Mature size & growth rate

How big does Mexican Tarragon (Tagetes lucida) get?

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.

Mature size: 45-75 cm tall and 30-45 cm wide

Watch for — Leggy, sparse growth: Insufficient sun produces lanky stems and weak flavour. Move to the sunniest available spot and pinch growing tips to encourage bushiness.

Indoor size vs how big it gets in the wild

Mexican Tarragon reaches its full size within one growing season — there is no "long-term" size, just how big it gets before you harvest or it dies back. Indoors and in a pot, expect 45-75 cm tall and 30-45 cm wide. A pot, your light levels and a little pruning are what set the final size in a home, far more than the plant's theoretical potential.

It sizes up fast and once, racing from seedling to full size in a single season; after cropping it is finished, so size is a within-season question.

Growth rate and years to mature

Mexican Tarragon is a moderate grower. Realistically, expect a single growing season — it reaches full size in one year, then is done. Its feeding profile backs this up: 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.

Want this turned into the right next pot at the right moment? The pot size calculator and the mexican tarragon repotting guide cover when and how much to size up — pot size is one of the biggest levers on how fast mexican tarragon grows.

How to keep mexican tarragon smaller

You are not stuck with the maximum size. For mexican tarragon specifically, these are the levers, in order of impact:

Choose a compact or dwarf variety of mexican tarragon from the start — that is the most reliable size control for an annual.
Grow it in a smaller container to naturally limit how large it gets.
For some crops, pinching or pruning the growing tips keeps the plant shorter and bushier.
Sow a little later or space plants closer if you specifically want smaller individual plants.

How to grow mexican tarragon bigger or faster

If you want it to fill the space sooner, push the conditions rather than hoping — for mexican tarragon the accelerators are:

Full sun, warm soil and steady water are what drive a crop to full size fastest.
Sow at the right time for your zone so it gets the whole season to size up.
Feed appropriately for the crop and never let it check (stall) from drought or cold.

Light is almost always the ceiling. The mexican tarragon light requirements page covers exactly how bright a spot it needs to grow at its potential instead of stalling.

When mexican tarragon outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for mexican tarragon:

It sprawls beyond its bed or container before harvest — usually a spacing or support issue.
It flops or needs staking once it hits full height.
Once it has fruited or bolted, it is at its final size for good — the next plant is a new sowing.

If it is the pot rather than the room, it is a repotting job, not a goodbye — see the mexican tarragon repotting guide. If you want more of this plant instead of a bigger one, the mexican tarragon propagation guide turns prunings into new plants.

Mexican Tarragon size — frequently asked questions

How big does mexican tarragon get?

Mexican Tarragon reaches 45-75 cm tall and 30-45 cm wide when grown indoors. It sizes up fast and once, racing from seedling to full size in a single season; after cropping it is finished, so size is a within-season question.

Is mexican tarragon slow or fast growing?

Mexican Tarragon is a moderate grower. Expect a single growing season — it reaches full size in one year, then is done. Mexican Tarragon reaches its full size within one growing season — there is no "long-term" size, just how big it gets before you harvest or it dies back.

How long does mexican tarragon take to reach full size?

Roughly a single growing season — it reaches full size in one year, then is done. Light, pot size and feeding move that timeline more than anything else.

How do I keep mexican tarragon smaller?

Choose a compact or dwarf variety of mexican tarragon from the start — that is the most reliable size control for an annual. Grow it in a smaller container to naturally limit how large it gets. For some crops, pinching or pruning the growing tips keeps the plant shorter and bushier. Sow a little later or space plants closer if you specifically want smaller individual plants.

How can I make mexican tarragon grow bigger or faster?

Full sun, warm soil and steady water are what drive a crop to full size fastest. Sow at the right time for your zone so it gets the whole season to size up. Feed appropriately for the crop and never let it check (stall) from drought or cold.