How to Grow Lavender Grand Slam
Lavender Grand Slam
Lavandula × intermedia 'Grand Slam'
shrubLavender Grand Slam is a hybrid lavender cultivar known for its exceptional vigor and abundant purple flower spikes that tower above the foliage. It produces fragrant blooms excellent for cutting and drying, and attracts pollinators while providing year-round ornamental value with its silvery-green foliage.
When should you plant Lavender Grand Slam in your zone?
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Example Lavender Grand Slam timeline · Pittsburgh, PA (Zone 6b)
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Plant Lavender Grand Slam
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Lavender Grand Slam
Around Jul 16≈ 90 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Lavender Grand Slam dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 5b-9b, with best performance in zones 6-8
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Establishment
4-6 weeksYoung transplant with minimal foliage establishing root system
Keep soil consistently moist but not waterlogged for first 4-6 weeks. Avoid fertilizing. Provide afternoon shade in hot climates.
Vegetative Growth
6-8 weeksPlant develops silvery-green mounding foliage with increasing stem production
Water moderately during dry spells. Avoid high-nitrogen fertilizers. Mulch lightly with gravel rather than organic matter to preserve drainage.
Budding & Flowering
8-12 weeksTall flower spikes (12-18 inches) emerge with dense purple florets
Deadhead spent flowers to encourage additional blooms. Support tall stems in wind-prone areas. Minimal watering needed.
Peak Bloom & Harvest
4-6 weeksMaximum flower production with intense fragrance; ideal cutting stage
Harvest flowers in mid-morning after dew dries but before heat of day. Cut stems just below flower spikes for best vase life.
Dormancy
3-4 monthsFoliage persists but flowering diminishes; plant enters rest phase
Reduce watering to minimal levels. Do not prune severely in fall. Light shearing in early spring before new growth. Deadhead old flowers if desired.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick beetles; encourage natural predators; insecticidal soap as last resort
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Ensure excellent drainage; avoid overwatering; plant in raised beds if necessary; remove infected plants
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Increase humidity; strong water spray; neem oil or insecticidal soap if severe
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Improve air circulation; avoid wetting foliage; remove affected leaves; apply fungicide if necessary
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Prune affected shoots; insecticidal soap; monitor for early intervention
Uses
Culinary flavoring and tea
CulinaryLavender flowers add a floral, slightly sweet note to baked goods, desserts, and beverages. Dried lavender buds can be steeped into tea for relaxation or used as a garnish on salads and savory dishes. [source]
Relaxation and stress relief
MedicinalLavender is widely used in aromatherapy, essential oils, and herbal preparations for its calming properties. Studies support its use for anxiety reduction, improved sleep quality, and general relaxation. [source]
Natural fragrance and pest deterrent
HouseholdDried lavender flowers freshen linens, wardrobes, and living spaces with natural fragrance. The strong scent also helps repel moths, fleas, and other household insects. [source]
Cut flowers and dried arrangements
CraftGrand Slam's tall stems and abundant flowers make it exceptional for fresh cut arrangements and dried bouquets. Its longevity and fragrance make it a premium florist choice. [source]
Pollinator magnet
WildlifeLavender is highly attractive to bees, butterflies, and other pollinators, making it essential for supporting beneficial insect populations in gardens and landscapes. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Cut flower spikes in mid-morning when 50-75% of florets have opened. Leave at least 2-3 inches of stem on plant. Harvest throughout summer (June-September in most zones) for continuous blooms. Dry flowers by hanging upside-down in a cool, dark, well-ventilated area for 2-3 weeks.
Fun Facts
- 🌱 Lavender Grand Slam can grow 24-36 inches tall and equally wide, making it one of the larger lavender cultivars available.
- 🌱 The name 'Grand Slam' refers to its exceptional performance in landscape trials and its ability to win multiple horticultural awards.
- 🌱 Lavender has been used for over 2,500 years for fragrance, medicine, and pest control, with ancient Romans using it to scent bathwater.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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