Thompson & Morgan

Important delivery notice
The products on this site are only delivered to UK addresses. If you require delivery to another country please visit one of our other sites below.

Refine Results

Refine by..

Email Newsletter

Sign up to our newsletter

Perennial & Biennial Seeds


Biennials live for 2 years, whereas perennials live for longer. As a general rule, biennial and perennial seeds should be sown in spring, but some can be sown in autumn as well. Many varieties will self-seed after flowering, giving you even more plants!

We have found 42 products.
 
Commelina Dianthifolia

Commelina dianthifolia

Bird-bill Day Flower, Widow's Tears

  Customer Rating

A very rare plant indeed. This is one of the few plants with such intense blue flowers and that will also perform well in the garden. Flowering in its first year with 2.5cm (1in) gentian blue flowers, it then produces tubers and springs back to life the following year with an unceasing display of blooms. Wonderful in containers, rock gardens and the border (regardless of soil conditions). Hardy down to -8/-10C. Flowers summer. Height 15-30cm (6-12in.)

 More info
    • 1 packet (25 seeds)

    • Despatch: Within 2 Days
    •  
    • £1.49
Geranium Wallichianum Buxtons Blue

Geranium wallichianum 'Buxton's Blue'

Geranium wallichianum 'Buxton's Variety', Hardy Geranium, Cranesbill
This is definitely the star of the perennial geranium family producing flowers virtually non-stop from mid summer to early autumn. The flowers themselves are a delight, a gorgeous clear opal, or Nemophila blue with large white centres, against which the dark stamens and dark veining of the petals contrast beautifully. The plant forms an attractive clump with attractive wedge shaped, silky, deeply toothed leaves, making this a very garden worthy plant even when not in flower. It comes quite true from seed and has been given an Award of Garden Merit by the Royal Horticultural Society. Requirements: One of the easiest perennials to cultivate, happy in sun or light shade and any free draining garden soil. More info
    • 1 packet (8 seeds)

    • Despatch:
    •  
    • £1.49
    • Out of stock
Nepeta Transcaucasica* Blue Infinity

Nepeta transcaucasica 'Blue Infinity'

Catmint

Tall wands of violet-blue flowers in seemingly infinate quantity over a long period. With its characteristic aromatic fragrance it is extremely effective in the border, long-lived, easily grown and very reliable.

* Seed came to T&M under this name which is yet to be verified.

 More info
    • 1 packet (45 seeds)

    • Despatch: Within 2 Days
    • SAVE £3.30  
    • £3.99 £0.69
Meconopsis Grandis

Meconopsis grandis

Himalayan Blue Poppy
 Customer Rating

Sturdy and long-lived with huge flowers 10-12cm (4-5in) across in a wonderful blue, shot with violet on erect stems.

 More info
    • 1 packet (30 seeds)

    • Despatch: Within 2 Days
    •  
    • £2.99
Delphinium Grandiflorum Summer Nights

Delphinium grandiflorum 'Summer Nights'

Delphinium chinense

Attractive dwarf plants covered in a blanket of dainty midnight-blue flowers. Flowering in their first year from sowing makes them perfect for bedding borders or containers, providing a colourful display over a long summer period.

 More info
    • 1 packet (20 seeds)

    • Despatch: Within 2 Days
    •  
    • £0.69
Geranium Pratense Striatum Splish Splash™

Geranium pratense 'Splish Splash™'

Geranium pratense 'Striatum', Hardy Geranium, Meadow Cranesbill

One of the most beautiful, striking and unusual Perennial Geraniums with mauve-blue splashes and flecks on pure white petals, each 3cm (¼in) flower head appearing to be individually designed and painted. A fascinating, rare and prized border plant, coming remarkably true from seed. Flowers summer. Height: 45-75cm (18-30in).

 More info
    • 1 packet (8 seeds)

    • Despatch:
    •  
    • £0.99
    • Out of stock
Primula X Tommasinii You & Me Blue

Primula x tommasinii 'You and Me Blue'

Hose-in-Hose Primula, Polyanthus

 A rarely-offered Primula with the amazing feature of producing two layers of flowers per stem. This unique flower form was first recorded in 1597 and was known as 'Hose in Hose' types after the way Elizabethan gentlemen wore their stockings! You & Me Blue is a delightful selection, which shows off this intriguing characteristic at its best, as well as displaying excellent garden performance and winter hardiness in borders or containers. Height: 15-20cm (6-8in). More info
    • 1 packet (12 seeds)

    • Despatch: Within 2 Days
    •  
    • £1.69
Agapanthus Headbourne Hybrids

Agapanthus 'Headbourne Hybrids'

African Blue Lily

 Free flowering with large round heads of true blue flowers growing into a thick established clump. Truly hardy. Bold, attractive bulbous plants for sheltered borders, tubs, containers etc. Elegant strap shaped leaves and bunches of blue flowers on 2-3ft long sterns. The dried seed head can be used for winter decoration. There is considerable evidence that these hybrids are really hardy in many parts of the British Isles, particularly where good drainage is possible. They flower freely in their second year and generally make very good garden plants, growing into a thick established clump. Flowers mid/late summer. More info
    • 1 packet (22 seeds)

    • Despatch: Within 2 Days
    •  
    • £3.79
Amsonia Tabernaemontana

Amsonia tabernaemontana

Rhazya, Eastern Bluestar
Starry clusters of elegant pale blue Amsonia flowers appear from spring to midsummer. This rarely seen perennial deserves better recognition in gardens for its long flowering period and reliable performance year after year. Amsonia tabernaemontana grows happily in sun or dappled shade and copes well with drought. An attractive and unusual addition to garden borders and woodland gardens. Height: 90cm (35"). Spread: 45cm (18"). More info
    • 1 packet (30 seeds)

    • Despatch: Within 2 Days
    •  
    • £0.69
Delphinium X Cultorum Tall Black Knight

Delphinium x cultorum 'Tall Black Knight'

Tall, robust, candle-like flower spikes packing with attractive, deep blue blooms, each complemented by a striking large black bee in the centre. A stunning addition to any border. Height: 120-150cm (4-5ft). More info
    • 1 packet (100 seeds)

    • Despatch: Within 2 Days
    •  
    • £2.79
Aquilegia Caerulea

Aquilegia caerulea

Rocky Mountain Columbine, Colarado Blue Columbine, Granny's Bonnet
Possibly the most beautiful Aquilegia of all. With glorious light to deep blue flowers 2-3in across sometimes fetching bi-coloured with white. An excellent border perennial, grand for cutting, in bloom for several weeks and will grow in sun or light shade. Flowers late spring/early summer. Height: 30-35cm (12-14in) More info
    • 1 packet (100 seeds)

    • Despatch: Within 2 Days
    •  
    • £2.99
Meconopsis Betonicifolia

Meconopsis betonicifolia

Himalayan Blue Poppy, Tibetan Blue Poppy
 Customer Rating
Is there a more beautiful bloom in the entire flower kingdom then the famous Blue Poppy? It is only to be expected that an elusive, magical flower like this is a little harder to grow. The secret with this plant is to grow cool and well shaded. Height: 60-90cm (24-36in). More info
    • 1 packet (50 seeds)

    • Despatch: Within 2 Days
    •  
    • £2.99