Growing Shiso: A Simple Guide for a Thriving Herb Garden

Choosing the Right Shiso Variety

Before even touching soil, deciding on your shiso variety sets the tone for your gardening adventure. Two popular types stand out: green shiso (Perilla frutescens var. crispa) and red shiso (Perilla frutescens var. purpurea).

• Green Shiso: Mild, herbal, slightly minty, perfect for salads, sushi, and garnishing cocktails.
• Red Shiso: Earthier, aromatic, beloved for pickles, umeboshi plums, or as natural food coloring.

Both grow similarly, but red shiso flaunts striking burgundy hues, making it a handsome addition to edible landscaping.

Starting Shiso from Seed

Growing shiso from seed thrills me every season. Seeds germinate consistently when given warmth and moisture.

Start indoors 4 to 6 weeks before the last frost, or sow directly outdoors once temperatures hover around 65°F (18°C).

Here's a quick guide I swear by:

1. Use damp seed-starting mix, pressing tiny seeds gently onto the surface—no need to bury them deeply.
2. Cover trays loosely with plastic wrap to maintain humidity and speed up germination. Expect sprouts in about 7 to 14 days.
3. Keep seedlings near a sunny window or under grow lights, thinning them to strongest seedlings once established.

Ideal Growing Conditions

Shiso adores sunlight—at least 6 hours daily—and fertile, well-draining soil enriched with compost.

In my temperate climate garden, shiso thrives vigorously outdoors once daytime temperatures are consistently above 65°F (18°C) and nights above 50°F (10°C).

Pro tip: In hotter climates, provide dappled shade during peak afternoon hours to prevent leaf scorching and bitterness.

Planting and Spacing

Transplant outdoor seedlings carefully, spacing plants about 12 to 18 inches (30 to 45 cm) apart.

Shiso grows faster than you'd imagine, rapidly filling out into bushy mounds about 2 to 3 feet (60 to 90 cm) tall.

Care and Maintenance

Watering and Feeding

Consistent moisture, without waterlogging, keeps shiso happily flourishing. Weekly deep watering proves sufficient in most places, but check soil regularly during hot or dry spells.

Feed plants organically every 4 to 6 weeks with fish emulsion or diluted compost tea—trust me, it'll show in lush foliage.

Pinching and Pruning

To encourage bushiness, pinch the growing tips regularly. This habit yields less leggy growth and more flavorful leaves.

Remove flowers as soon as they appear unless you're saving seeds—flowering signals shiso to slow leaf production.

Common Pests and How to Handle Them

Shiso, thankfully, avoids attracting hordes of pests. Occasionally, aphids or spider mites make an appearance, manageable through natural remedies.

• Aphids: Blast gently with water or apply insecticidal soap.
• Spider mites: Spray undersides of leaves with neem oil every few days until controlled.

Harvesting Shiso Leaves

Harvesting shiso defines late spring and summer for me—a rhythmic pleasure punctuated by humming bees. Snip mature leaves individually or trim stems lightly, never taking more than a third at once.

Morning harvests ensure peak flavor and essential oils. Trust your nose; freshly picked shiso offers a profound aromatic reward.

Harvest gently and frequently—it's an herb eager to regrow and deliver more.

Storing and Preserving Shiso

Fresh shiso leaves store briefly in the refrigerator, wrapped in a slightly damp paper towel to retain freshness and texture.

For longer storage, drying or freezing works wonders. Dried shiso retains flavor beautifully for teas or seasoning salts; frozen leaves lend authenticity to off-season dishes or cocktails.

Saving Shiso Seeds

Allow some plants to flower and form seed pods at season's end. Once pods dry and darken, I gently harvest and shake them into paper envelopes.

Stored in a cool, dry place, these seeds reliably germinate next season—gardening with shiso becomes a continuous cycle inspired year after year.

Growing shiso rewards patience, curiosity, and flavor-seeking gardeners. Provide shiso rich, well-drained soil, partial sunlight, and regular watering—allowing the plant space to breathe and flourish. Regular pruning encourages lush foliage, boosting both harvest and flavor. By thoughtfully tending to this aromatic herb, you'll savor its vibrant leaves that lend complexity to your kitchen adventures. Treat shiso well, and it will generously repay you, season after season.