Cardinal

Basil

Zone 10b Save Garden

🌱 45d to harvest Upright

Aromatic as fresh basil oil—Cardinal Italian Basil fills the air with a vivid, sweet-herbal fragrance and a bright, peppery lift.…

Crop Dates

Milestone	Date
Start Indoors	Dec 11th
Last Frost	Jan 1st
Transplant / Sow Outdoors	Feb 19th
Harvest Begins	Apr 5th
Harvest Ends	Dec 31st

Crop Details

Trait	Value
Days to Maturity	45
Sun Requirements	Full Sun
Growth Habit	Upright
Support Needed	None
Planting Depth	Surface
Germination Temp (°F)	70
Min Soil Temp (°F)	60
Min Night Temp (°F)	50
Harden Off (days)	10

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Big Rainbow Tomato

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Cherokee Green Tomato

Frequently Asked Questions

What pest or disease commonly affects Ocimum basilicum (basil), and how can I manage it?

A frequent issue is downy mildew (often seen as yellow patches on the upper leaves with gray-purple growth on the underside), especially in cool, humid conditions. Improve airflow by spacing plants and watering at soil level (not over the leaves), then remove badly infected leaves early to slow spread. If problems persist, use a labeled fungicide for basil downy mildew and avoid harvesting during/soon after treatment so you can follow the label instructions safely.

How often should I water Ocimum basilicum during peak growth, and what soil moisture level is best?

During the main growing phase, keep the soil consistently moist but not waterlogged—aim for the top 1 inch to dry slightly between waterings. In full sun, this is often about every 2–3 days, but adjust based on your container/bed drainage and heat. Water deeply at the base so roots grow downward, since consistently wet foliage and heavy soggy soil increase mildew risk.

How do I tell when cardinal basil (Ocimum basilicum) is ready to harvest?

Harvest when plants are about 40–50 days from sowing and have formed several true leaf sets, typically once stems are leafy and vigorous. Pick by snipping the top 1/3 of growth just above a pair of leaves to encourage branching, and avoid stripping more than about one-third of the plant at a time. For best flavor, harvest in the morning before the leaves heat up, and continue light harvesting regularly to keep plants producing.

Aromatic as fresh basil oil—Cardinal Italian Basil fills the air with a vivid, sweet-herbal fragrance and a bright, peppery lift. Leaves are lush and tender, forming an abundant, upright mound with deep green, velvety foliage that’s prized for its bold flavor and smooth texture. Grow Cardinal for standout pesto, classic tomato-and-basil pairings, and fragrant finishing sprigs that shine in sauces and quick pick-me-ups.

Sowing Tips

Transplant Conditions

Wait until soil reaches 60°F and nights stay above 50°F before moving outdoors. Harden off for 10 days first.

Expert Note

Start Cardinal basil indoors for sturdy transplants, then wait to transplant until nights are reliably warm so the flowers and foliage can develop fully.