Shiso (perilla)

Sun

Full sun to partial shade; afternoon shade helps in hot, dry gardens.

Water

Keep evenly moist but not waterlogged; container plants may need daily watering in hot weather.

Soil

Fertile, well-drained soil enriched with compost; tolerates slightly acidic to neutral conditions.

Height

2-3 ft (0.6-0.9 m)

Spread

1-2 ft (0.3-0.6 m)

Flowers

Small white to pale pink flowers in upright spikes in late summer and autumn.

Foliage

Broad, pointed, toothed leaves, often crinkled; green, purple or green above and purple beneath, depending on the form.

Growth

Fast in warm weather.

Care needed

Low

• Pollinators
• Heat tolerant
• Low allergen
• Fragrant
• Edible

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Easy

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   0.5 ft (0.15 m)

2. After 1 year

   2.5 ft (0.75 m)

   full size

Full size in one season.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Invasive in

the US

In the garden

Spreads vigorously: plan to contain it.

Growth rate

Fast

• Plant out after the last frost, once the soil has warmed and nights are reliably mild.
• Space plants 12-18 in (30-45 cm) apart for good airflow and easy picking.
• Water at soil level when the surface starts to dry; do not let pots dry out completely.
• Add compost before planting; feed container plants lightly with a balanced liquid fertiliser if growth slows.
• Mulch once the soil is warm to conserve moisture.
• Remove flower spikes before seeds ripen unless you intend to collect seed.

Pruning. Pinch out growing tips when plants are about 6-8 in (15-20 cm) tall to encourage branching. Continue picking shoot tips and removing flower spikes through summer to keep plants leafy.

Pick individual leaves once plants are well established and the leaves are large enough to use; young, tender leaves generally have the best texture. Snip leaves or short shoot tips regularly, leaving enough foliage for continued growth, and harvest before frost kills the plants.

Early spring

Sow fresh seed indoors in a warm, bright place; press onto moist seed compost and cover only very lightly.

Late spring

Harden off seedlings and plant outside after frost risk has passed and the soil has warmed.

Early summer

Pinch out growing tips and begin picking leaves from established plants.

Summer

Keep soil evenly moist and check tender shoots and leaf undersides for pests.

Late summer

Remove flower spikes to prolong leaf production and prevent unwanted seedlings.

Autumn

Harvest remaining usable leaves before frost and remove dead plants; avoid scattering ripe seed.

• Plant purple-leaved forms among green vegetables for strong foliage contrast in a kitchen garden.
• Grow in containers beside an outdoor cooking area for convenient picking.
• Repeat small groups along a sunny herb-bed edge for an informal, leafy rhythm.
• Combine with parsley, basil and chives in an edible display with contrasting leaf shapes.

Garden styles it suits: Potager (kitchen garden), Edible landscape, Japanese, Sensory garden, Small-space and Cottage garden.

Plant it with: Basil, Parsley, Chives, Lettuce, Tomatoes and French marigolds.

Wildlife: Flowers attract bees and other small pollinating insects. Removing flower spikes to prevent self-seeding also removes this nectar source.

• Slugs and snails can strip young seedlings; protect new plants with barriers, hand-picking or a locally approved iron-phosphate bait.
• Aphids cluster on soft shoot tips; wash them off with water and repeat as needed.
• Spider mites can cause pale stippling in hot, dry conditions; keep plants adequately watered and rinse leaf undersides regularly.
• Poor or uneven germination is common with old or dormant seed; use fresh seed, keep it warm and evenly moist, and allow several weeks for emergence.

Leaves of culinary shiso are not known to be toxic to people in normal food quantities, though allergies can occur. Perilla can cause severe, sometimes fatal lung injury in grazing livestock, including horses; keep all plant material, especially flowering and seed-bearing plants, away from pasture and hay. Toxicity to cats and dogs is not well established, so do not encourage them to eat it. Concentrated oils should not be treated as equivalent to culinary leaves.

Where it spreads. Self-seeds readily and is invasive in parts of the eastern and central United States, particularly the Southeast and Mid-Atlantic; it appears on invasive-plant lists in states including Virginia, Tennessee and Pennsylvania. It can escape into disturbed ground, stream margins and woodland edges. Check local guidance before planting and prevent seed production where escape is a concern.

• Coleus (Coleus scutellarioides)

  Coleus often has strongly patterned or multicoloured leaves and lacks shiso's characteristic culinary aroma; do not identify an edible plant by purple foliage alone.

• Purple basil (Ocimum basilicum)

  Basil usually has smoother, less sharply toothed leaves and a recognisable basil scent; shiso leaves have more pronounced teeth and often a crinkled surface.

The species name frutescens means 'becoming shrubby', referring to its bushy growth.

Propagation. Grow from seed sown indoors in spring or directly outdoors after frost in warm soil. Germination can be erratic, especially with older seed; surface-sow or cover very lightly and keep at about 65-75°F (18-24°C). Seedlings may differ in leaf colour and flavour if different forms have crossed.

Accepted botanical name

Perilla frutescens

In the US and Canada

Introduced in Canada and the lower 48 states.

Native range

Assam, Bangladesh, China South-Central, China Southeast, East Himalaya, India, Japan, Jawa, Khabarovsk, Korea, Laos and Myanmar.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.