Fertilising guide
How to fertilise Marsh Woundwort (Stachys palustris)— schedule & NPK
Also called Marsh Woundwort, Marsh Hedgenettle, Clown's Woundwort.
More about marsh woundwort
About Marsh Woundwort
Stachys palustris · also called Marsh Woundwort, Marsh Hedgenettle · herb
Stachys palustris is a native British perennial herb in the mint family (Lamiaceae), found along riverbanks, ditches, marshes, and wet meadows across the UK, Europe, and Asia. It produces upright square stems bearing whorls of hooded, lipped, pinkish-purple flowers in mid-summer that attract bumblebees. The most critical care point is to provide consistently moist to wet soil and to contain the spreading rhizomes, which can colonise far beyond the original planting. It is not listed by the ASPCA and formal pet-toxicity status is unconfirmed; treat as mildly toxic as a precaution.
Growth habit: Upright, patch-forming herbaceous perennial spreading vigorously by shallow tuberous rhizomes; square hairy stems and opposite, stalkless, lance-shaped leaves with serrated margins.
Watch for — Leaf miner damage (Amauromyza morionella): The larvae of this Agromyzid fly create pale linear then blotch mines in the leaves; damage is cosmetic and rarely severe, but affected leaves should be removed to prevent population build-up.
What fertiliser marsh woundwort actually wants — and why
Marsh Woundwort is a soft, fast leafy herb that you harvest hard — a modest balanced feed keeps tender growth coming without tipping it into bland or bolting.
A balanced general feed (even N-P-K) at modest strength — enough nitrogen to keep replacing the leaves you pick, but not so much that flavour thins or it bolts to seed.
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 marsh woundwort: 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 marsh woundwort, 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 marsh woundwort:
No routine fertilisation required in fertile, moist garden soils; on very poor sandy ground a balanced spring feed can support healthy flowering. In practice: a balanced liquid feed every few weeks through the main growing and harvesting season (spring through early autumn), more often the harder you are picking it.
The dormant-season rule matters more than the exact interval: skip feeding entirely when marsh woundwort 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 marsh woundwort
Half strength is a sensible default for marsh woundwort — enough to fuel regrowth after cutting, gentle enough that the leaves stay aromatic rather than watery.
Feeding always goes onto already-damp soil, never dry roots — water marsh woundwort first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the marsh woundwort watering schedule.
Signs you are over-feeding marsh woundwort
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for marsh woundwort:
- Fast, soft, pale growth with diluted, less aromatic flavour.
- Early bolting (running to flower) and a bitter edge.
- Salt crust and scorched tips on container plants.
Signs you are under-feeding marsh woundwort
- Pale, slow regrowth after cutting and small leaves.
- A tired, stalled plant that cannot keep up with harvesting.
- Yellowing older leaves in a long-spent pot.
If the symptoms point at watering, light or roots rather than nutrition, the full marsh woundwort care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Pot-grown marsh woundwort builds up feed salts quickly — water until it drains each time and flush the pot with plain water every few weeks, especially on a sunny windowsill.
Organic vs synthetic feeds for marsh woundwort
Organic options
A diluted seaweed feed or worm-casting tea keeps soft growth coming without overdoing it. UK: dilute seaweed or Westland; US: Espoma Garden-tone or Neptune's Harvest. Gentle, hard to overdo, flavour-friendly.
Synthetic / liquid feeds
A balanced liquid feed at half strength through harvesting — UK: Phostrogen, Baby Bio or Westland; US: Miracle-Gro all-purpose at half strength. Fast regrowth; just do not overdo the nitrogen.
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 marsh woundwort — frequently asked questions
What fertiliser does marsh woundwort need?
A balanced general feed (even N-P-K) at modest strength — enough nitrogen to keep replacing the leaves you pick, but not so much that flavour thins or it bolts to seed. Marsh Woundwort is a soft, fast leafy herb that you harvest hard — a modest balanced feed keeps tender growth coming without tipping it into bland or bolting.
How often should I feed marsh woundwort?
No routine fertilisation required in fertile, moist garden soils; on very poor sandy ground a balanced spring feed can support healthy flowering. No routine fertilisation required in fertile, moist garden soils; on very poor sandy ground a balanced spring feed can support healthy flowering. In practice: a balanced liquid feed every few weeks through the main growing and harvesting season (spring through early autumn), more often the harder you are picking it.
What strength of feed for marsh woundwort?
Half strength is a sensible default for marsh woundwort — enough to fuel regrowth after cutting, gentle enough that the leaves stay aromatic rather than watery.
What does over-feeding marsh woundwort look like?
Fast, soft, pale growth with diluted, less aromatic flavour. Early bolting (running to flower) and a bitter edge. Salt crust and scorched tips on container plants. Over-feeding marsh woundwort with strong nitrogen is the usual mistake — it grows fast and lush but the leaves turn bland and it bolts to flower sooner, ending the useful harvest early.
Should I flush the soil of marsh woundwort?
Pot-grown marsh woundwort builds up feed salts quickly — water until it drains each time and flush the pot with plain water every few weeks, especially on a sunny windowsill.
Keep reading
- Marsh Woundwort care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water marsh woundwort — 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 rayed tansy
- How to fertilise white sage brush
- How to fertilise beach wormwood
- All 10153 fertilising guides in the Growli library