We have found 70 plants that meet your criteria.

Allium Purple Sensation ‘Allium hollandicum Purple Sensation’ Rich, deep purple globes £3.50 Buy
Allium cristophii ‘Allium cristophii’ Huge globes of star-like, lilac flowers £5.00 Buy
Allium Globemaster ‘Allium Globemaster’ Enormous, deep violet globes £5.00 Buy
Allium Schubertii ‘Allium schubertii’ The flowers look like giant fireworks £7.50 Buy
Round-headed Leek ‘Allium Sphaerocephalon’ Small, wine-coloured flowers on tall stems £4.00 Buy
Allium unifolium ‘Allium unifolium’ A longer flowering period that most Alliums £3.75 Buy
Single Late Tulip ‘Tulia El Nino’ Probably our tallest tulip £4.00 Buy
Triumph Tulip ‘Tulipa Abu Hassan’ As exotic looking as the name suggests £3.50 Buy
Species Tulip ‘Tulipa acuminata’ Strange, spidery blooms in April £9.00 Buy
Single Late Tulip ‘Tulipa Andre Rieu’ One of the last tulips to flower £4.00 Buy
Double Late Tulip ‘Tulipa Angélique’ One of the best 'double lates' £4.00 Buy
Double Late Tulip ‘Tulipa Antraciet’ Massive paeonia-like flowers £3.00 Buy
Triumph Tulip ‘Tulipa Arabian Mystery’ Sumptuous bi-coloured blooms £5.00 Buy
Viridiflora Tulip ‘Tulipa Artist’ Good for adding colour contrast £4.00 Buy
Lily-flowered Tulip ‘Tulipa Ballade’ Listed by the RHS as one of their top 10 tulips £4.00 Buy
Lily-flowered Tulip ‘Tulipa Ballerina’ Scented, orange flowers £3.00 Buy
Triumph Tulip ‘Tulipa Barcelona’ Great for forcing in pots for early flowers £4.00 Buy
Double Late Tulip ‘Tulipa Black Hero’ Almost black double flowers £5.00 Buy
Tulip Black Jewel ‘Tulipa Black Jewel’ A tall, very dark coloured tulip £7.50 Buy
Fringed Tulip ‘Tulipa Blue Heron’ Long-lasting fringed flowers £4.00 Buy