Grosso

Lavender

Zone 10a Save Garden

🌱 365d to harvest Shrub

Breathe in the unmistakable, cool-sweet perfume of Grosso Lavender—an aromatic standout with long, richly colored flower spikes t…

Crop Dates

Milestone	Date
Start Indoors	Direct Sow
Last Frost	Jan 16th
Transplant / Sow Outdoors	Jan 16th
Harvest Begins	Jan 16th
Harvest Ends	Dec 19th

Crop Details

Trait	Value
Days to Maturity	365
Sun Requirements	Full Sun
Growth Habit	Shrub
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	70
Min Soil Temp (°F)	60
Min Night Temp (°F)	45
Harden Off (days)	Not Required

Recommended Companions

Spice Island Rosemary

Frequently Asked Questions

What pest or disease most commonly affects Lavandula × intermedia (Grosso), and how do I manage it?

The most common problem is root rot from poorly drained soil, which shows up as sudden wilting, yellowing, and blackened roots. Water only when the top 1–2 inches of soil are dry, plant in fast-draining ground or raised beds, and avoid wet foliage. If plants decline despite good drainage, remove the affected stems/plant and replant in fresh, well-drained soil to prevent spreading.

How often should I water Grosso lavender during the main growing season?

During active growth, water deeply about once every 7–14 days, but only when the top 1–2 inches of soil feel dry. Grosso (Lavandula × intermedia) tolerates drought once established, so frequent light watering can keep roots too wet and increase rot risk. In hot, windy weather you may need the shorter end of that range; in cool or rainy periods, pause watering entirely.

How can I tell when Grosso lavender is ready to harvest?

Harvest when most flower spikes are in color but the lower florets haven’t opened fully—about when the buds on the spike start to swell and the first flowers begin to show. Use a gentle touch: the spikes should feel firm, not papery or dried out. For best fragrance, cut on a dry morning and harvest before full bloom for the most consistent oil-quality.

Breathe in the unmistakable, cool-sweet perfume of Grosso Lavender—an aromatic standout with long, richly colored flower spikes that hold their fragrance as they dry. Expect a dense, upright habit with silvery foliage that feels softly velvety to the eye, and blossoms that deliver a concentrated, floral-lavender character. Grow Grosso for its showy, long-lasting blooms in the garden and for fragrant potpourri and sachets, or to scent your favorite homemade aromatic blends.

Sowing Tips

Transplant Conditions

Wait until soil reaches 60°F and nights stay above 45°F before moving outdoors.

Expert Note

For Grosso lavender, aim for full sun and excellent drainage—don’t overwater, and keep seedlings/roots from staying wet during establishment.