Fertilising guide
How to fertilise Mexican Tarragon (Tagetes lucida)— schedule & NPK
Also called Mexican tarragon, Mexican mint marigold, sweet mace.
More about mexican tarragon
About Mexican Tarragon
Tagetes lucida · also called Mexican tarragon, Mexican mint marigold · herb
Mexican tarragon is a warmth-loving perennial marigold relative grown as an anise-flavoured substitute for French tarragon in hot climates where true tarragon struggles. Native to Mexico and Central America, it forms bushy clumps of glossy leaves topped by small golden-yellow flowers in late summer. It thrives in full sun and heat, tolerates drought, and shrugs off humidity that defeats real tarragon.
Growth habit: Bushy, upright, clumping tender perennial with erect branching stems and narrow glossy aromatic leaves, crowned in late summer to autumn by clusters of small single golden-yellow daisy flowers.
What fertiliser mexican tarragon actually wants — and why
Mexican Tarragon is a lean, aromatic herb — the essential-oil flavour you grow it for is strongest in poor soil, so feeding it actively makes it worse.
Little or nothing. If anything, a very weak balanced feed or a thin compost top-dress — never a rich nitrogen feed, which dilutes the aromatic oils and produces soft, bland, floppy growth.
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 mexican tarragon: 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 mexican tarragon, 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 mexican tarragon:
A light feeder. One application of balanced fertiliser or compost in spring is plenty; over-feeding, especially with nitrogen, dilutes the essential oils and reduces flavour intensity. In practice: a spring compost top-dress at most, and otherwise leave mexican tarragon unfed — lean, sharp-draining soil is exactly what concentrates its flavour.
The dormant-season rule matters more than the exact interval: skip feeding entirely when mexican tarragon 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 mexican tarragon
As weak as it gets for mexican tarragon, or none at all. The flavour-versus-growth trade-off runs the opposite way to leafy crops: restraint is the technique.
Feeding always goes onto already-damp soil, never dry roots — water mexican tarragon first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the mexican tarragon watering schedule.
Signs you are over-feeding mexican tarragon
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for mexican tarragon:
- Lush, soft, fast growth with noticeably weaker scent and flavour.
- Floppy stems, sparse essential oils, and poor cold/wet hardiness.
- Salt crust in containers and scorched leaf tips from over-feeding.
Signs you are under-feeding mexican tarragon
- Rare — these herbs thrive on lean soil.
- Only on truly exhausted soil: pale, thin, very slow growth.
- A short-lived, weak plant in a long-spent container.
If the symptoms point at watering, light or roots rather than nutrition, the full mexican tarragon care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Over-feeding is so unlikely with mexican tarragon that flushing is rarely needed; if a container has had feed, a single plain-water flush and a switch to a leaner, grittier mix resets it.
Organic vs synthetic feeds for mexican tarragon
Organic options
A thin spring mulch of garden compost or leaf-mould is the most these want. UK: a little garden compost; US: a light Espoma Garden-tone top-dress at most. Lean and gritty beats fed and rich every time.
Synthetic / liquid feeds
Generally none for mexican tarragon. At absolute most, a very dilute balanced feed once or twice in a container; in the ground, nothing — synthetic feeds work directly against the flavour.
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 mexican tarragon — frequently asked questions
What fertiliser does mexican tarragon need?
Little or nothing. If anything, a very weak balanced feed or a thin compost top-dress — never a rich nitrogen feed, which dilutes the aromatic oils and produces soft, bland, floppy growth. Mexican Tarragon is a lean, aromatic herb — the essential-oil flavour you grow it for is strongest in poor soil, so feeding it actively makes it worse.
How often should I feed mexican tarragon?
A light feeder. One application of balanced fertiliser or compost in spring is plenty; over-feeding, especially with nitrogen, dilutes the essential oils and reduces flavour intensity. A light feeder. One application of balanced fertiliser or compost in spring is plenty; over-feeding, especially with nitrogen, dilutes the essential oils and reduces flavour intensity. In practice: a spring compost top-dress at most, and otherwise leave mexican tarragon unfed — lean, sharp-draining soil is exactly what concentrates its flavour.
What strength of feed for mexican tarragon?
As weak as it gets for mexican tarragon, or none at all. The flavour-versus-growth trade-off runs the opposite way to leafy crops: restraint is the technique.
What does over-feeding mexican tarragon look like?
Lush, soft, fast growth with noticeably weaker scent and flavour. Floppy stems, sparse essential oils, and poor cold/wet hardiness. Salt crust in containers and scorched leaf tips from over-feeding. Feeding mexican tarragon like a leafy vegetable is the defining mistake — rich nitrogen gives you a big, soft, fast plant whose leaves are watery and bland, with weak winter-rot resistance.
Should I flush the soil of mexican tarragon?
Over-feeding is so unlikely with mexican tarragon that flushing is rarely needed; if a container has had feed, a single plain-water flush and a switch to a leaner, grittier mix resets it.
Keep reading
- Mexican Tarragon care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water mexican tarragon — 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