar
- How to fertilise golden deodar cedar
- How to fertilise cyprus cedar
- All 8452 fertilising guides in the Growli library