Fertilising guide
How to fertilise Feverfew (Tanacetum parthenium)— schedule & NPK
Also called feverfew, bachelor's buttons, featherfoil.
More about feverfew
About Feverfew
Tanacetum parthenium · also called feverfew, bachelor's buttons · herb
Feverfew is a short-lived, aromatic perennial herb in the daisy family, smothered through summer with small white daisy flowers over feathery, pungent foliage. Easy and self-seeding, it suits cottage borders and herb gardens and attracts pollinators. Traditionally used for headaches, it is toxic to pets and a known contact-allergen for some people.
Growth habit: Bushy, upright, short-lived herbaceous perennial often grown as a biennial, with branching stems, deeply divided aromatic leaves, and abundant small white-and-yellow daisy flowers; self-seeds readily.
What fertiliser feverfew actually wants — and why
Feverfew 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 feverfew: 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 feverfew, 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 feverfew:
Light needs. A spring compost mulch or a single balanced feed at the start of growth is plenty. Over-feeding produces weak, leggy stems that flop and flower poorly. 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 feverfew 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 feverfew
Half strength is a sensible default for feverfew — 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 feverfew first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the feverfew watering schedule.
Signs you are over-feeding feverfew
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for feverfew:
- 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 feverfew
- 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 feverfew care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Pot-grown feverfew 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 feverfew
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 feverfew — frequently asked questions
What fertiliser does feverfew 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. Feverfew 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 feverfew?
Light needs. A spring compost mulch or a single balanced feed at the start of growth is plenty. Over-feeding produces weak, leggy stems that flop and flower poorly. Light needs. A spring compost mulch or a single balanced feed at the start of growth is plenty. Over-feeding produces weak, leggy stems that flop and flower poorly. 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 feverfew?
Half strength is a sensible default for feverfew — enough to fuel regrowth after cutting, gentle enough that the leaves stay aromatic rather than watery.
What does over-feeding feverfew 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 feverfew 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 feverfew?
Pot-grown feverfew 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
- Feverfew care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water feverfew — 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 basil
- How to fertilise herb garden
- How to fertilise mint
- All 2464 fertilising guides in the Growli library