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How to Grow Diascia

Diascia barberae

Half Hardy Warm Season

When to Start

Sow indoors 7 weeks before last frost, or direct sow outdoors after frost risk has passed and soil reaches 10°C.

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Growth Stages

Sow seeds
Germination ~12d
Flowering ~90d

Approximate days from start

Care Essentials

  • Balanced liquid feed every two weeks. Avoid overfeeding — diascia prefers lean conditions and flowers better without excess nitrogen.
  • Dainty trailing plant with masses of small twin-spurred flowers in pink, coral, or white. Prefers cooler conditions than most bedding — thrives in UK summers. Flowers best in spring and autumn, may pause in extreme heat. Excellent for baskets and window boxes.

Companion Planting

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Growing Conditions

Min. soil temperature: 10°C+

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Spacing & Planting

Plant spacing 20 cm
Row spacing 25 cm
Mature height 25 cm
Mature spread 30 cm

For trailing varieties in hanging baskets and containers. Creates a delicate cascade of flowers at this spacing.

Try our spacing calculator →

Care Guide

Feeding
Balanced liquid feed every two weeks. Avoid overfeeding — diascia prefers lean conditions and flowers better without excess nitrogen.
Watch for
  • Slugs on young plants
  • Generally pest-free
  • Dislikes extreme heat

Pests & Diseases

Pest Slugs and Snails

Identification: Irregular holes in young leaves, slime trails, seedlings eaten overnight

Organic treatment:
  • Beer traps
  • Copper tape around containers
  • Evening hand-picking
Chemical treatment:
  • Ferric phosphate pellets (wildlife-safe)
Disease Root Rot Pythium spp.

Symptoms: Wilting despite moist soil, brown mushy roots, plant collapse from the base

Treatment: Remove affected plants. Improve drainage. Allow compost to dry slightly between waterings.

Prevention: Use free-draining compost. Never let pots sit in water. Ensure drainage holes are clear.

Growing Conditions

Min. soil temperature10°C
Base growth temperature8°C
Min. daylength to start11h
Photoperiod sensitivityday neutral

Frequently Asked Questions

How far apart should I plant Diascia?
Plant Diascia 20cm apart with 25cm between rows.
When does Diascia flower?
Diascia typically flowers approximately 45 days after transplanting.
Is Diascia frost hardy?
Diascia is classified as Half Hardy.

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