Ao Shiso

Shiso

Zone 5a Save Garden

🌱 45d to harvest Upright

Unfurling with a cool, aromatic lift, Ao Shiso leaves are prized for their vivid, sea-green color and a distinctly fresh shiso fr…

Crop Dates

Milestone	Date
Start Indoors	Apr 10th
Last Frost	May 8th
Transplant / Sow Outdoors	Jun 5th
Harvest Begins	Jul 20th
Harvest Ends	Sep 30th

Crop Details

Trait	Value
Days to Maturity	45
Sun Requirements	Part Sun
Growth Habit	Upright
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	70
Min Soil Temp (°F)	50
Min Night Temp (°F)	50
Harden Off (days)	7

Recommended Companions

Sicilian Violet Radish

Tokiwa Cucumber

Manny Cucumber

Tsurusawa Japanese Climbing Cucumber

Wisconsin SMR 58 Cucumber

Long Feng Cucumber

Frequently Asked Questions

How do I prevent and treat downy mildew on Ao Shiso (Perilla) leaves?

Downy mildew on Ao Shiso shows as pale yellow spots on top of leaves with a gray-purple fuzz underneath, usually after humid weather. Remove and discard infected leaves promptly, improve airflow, and water at the soil line instead of overhead. If it keeps spreading, apply a labeled organic fungicide such as copper or potassium bicarbonate and repeat according to label directions until new growth stays clean.

During the 45-day growing period, how often should I water Ao Shiso and what soil moisture should I aim for?

For most of the 45-day cycle, keep soil consistently evenly moist but not soggy—water when the top 1 inch feels dry to the touch. Aim for deep watering so the root zone stays hydrated, especially after germination when Ao Shiso is establishing. In part-sun beds, cut back slightly during cooler weeks to prevent waterlogged soil that encourages leaf diseases.

How can I tell when Ao Shiso is ready to harvest for the best leaf flavor?

Start harvesting around 40–45 days when plants have multiple fully expanded leaves and stems are sturdy enough to pinch without tearing. Pick leaves in the morning, choosing leaves that are deep green and crisp (tender but not tiny), and avoid harvesting more than about one-third of the plant at a time. Regular picking encourages branching, but stop light harvesting once flowering begins so the leaves don’t turn tougher and more bitter.

Unfurling with a cool, aromatic lift, Ao Shiso leaves are prized for their vivid, sea-green color and a distinctly fresh shiso fragrance that turns gardens into sensory landscapes. The foliage is tender yet substantial, with softly crinkled texture and a crisp, clean bite that shines in quick, bright preparations—ideal for wrapping, garnishing, and flavoring vinegars and sauces. Grow Ao Shiso for reliable, fast harvest (about 45 days) and enjoy a steady stream of fragrant leaves from early summer onward.

Sowing Tips

Transplant Conditions

Wait until soil reaches 50°F and nights stay above 50°F before moving outdoors. Harden off for 7 days first.

Expert Note

Start indoors early for a quicker harvest, but keep seedlings in cool-to-mild conditions and transplant only after nights are reliably warm to avoid slow growth.