Allium 'Globemaster' bulbs produce huge, rounded purple flowerheads up to 15 cm across on tall, st...Allium 'Globemaster' bulbs produce huge, rounded purple flowerheads up to 15 cm across on tall, sturdy stems in summer, creating bold architectural interest in sunny borders. These RHS award-winning perennials are low maintenance, drought tolerant, and highly attractive to bees and other pollinators. Growing to an eventual height of 80 cm with a spread of 20 cm, they thrive in sunny spots with well-drained soil. Plant bulbs 10–15 cm deep and apart during autumn for best results. Perfect for borders, cottage gardens, and wildlife-friendly planting, they offer spectacular visual impact throughout the flowering season.
The Marshalls Garden Allium Globemaster Bulbs are an ideal choice for gardeners looking to add striking, architectural height and vibrant purple color to sunny flower borders. These RHS award-winning perennials are perfect for those who want a low-maintenance, drought-tolerant plant that also serves as a pollinator magnet; however, note that these bulbs require well-drained soil to prevent rotting during the dormant winter months.
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Model Part Number
1306943
Brand
Marshalls Garden
Extended Product Information
FAQs
How deep should I plant Allium Globemaster bulbs?
You should plant the bulbs 10–15 cm deep in the soil.
Are these bulbs deer or rabbit resistant?
While not strictly guaranteed, Alliums generally have an onion-like scent that most browsing mammals tend to avoid.
Can I grow these in pots?
Yes, they can grow in deep containers provided the container has good drainage and the soil does not become waterlogged.
When is the best time to plant them?
The ideal time for planting is during the autumn.
Do I need to dig them up every year?
No, Allium Globemaster bulbs are hardy and can be left in the ground year-round provided the soil is well-drained.
Troubleshooting
Bulbs failing to emerge in spring
Often caused by soil that is too wet during winter. Ensure site drainage is improved before replanting.
Stunted growth or poor flowering
Usually a result of insufficient sunlight. Ensure the plants are in a spot with full sun exposure.
Pros and Cons
Pros
Large, impressive flower size
Sturdy stems that resist wind
Excellent for supporting local bee populations
Low maintenance requirements
Drought-tolerant once established
Cons
Requires well-drained soil to survive winter
Needs full sun for optimal flowering
Only blooms during the summer season
Setup, Compatibility & Care
Planting Time: Plant bulbs during the autumn months to allow roots to establish before winter.
Depth and Spacing: Bury each bulb 10–15 cm deep, keeping them 10–15 cm apart to ensure adequate airflow and room for the developing root systems.
Soil Preparation: Ensure the planting site has excellent drainage. If your soil is heavy clay, mix in horticultural grit or compost to improve drainage.
Sunlight Requirements: Choose a location that receives full sun throughout the day.
Post-Flowering Care: Leave the foliage to die back naturally after the flowers have faded to allow the bulb to store energy for the following season. Avoid removing the leaves until they have turned yellow and withered.