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Dahlia Decorative Mystery Day (1 Bulb)

£4.99 £11.99

BULB1026

Pack Size: 1 Bulb

1 Bulb

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Product Description

Dahlia Decorative Mystery Day (1 Bulb)

Dahlia 'Mystery Day' bulb Dahlia 'Mystery Day' is a striking, bold variety that brings rich contrast and drama to the garden with its large, bi-coloured blooms. This dahlia features dark, velvety red petals edged in bright white, creating a dazzling display that stands out in borders, beds, and containers. Blooming prolifically from midsummer until the first frost, Dahlia 'Mystery Day' is an excellent choice for adding depth and vibrancy to any garden design. Its eye-catching flowers also make it perfect for cut flower arrangements, bringing a touch of elegance indoors. Hardy in the UK with proper care, this dahlia is a stunning choice for creating standout displays.
The blooms of Dahlia 'Mystery Day' are large, fully double flowers reaching up to 15-20cm in diameter. Each flower head features deep, velvety red petals outlined with a bright white margin, creating a striking bi-colour effect. The petals are broad and gently curved, forming a full, rounded bloom that captures attention. Set against lush green foliage, these dramatic flowers add a touch of sophistication and contrast beautifully with other summer blooms, making them a standout in any garden.
How to Grow
Planting: Plant 'Mystery Day' dahlia tubers in spring after the last frost has passed, in a sunny location with well-drained, fertile soil. Position the tubers about 10-15cm deep, with the “eye” or growth point facing upwards, and space them around 45-60cm apart to give them room to grow.
Watering: Water the tubers well after planting to help them establish. Once shoots appear, water regularly, keeping the soil consistently moist but not waterlogged. Deep watering once or twice a week during dry spells will encourage strong growth and abundant blooms.
Feeding: Use a high-potassium fertiliser, such as tomato feed, every two weeks once flowering begins. Regular feeding will support healthy blooms and keep the plant looking vibrant throughout the flowering season.
Staking: With its large blooms, 'Mystery Day' may need staking, particularly in exposed areas. Insert stakes at planting time to avoid disturbing the tubers later, and tie the stems loosely to support the flowers as they grow.
Deadheading and Maintenance: Regularly deadhead spent blooms to encourage a continuous flush of fresh flowers and a tidy appearance. After the first frost, cut back the foliage, and either lift and store the tubers or cover them with mulch if leaving them in the ground over winter.
Overwintering: In colder regions of the UK, lift and store dahlia tubers after the first frost. Allow them to dry, then store them in a cool, frost-free place in slightly damp compost until replanting in spring. In milder areas, add a layer of mulch for winter protection if leaving them in the ground.
With its bold, bi-colour blooms and long flowering period, Dahlia 'Mystery Day' adds dramatic beauty and charm to UK gardens, providing vibrant displays from summer to autumn. This dahlia’s eye-catching flowers make it a perfect choice for both garden enjoyment and indoor arrangements, creating a sense of luxury and elegance in any setting.
Pack contains 1 bulb

Specs & Details

Established height: 90-120cm
Established spread: 30-60cm
Plant spacing: 6 bulbs per m²
Flower colour: Purple
Life cycle: Annual
Habit: Bushy

Features

Thrives Full Sun

Plant Calendar

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FAQs

Please read our FAQs page to find out more.

When can I plant dahlia tubers in the UK?

Dahlia tubers can be started indoors in spring, then planted outside once the risk of frost has passed. In most parts of the UK this is usually from late May, while colder areas may need to wait until early June. If you are searching for dahlia tubers ready to plant, they can also be planted directly into the ground from mid to late April, although growth will be slower until the weather warms up. Dahlias are tender plants, so new shoots must be protected from frost.

Why have my dahlia tubers not sprouted or grown?

Dahlia tubers can be slow to sprout, particularly in cool conditions. They need warmth, good light and only lightly moist compost while they are starting into growth. Cold, wet compost is one of the most common reasons a dahlia tuber fails, as overwatering can quickly cause rot before shoots appear. Check that the old stem or growing point is facing upwards and sits just below the compost surface. Some tubers take longer than others, so give them time before assuming they will not grow.

Are dry or broken dahlia tubers still okay to plant?

Dahlia tubers can look wrinkled or slightly dry while dormant, particularly after delivery. They can still grow if they remain firm and are attached to a section containing a viable growing point, often known as the crown or old stem area. A tuber that has broken away without any crown tissue is unlikely to produce shoots on its own. Do not plant tubers that are soft, wet, badly mouldy or hollow, as these are signs of rot or serious deterioration.

Will my dahlias flower in the colour shown on the product page?

Dahlia tubers should produce flowers in the colour and form described on the product page. Natural flowers can look slightly different in shade depending on sunlight, weather and soil conditions, while product images can also appear brighter or darker across different screens. Dahlias flower from summer into autumn, often continuing until the first frosts. A sunny position, regular watering during dry weather and removing faded blooms will help plants produce the strongest display.

Are dahlias hardy, and will they come back next year?

Dahlias are not fully hardy in most of the UK and will not tolerate frost. After the first frost has blackened the foliage, cut the stems back and lift the tubers to store somewhere dry and frost-free over winter. They can then be replanted the following spring. In very mild areas, some gardeners leave tubers in the ground under a thick mulch, but lifting them is the safer option, particularly in colder or wetter areas.