Sam Hopkins Dahlia Tubers

• Variety: Sam Hopkins
• Type: Waterlily
• Colour: Deep maroon to near-black, velvety
• Flower size: 10 to 15cm across
• Height: 100cm
• Spread: 60cm
• Flowering: July to November
• Cutting: Yes. Dramatic dark stems, striking in arrangements
• RHS AGM: No
• Sold as: Single tubers, hand-graded, Dutch first-class quality
• Plant outdoors: March to July, when soil reaches 15°C (typically May in most of the UK)
• Delivered: From March. Collection from Castle Cary also available

Sam Hopkins: A Dark Waterlily Dahlia That Looks Like Velvet

Waterlily dahlias have a shallow, open form, with broad flat petals that overlap like a lily floating on water. Most are pale. Sam Hopkins breaks the rule. The flowers are deep maroon, so dark they verge on black, with a velvety texture that absorbs light. It's a dramatic combination: the elegant, understated waterlily shape carrying a colour that demands attention.

At 10 to 15cm across on a 100cm plant, the flowers are mid-sized and the habit is manageable. The stems are dark and sturdy. It does need staking because the flat waterlily form catches rainwater, making the heads heavier than they look. In a sheltered spot, a light ring support is usually enough.

As a cut flower, Sam Hopkins is striking. The deep maroon against a clean white vase, or mixed with pale dahlias in a dark-and-light arrangement, makes an immediate impression. The waterlily form sits flat and open in a vase, quite different from the rounded profile of a ball or decorative.

Sam Hopkins in the Border

Dark flowers need contrast, and the flat waterlily shape needs something more structured alongside it. Plant Sam Hopkins with the pure white of Cafe au Lait Supreme (white dinnerplate) for a high-drama dark-and-light pairing. The tight globes of Golden Sceptre (bright yellow ball, 90cm) provide a warm contrast and a completely different form. Gerrie Hoek (shell pink waterlily, same type but much paler) gives you a waterlily gradient from light to dark. Silver-foliaged plants like Artemisia or Stachys keep the dark flowers from disappearing into the border.

Why Ashridge?

Our dahlia tubers are Dutch first-class quality, imported direct and hand-graded by us. We discard undersized tubers so you get a clump with viable eyes, ready to grow. Delivered by next-day courier from March, with our one-year plant guarantee, Feefo Platinum Service Award, and human support from the team in Somerset if anything isn't right. Browse our waterlily dahlia range or the complete dahlia collection.

Frequently Asked Questions

What's a waterlily dahlia?

A dahlia with broad, flat petals that overlap in a shallow, open form, resembling a waterlily floating on a pond. The blooms are flatter and less structured than decorative or ball types. It's one of the more elegant dahlia forms, typically used in borders and arrangements where you want a calmer, less busy flower shape. Our dahlia types guide explains all the classifications.

Is Sam Hopkins really black?

Close. In direct sunlight the deep maroon shows through, but in shade or evening light the flowers read as near-black. The velvety petal texture absorbs light rather than reflecting it, which deepens the impression. For comparison, Dark Spirit (decorative form) is similarly dark but in a spherical shape. Rip City (semi-cactus) is dark with spiky form. Sam Hopkins is the only near-black waterlily in our range.

Does Sam Hopkins handle rain?

Not brilliantly. Waterlily dahlias have flat, open flowers that hold rainwater, and the weight can snap stems. Stake well and grow in a sheltered spot if you can. Picking open flowers before forecast rain is the practical solution: the plant will produce more. Ball and cactus types handle rain much better.

Will Sam Hopkins grow in a pot?

At 100cm it's borderline. A large pot (at least 35cm across and deep), good staking, and shelter from wind will make it work, but it's happier in a border. For a dark dahlia that's more container-friendly, Dark Spirit at 90cm is a better fit. Our pots guide covers the options.

How long does Sam Hopkins last in a vase?

Waterlily dahlias generally have a shorter vase life than ball or cactus types because the open, flat petals dry out faster. Expect three to five days. Cut fully open flowers in the morning, condition stems in hot water for an hour, and keep the vase topped up. The dark colour doesn't show wilting as obviously as pale varieties, which is a practical advantage. Full growing advice in our dahlia growing guide.