Skip to content

How to Grow Celosia

Celosia argentea

Tender Warm Season

When to Start

Start seeds indoors 6 weeks before your last frost date. Transplant outdoors once night temperatures stay above 12°C and soil has warmed to at least 15°C.

Don't know your frost date? Find it here →

Growth Stages

Sow seeds
Germination ~10d
Flowering ~80d

Approximate days from start

Care Essentials

  • Feed with a balanced liquid fertiliser every two weeks once plants are established in their final position. Avoid high-nitrogen feeds which promote leafy growth at the expense of flowers.
  • Celosia covers two distinct forms — plumosa (feathery plumes) and cristata (brain-like cockscomb). Both are tender annuals that demand warmth. Do not let seedlings get cold or root-bound, as this triggers premature flowering before plants are large enough to perform well.

Companion Planting

Growing Conditions

Min. soil temperature: 15°C+
Germination temperature: 20–25°C

Get a personalized schedule for Celosia based on your exact frost dates

Start planning free

Enter your last frost date to see your dates

Don't know your frost date? Find it here

Spacing & Planting

Plant spacing 20 cm
Row spacing 30 cm
Sow depth 0 cm
Mature height 40 cm
Mature spread 25 cm

Covers both plumosa (feathery plumes) and cristata (cockscomb) types. Plant out only after all frost risk has passed. Closer spacing can increase humidity — ensure good airflow.

Try our spacing calculator →

Care Guide

Feeding
Feed with a balanced liquid fertiliser every two weeks once plants are established in their final position. Avoid high-nitrogen feeds which promote leafy growth at the expense of flowers.
Watch for
  • Aphids
  • Spider mites
  • Stem rot
  • Leaf spot
  • Damping off

Pests & Diseases

Pest Aphids

Identification: Clusters of small soft-bodied insects on shoot tips and flower buds, causing distorted growth and sticky honeydew deposits

Organic treatment:
  • Blast off with a strong jet of water
  • Spray with fatty acid-based insecticide
  • Encourage ladybirds, lacewings and hoverflies
Chemical treatment:
  • Spray with a contact insecticide containing deltamethrin or lambda-cyhalothrin
Pest Spider Mites

Identification: Fine webbing on leaves and stems, with tiny pale speckling on leaf surfaces; worst in hot, dry conditions

Organic treatment:
  • Increase humidity around plants by misting
  • Spray with insecticidal soap or neem oil
  • Remove heavily infested leaves
Chemical treatment:
  • Apply a miticide labelled for ornamental plants
Disease Stem Rot

Symptoms: Soft, discoloured stem base, wilting despite moist soil, plant collapse

Treatment: Remove and destroy affected plants immediately. Improve drainage and avoid overwatering

Prevention: Ensure well-drained soil, avoid waterlogging, and do not plant out in cold wet conditions

Disease Leaf Spot

Symptoms: Brown or tan spots with darker borders on leaves, sometimes with yellowing around the spots

Treatment: Remove affected leaves. Improve airflow around plants. Apply a copper-based fungicide if severe

Prevention: Space plants well, avoid overhead watering, and remove plant debris at the end of the season

Disease Damping Off

Symptoms: Seedlings collapse at soil level with a pinched, water-soaked stem base

Treatment: Remove affected seedlings immediately. Improve ventilation and reduce watering

Prevention: Use fresh sterile compost, avoid overwatering, ensure good airflow around seedlings, and do not sow too densely

Growing Conditions

Min. soil temperature15°C
Germination temperature20–25°C
Base growth temperature12°C
Min. daylength to start12h
Photoperiod sensitivityday neutral

Frequently Asked Questions

How far apart should I plant Celosia?
Plant Celosia 20cm apart with 30cm between rows.
When does Celosia flower?
Celosia typically flowers approximately 65 days after transplanting.
Is Celosia frost hardy?
Celosia is classified as Tender.

Calculate your harvest date →

Plan Celosia in your garden — get personalized frost-date scheduling

Start planning free