Dahlia Deep Impact

Dahlia ‘Deep Impact’ is a gorgeous, uplifting variety with a beautifully soft, modern colour palette. The blooms have a dreamy ombré effect, blending through pale peach-apricot tones into soft buttery yellow, creating a warm, glowing look that suits almost any border. It’s perfect for mixing with pastels, whites and silvery foliage, and it also works brilliantly as a “bridge” colour alongside brighter dahlias and summer perennials.

Flowering from midsummer right up until the first frosts, ‘Deep Impact’ is also a fantastic cut flower—those sunset shades look stunning in vases. Keep deadheading (or picking regularly) and the plant will keep producing fresh blooms for months.

Planting Instructions

When to Plant:

Plant Dahlia tubers in spring. For the earliest flowers, start tubers in pots indoors from March to April, then plant out once the risk of frost has passed. If planting directly outside, wait until late spring when the soil has warmed.

Where to Plant:
Choose a sunny, sheltered position with fertile, well-drained soil. Dahlias are ideal for mixed borders, cutting gardens and patio containers. They love warmth and perform best in full sun.

How to Plant:

• Depth: Plant tubers about 10–15 cm (4–6 inches) deep, with the old stem (or growing point) facing upwards.
• Spacing: Space plants 45–60 cm (18–24 inches) apart, depending on the final size.
• Soil Prep: Enrich the planting area with well-rotted compost or manure. In heavy soil, improve drainage with grit.

Watering:
Water after planting. Once shoots appear and growth is underway, keep soil evenly moist, especially in dry spells. Avoid waterlogging. Container-grown Dahlias may need watering daily in hot weather.

Aftercare Tips:

• Pinch out the growing tip once plants are around 30 cm tall to encourage bushier growth and more flowers.
• Stake taller stems if needed, especially in exposed borders.
• Deadhead regularly to keep plants flowering until autumn.
• After the first frost blackens the foliage, lift tubers and store dry and frost-free over winter, or protect in the ground with a thick mulch in milder areas.

Top Tip:
Dark foliage Dahlias look incredible in containers—try ‘Deep Impact’ with silver or lime-green companions for a really striking contrast and a modern summer display.

Plant Details

Flowering Period:

July - October (until first frosts)

Height:
24–36" (60–90cm) (approx. depending on conditions)

Position:
Full sun

Tender Perennial:
Overwinter tubers frost-free in the UK