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Home > AUTUMN PLANTED BULBS > Alliums > Allium Giganteum
Allium Giganteum
Allium Giganteum Allium Giganteum Allium Giganteum Bulbs grown in a clump
Allium Giganteum is one of the tallest varieties of alliums as it will reach up to 1.5m tall, with its spectacular ball-shaped blooms made up of masses of tiny bright Purple flowers that will reach 20cm in diameter.
 
To get the best from your Alliums, we suggest planting them in groups along the back of your borders or on their own interspersed between your other flowers and plants. Once planted in the autumn, they will not disappoint once they flower in late spring. 
 
These majestic beauties really are fast becoming all an round favourite amongst the gardening community, new and old! 

How to plant Alliums

  • Plant Alliums in the Autumn for Spring flowering.
  • Choose a location to plant your Allium Bulbs, they like to be in full sunlight and well-drained soil.

Planting Alliums in the Garden

  • Once you have found the perfect spot in your garden to grow your Alliums, you need to dig holes in the flower bed that are three times the diameter of the bulb. For example, if the bulb is 5cm (2") in size then it needs to be planted 15cm (6") deep.
  • Plant the bulbs about 20-30cm (8-12") apart. For impact, plant in groups.
  • Alliums work well in rockeries and crowded gardens as they don't take up much space.
  • Add horticultural grit to heavy soil to improve water drainage. 
  • The Allium bulbs need to be planted pointy end up.
  • Water the bulb well once in situ.
  • To help the soil drain well it is also beneficial to spread mulch, wood chips and organic matter over the entire planting area.
  • Alliums will flower around May/June.
  • Cut the Alliums back at the end of their blooming season. They will then continue to grow in your garden year on year with very little maintenance.

Planting Alliums in Pots 

  • Plant Alliums the same depth for pots as in the garden. Plant three times the diameter of the bulb. For example, if the bulb is 5cm (2") in size then it needs to be planted 15cm (6") deep.
  • For a garden with limited space, you may want to produce a fuller display of spring flowers by layering your bulbs like a lasagne. Simply plant your bulbs deeper to start with, with the largest or latest flowering bulbs further down, moving to the smallest and earliest flowering in the top layer. The shoots from the lower bulbs will find their way around the other bulbs. If you are planting the Alliums first, allow 10cm (4") of soil underneath the bulbs.
  • Add horticultural grit to heavy soil to improve water drainage. 
  • The Allium bulbs need to be planted pointy end up.
  • Water the bulb well once in situ.
  • To help the soil drain well it is also beneficial to spread mulch, wood chips and organic matter over the entire planting area.
  • Alliums will flower around May/June.
  • Cut the Alliums back at the end of their blooming season. They will then continue to grow in your garden year on year with very little maintenance.

Description

Allium Giganteum is one of the tallest varieties of alliums as it will reach up to 1.5m tall, with its spectacular ball-shaped blooms made up of masses of tiny bright Purple flowers that will reach 20cm in diameter.
 
To get the best from your Alliums, we suggest planting them in groups along the back of your borders or on their own interspersed between your other flowers and plants. Once planted in the autumn, they will not disappoint once they flower in late spring. 
 
These majestic beauties really are fast becoming all an round favourite amongst the gardening community, new and old! 

Additional Information

Delivery / Returns

Spring Flowering Bulbs are delivered in the Autumn

Delivery and P&P

Spring Flowering Bulbs are dispatched from September to November.
All orders should be dispatched within 3-5 working days during this time. (Unless otherwise stated on the Shipping est.)
Postage cost to mainland UK (excluding N.Ireland) is £4.99.
Orders over £50 qualify for FREE delivery.
Unfortunately, we are not currently delivering to the EU. See Delivery page.
When your order is due for dispatch, you will receive a tracking email from us to track your parcel.
Your parcel will be sent on a 48 hour tracked service with Yodel.

Returns and Refunds

You have the right to cancel your order at any time before it is dispatched.
All returns must be returned at your cost within 7 days of receipt.
Payment for the returned goods will be refunded within 7 days of the goods being received by us, less the postage charges. 



Planting & Growing Instructions

How to plant Alliums

  • Plant Alliums in the Autumn for Spring flowering.
  • Choose a location to plant your Allium Bulbs, they like to be in full sunlight and well-drained soil.

Planting Alliums in the Garden

  • Once you have found the perfect spot in your garden to grow your Alliums, you need to dig holes in the flower bed that are three times the diameter of the bulb. For example, if the bulb is 5cm (2") in size then it needs to be planted 15cm (6") deep.
  • Plant the bulbs about 20-30cm (8-12") apart. For impact, plant in groups.
  • Alliums work well in rockeries and crowded gardens as they don't take up much space.
  • Add horticultural grit to heavy soil to improve water drainage. 
  • The Allium bulbs need to be planted pointy end up.
  • Water the bulb well once in situ.
  • To help the soil drain well it is also beneficial to spread mulch, wood chips and organic matter over the entire planting area.
  • Alliums will flower around May/June.
  • Cut the Alliums back at the end of their blooming season. They will then continue to grow in your garden year on year with very little maintenance.

Planting Alliums in Pots 

  • Plant Alliums the same depth for pots as in the garden. Plant three times the diameter of the bulb. For example, if the bulb is 5cm (2") in size then it needs to be planted 15cm (6") deep.
  • For a garden with limited space, you may want to produce a fuller display of spring flowers by layering your bulbs like a lasagne. Simply plant your bulbs deeper to start with, with the largest or latest flowering bulbs further down, moving to the smallest and earliest flowering in the top layer. The shoots from the lower bulbs will find their way around the other bulbs. If you are planting the Alliums first, allow 10cm (4") of soil underneath the bulbs.
  • Add horticultural grit to heavy soil to improve water drainage. 
  • The Allium bulbs need to be planted pointy end up.
  • Water the bulb well once in situ.
  • To help the soil drain well it is also beneficial to spread mulch, wood chips and organic matter over the entire planting area.
  • Alliums will flower around May/June.
  • Cut the Alliums back at the end of their blooming season. They will then continue to grow in your garden year on year with very little maintenance.

Care Instructions

How to care for Alliums

  • Add a potash feed to enhance growth and strengthen the bulbs for flowering year after year.
  • Allow flower to die back and remove any dead foliage in early Summer.
  • Remove any dead stems that become detached from their bases.
  • Alliums are hardy and can therefore be left in the ground all year round.
  • Keep an eye out for any diseased foliage.
  • Seldom need support.
£6.00

Allium Giganteum

Ornamental Onions
  • 1 Bulb £6.00
  • 3 Bulbs £15.00
  • 6 Bulbs £25.00
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Flowering Period: May/June

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Specification
Also known as: Ornamental Onions
Colours: Bright Purple
Aspect: Full Sun with well-drained soil
Height: 120-150 cm / 48-59"
Planting period: Autumn
Soil Type: Fertile, well drained
Bulb Size: 24cm+
Hardiness: Hardy
Shipping est: Dispatched from Sept 2024 onwards
Delivery period: Autumn delivery (Sept to Nov 2024)
Suitable for containers: Yes
Scented: Unscented
Double flowered: No
Border Position: Middle/Back
SKU harts11091
  • Description
    Allium Giganteum is one of the tallest varieties of alliums as it will reach up to 1.5m tall, with its spectacular ball-shaped blooms made up of masses of tiny bright Purple flowers that will reach 20cm in diameter.
     
    To get the best from your Alliums, we suggest planting them in groups along the back of your borders or on their own interspersed between your other flowers and plants. Once planted in the autumn, they will not disappoint once they flower in late spring. 
     
    These majestic beauties really are fast becoming all an round favourite amongst the gardening community, new and old! 
  • Additional Information
  • Reviews (1)
  • Delivery / Returns
  • Planting & Growing Instructions

    How to plant Alliums

    • Plant Alliums in the Autumn for Spring flowering.
    • Choose a location to plant your Allium Bulbs, they like to be in full sunlight and well-drained soil.

    Planting Alliums in the Garden

    • Once you have found the perfect spot in your garden to grow your Alliums, you need to dig holes in the flower bed that are three times the diameter of the bulb. For example, if the bulb is 5cm (2") in size then it needs to be planted 15cm (6") deep.
    • Plant the bulbs about 20-30cm (8-12") apart. For impact, plant in groups.
    • Alliums work well in rockeries and crowded gardens as they don't take up much space.
    • Add horticultural grit to heavy soil to improve water drainage. 
    • The Allium bulbs need to be planted pointy end up.
    • Water the bulb well once in situ.
    • To help the soil drain well it is also beneficial to spread mulch, wood chips and organic matter over the entire planting area.
    • Alliums will flower around May/June.
    • Cut the Alliums back at the end of their blooming season. They will then continue to grow in your garden year on year with very little maintenance.

    Planting Alliums in Pots 

    • Plant Alliums the same depth for pots as in the garden. Plant three times the diameter of the bulb. For example, if the bulb is 5cm (2") in size then it needs to be planted 15cm (6") deep.
    • For a garden with limited space, you may want to produce a fuller display of spring flowers by layering your bulbs like a lasagne. Simply plant your bulbs deeper to start with, with the largest or latest flowering bulbs further down, moving to the smallest and earliest flowering in the top layer. The shoots from the lower bulbs will find their way around the other bulbs. If you are planting the Alliums first, allow 10cm (4") of soil underneath the bulbs.
    • Add horticultural grit to heavy soil to improve water drainage. 
    • The Allium bulbs need to be planted pointy end up.
    • Water the bulb well once in situ.
    • To help the soil drain well it is also beneficial to spread mulch, wood chips and organic matter over the entire planting area.
    • Alliums will flower around May/June.
    • Cut the Alliums back at the end of their blooming season. They will then continue to grow in your garden year on year with very little maintenance.
  • Care Instructions
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