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Gros Bleu

Lavender
Zone 7b Save Garden

Planting Schedule

Add Gros Bleu to your garden to build a schedule and get reminders.
Botanical illustration of Gros Bleu
365d to harvest

Breathe in the first rush of cool, resinous fragrance—Gros Bleu blooms with a bold, lavender-blue presence that feels almost velvety in the air. Its aromatic flower spikes rise on sturdy, upright stems, offering a richly textured harvest of deep-toned blossoms that dry beautifully for long-lasting scent. Grow Gros Bleu for a perennial showpiece that perfumes the garden year after year, ideal for sachets, potpourri, and fragrant bundles.

Crop Dates

Growing note: Zone 7b has only 201 frost-free days — shorter than this crop's 365-day maturity. Outdoor planting is not viable; use protected cultivation.
MilestoneDate
Last FrostApr 10th
Growing ApproachProtected Environment Only

Crop Details

TraitValue
Days to Maturity365
Sun RequirementsFull SunFull sun
Growth HabitShrub
Support NeededNone
Planting DepthNormal
Germination Temp (°F)70
Min Soil Temp (°F)60
Min Night Temp (°F)40
Harden Off (days)7

Today's Conditions

Outdoor planting for Gros Bleu in Zone 7b typically begins around Indoor Lights Only. Wait until soil reaches at least 60°F before transplanting Gros Bleu.

Garden Alerts

Zone 7b has only 201 frost-free days — shorter than this crop's 365-day maturity. Outdoor planting is not viable; use protected cultivation.

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Frequently Asked Questions

How often should I water Lavandula × intermedia during its main growing season?
During the main growing phase, water deeply only when the top 1–2 inches of soil are dry, then let it dry out again before the next watering. In hot summer conditions this may be roughly 1–2 times per week, but the key is soil dryness rather than a fixed schedule; avoid frequent light watering that keeps roots wet. Mulch sparingly and keep mulch pulled back from the crown to prevent moisture buildup.
How do I tell when Lavandula × intermedia (Gros Bleu) is ready to harvest?
Harvest when the flower spikes are mostly formed and the buds are just starting to open—about 30–50% of the florets should be open for the best fragrance and color. Cut stems in the morning after dew dries, before the hottest part of the day, and avoid harvesting after the flowers fully turn brown. For long color, you can do a second light harvest after regrowth if plants stay healthy.
Botanical illustration of Gros Bleu

Breathe in the first rush of cool, resinous fragrance—Gros Bleu blooms with a bold, lavender-blue presence that feels almost velvety in the air. Its aromatic flower spikes rise on sturdy, upright stems, offering a richly textured harvest of deep-toned blossoms that dry beautifully for long-lasting scent. Grow Gros Bleu for a perennial showpiece that perfumes the garden year after year, ideal for sachets, potpourri, and fragrant bundles.

Today's Conditions

Outdoor planting for Gros Bleu in Zone 7b typically begins around Indoor Lights Only. Wait until soil reaches at least 60°F before transplanting Gros Bleu.

Garden Alerts

Zone 7b has only 201 frost-free days — shorter than this crop's 365-day maturity. Outdoor planting is not viable; use protected cultivation.

Sowing Tips

Soil Temperature

Direct sow or transplant when soil at planting depth holds 60°F for reliable germination and early growth.

Expert Note

Start with a very light, fast-draining seed-start mix and avoid overwatering—lavender fails more from soggy roots than cold weather.