Dahlia 'Arabian Night'
Dahlia 'Arabian Night'. Family Asteraceae. Bulb.
Also called 'Arabian Night' decorative dahlia.
Dahlia 'Arabian Night' is a tuberous perennial grown for fully double, deep burgundy-red flowers that can look almost black in subdued light. It flowers from summer until frost and makes a useful border and cutting-garden plant. In cold climates it is often grown as an annual, or its tubers are lifted and stored indoors for winter.
At a glance
- Sun
- Full sun, ideally at least 6 hours daily; light afternoon shade can help in very hot climates.
- Water
- Keep evenly moist during active growth, watering deeply when the surface soil begins to dry. Avoid waterlogged soil, especially before shoots emerge and during winter dormancy.
- Soil
- Fertile, well-drained soil enriched with compost; slightly acidic to neutral soil is ideal.
- Height
- 3-4 ft (0.9-1.2 m)
- Spread
- 1.5-2 ft (0.45-0.6 m)
- Flowers
- Summer to the first autumn frost; fully double, deep burgundy-red flowers, usually about 4-6 in (10-15 cm) across.
- Foliage
- Green, divided leaves with toothed leaflets on upright, branching stems; foliage dies back with frost.
- Growth
- Fast; reaches flowering size in one growing season.
- Care needed
- High
The year at a glance
- Heat tolerant
- Low allergen
| J | F | M | A | M | J | J | A | S | O | N | D | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Flowers | ||||||||||||
| Plant |
Northern hemisphere months. In Australia, shift them by six.
- Difficulty
- Hard
- Toughness
- Needs looking after
Will it suit your garden?
Pick your zone, country, light and whether you have pets.
Full sun is 6 or more hours of direct sun a day, part shade 3 to 6 hours, shade under 3.
How it grows
Planting day
0.5 ft (0.15 m)
After 1 year
3 ft (1.1 m)
full size
Full size in one season.
From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.
Good to know
- Cats and dogs
- Mildly toxic: may upset a stomach
- Growth rate
- Fast
Care
Jobs through the year
- WaterMay–Jun, every 7 days
- Once shoots emerge, water deeply if the surface dries; avoid soaking unsprouted tubers.
- WaterJul–Aug, every 4 days
- Keep established plants evenly moist; skip after soaking rain and water more often in heat.
- WaterSep–Oct, every 7 days
- Water during dry spells while growing; stop as frost kills the foliage.
- FeedJun–Sep, every 28 days
- Feed established growth with a balanced flowering fertilizer at label rates; avoid excess nitrogen.
- MulchJun
- Mulch once soil warms, keeping material away from stems.
- PruneJun
- Pinch the growing tip at 30–40 cm tall to encourage branching.
- ProtectMay–Oct, every 7 days
- Stake at planting, check stem ties and protect emerging shoots from slugs.
- DeadheadJul–Oct, every 7 days
- Remove spent flowers back to a strong leaf joint.
- PruneOct–Nov
- After frost blackens the foliage, cut stems down before lifting.
- ProtectOct–Nov
- Lift after the first killing frost, surface-dry and store cool and frost-free in barely moist packing.
- ProtectJan–Apr, Dec, every 30 days
- Inspect stored tubers; discard rot and lightly moisten packing only if tubers shrivel.
- Plant after frost danger has passed and the soil has warmed, with the tuber crown about 4-6 in (10-15 cm) below the surface.
- Install a sturdy stake at planting and tie stems loosely as they grow.
- Water deeply during dry spells; avoid heavy watering of newly planted tubers before growth appears.
- Feed with a balanced fertiliser once growth is established, following the label; avoid excessive nitrogen.
- Mulch once the soil is warm, keeping mulch clear of the stems.
- In cold or winter-wet areas, lift tubers after frost blackens the foliage and store them cool, frost-free and barely moist.
Pruning. Pinch out the growing tip when the plant is about 12-16 in (30-40 cm) tall to encourage branching, and remove spent flowers back to a strong leaf joint throughout summer. After frost blackens the foliage, cut stems down before lifting, or cut back and mulch plants left in suitable ground.
Through the year
- Early spring
- Check stored tubers for rot or shrivelling; pot up sound tubers indoors if you want an earlier start.
- Late spring
- After the last frost, harden off indoor-grown plants, plant outside and install stakes.
- Early summer
- Pinch young plants, tie in new stems and begin regular watering and feeding.
- Summer
- Deadhead frequently, check ties and inspect young growth for slugs and aphids.
- Autumn
- Continue deadheading until frost or the end of flowering; reduce watering as growth dies back.
- Late autumn
- Lift and store tubers where winters are cold or wet; in mild, well-drained gardens, protect dormant crowns with a thick mulch.
- Winter
- Inspect stored tubers periodically, removing rotten material and keeping them frost-free.
In the garden
- Plant in the middle of a sunny border, where neighbouring plants can conceal the lower stems.
- Pair with orange flowers and bronze foliage for a strong late-summer colour contrast.
- Combine with pale pink or white flowers to make the dark blooms stand out.
- Grow in a cutting bed for long-stemmed flowers through summer and autumn.
- Use in a large container with a firm support and regular watering.
Garden styles it suits: Cottage garden, English country, Romantic rose garden, Hot border, Autumn colour and Potager (kitchen garden).
Plant it with: Purpletop vervain, Salvia, Cosmos, Crocosmia, Fountain grass and Zinnia.
Wildlife: The densely double flowers provide little accessible pollen or nectar compared with single-flowered dahlias. Foliage can shelter small garden invertebrates.
Problems to watch for
- Slugs and snails can destroy emerging shoots: inspect at dusk, remove hiding places and use an appropriate labelled control if needed.
- Aphids cluster on soft growth: wash them off with water or use insecticidal soap according to the label.
- Powdery mildew affects crowded or drought-stressed plants: improve airflow, water the root zone consistently and remove badly affected leaves.
- Tubers rot in wet soil or damp storage: improve drainage, let lifted tubers surface-dry before storage and discard soft, rotten material.
Safety
Dahlias are mildly toxic to cats and dogs if chewed, with foliage and other plant parts potentially causing stomach upset; contact can also cause mild skin irritation. Toxicity to horses or people is not well established, so do not assume the tubers or flowers are edible; wear gloves if the sap irritates your skin.
Easily confused with
Dahlia 'Karma Choc' (Dahlia 'Karma Choc')
Also has very dark red double flowers, but typically has conspicuously dark bronze-purple foliage; 'Arabian Night' normally has green leaves.
Dahlia 'Bishop of Llandaff' (Dahlia 'Bishop of Llandaff')
Has brighter scarlet, semi-double flowers with visible central discs and dark foliage, rather than the fully double burgundy flowers and green foliage of 'Arabian Night'.
The name
The genus Dahlia honours the Swedish botanist Anders Dahl.
Propagation. Divide tuber clumps in spring, giving each division a piece of crown with at least one visible eye; a detached tuber without crown tissue will not grow. Basal cuttings also preserve the cultivar. Seedlings will not reliably match 'Arabian Night'.
Checked against open data
- Accepted botanical name
- Dahlia
Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.
See it in your own yard.
Upload a photo of your yard and see it redesigned with plants that suit your climate, each checked against your zone.