How to Grow Shisos Canada

Quick Facts

Factor	Value
Drainage	Moist but well-drained (RHS); NC State: rich, moist to dry, tolerates high organic matter, good drainage, occasionally wet soil acceptable, highly resistant to heat and drought.
Lifecycle	Bushy, upright annual with toothed, aromatic, often red or purple leaves and insignificant white flower spikes in late summer (RHS). NC State: grows quickly and aggressively, self-seeds prolifically via wind dispersal, and is described as high maintenance as a result.
Edible parts	leaves, seeds

Growth Stages

Stage	BBCH	Notes
Sowing and establishment	0	Propagate by seed (RHS; NC State). Grown in full sun or partial shade, in fertile, moist but well-drained soil (RHS); NC State notes it is highly resistant to heat and drought once established, spaced under 12in apart.
Growth and spread management	3	NC State: grows quickly and aggressively, self-seeding prolifically via wind dispersal, and is high maintenance as a result -- pinching off flowers before they go to seed is recommended to help slow the spread, an important step given the plant's invasive listing in several US states.
Flowering	6	RHS: insignificant, 2-lipped white flowers borne in erect spikes in late summer.
Harvest	8	RHS: used as a herb, the aromatic leaves harvested through the growing season; also used as a foliage carpet bedding plant. NC State: fast, aggressive growth means leaves are available across much of the season.

Harvest & Storage

When to pick: RHS: grown as a herb as well as a foliage bedding plant; aromatic leaves are the part used. NC State: fast, aggressive growth with prolific self-seeding, so leaves are available through much of the growing season.

Storage

Used fresh -- neither source gives a specific drying or storage method for this crop.

Shiso Photo Gallery

Used as bedding

Shiso used as a foliage bedding plant.

A flower spike

A shiso flower spike.

What the research guides add

Shiso is easy, and that is the problem: both sources below warn that it self-seeds prolifically, and one treats it as an invasive weed.

• An annual member of the mint family that reseeds itself each year; unlike garden mints it does not spread by runners (Missouri Department of Conservation). (Missouri Department of Conservation)
• It grows best in full sun to partial shade in rich, moist to dry soil. (NC State Extension)
• It self-seeds prolifically, and pinching off the flowers before they go to seed helps slow the spread of the wind-dispersed seeds (NC State). Missouri advises weeding before flowering and seed set. (NC State Extension, Missouri Department of Conservation)
• NC State says it is classified as invasive by the NC Invasive Plant Council and listed as invasive in Virginia, West Virginia, Tennessee and Kentucky. Missouri calls it a nonnative, invasive species that should not be planted or allowed to spread, and says the Missouri legislature passed a ban on selling it in 2025. (NC State Extension, Missouri Department of Conservation)

Shiso in Canada: climate data

Frost dates and frost-free days are the median values for the stations in Environment and Climate Change Canada climate normals with the highest data-quality rating (1981–2010 normals).

Sources for this section

• Missouri Department of Conservation: Beefsteak Plant (Perilla Mint)
• NC State Extension: Perilla frutescens (Plant Toolbox)

Section researched and checked on 24 October 2026 by the SoilCommander Editorial Team. How we check facts: editorial policy.

Sources

The full list of 2 sources behind this guide (North Carolina State University Extension (Plant Toolbox), Royal Horticultural Society) is in the references of our UK guide to shiso; they describe the plant itself, which is the same wherever it grows.