Mature size & growth rate

How big does Red Shiso (Perilla frutescens var. crispa 'Atropurpurea') get?

Also called Purple Perilla, Aka Shiso.

More about red shiso

About Red Shiso

Perilla frutescens var. crispa 'Atropurpurea' · also called Purple Perilla, Aka Shiso · herb

Red Shiso is a deep purple-leaved form of perilla, a mint-family annual key to Japanese cuisine, used to colour pickled plums, flavour dishes, and as a garnish. Its frilled burgundy leaves combine culinary and ornamental appeal. A warm-season herb, it loves sun to part shade, fertile moist soil, and warmth, and self-seeds readily.

Mature size: Around 45-90 cm tall and 30-45 cm wide.

Watch for — Legginess: Unpinched plants in low light grow tall and bare. Pinch tips regularly from young to force bushy, well-branched, leafier growth.

Indoor size vs how big it gets in the wild

Red Shiso 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 around 45-90 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

Red Shiso 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 moderate feeder grown for abundant leaf. work compost into the soil and apply a balanced or nitrogen-leaning liquid feed every few weeks for lush growth. avoid excessive nitrogen, which produces soft leaves at the expense of flavour and colour intensity.

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

How to keep red shiso smaller

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

Choose a compact or dwarf variety of red shiso 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 red shiso bigger or faster

If you want it to fill the space sooner, push the conditions rather than hoping — for red shiso 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 red shiso light requirements page covers exactly how bright a spot it needs to grow at its potential instead of stalling.

When red shiso outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for red shiso:

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 red shiso repotting guide. If you want more of this plant instead of a bigger one, the red shiso propagation guide turns prunings into new plants.

Red Shiso size — frequently asked questions

How big does red shiso get?

Red Shiso reaches around 45-90 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 red shiso slow or fast growing?

Red Shiso is a moderate grower. Expect a single growing season — it reaches full size in one year, then is done. Red Shiso 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 red shiso 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 red shiso smaller?

Choose a compact or dwarf variety of red shiso 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 red shiso 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.