Bacterial Severity: High ⚠️ Contagious

Crown Gall: Urgent! How to Save Your Plant

Crown gall is a bacterial disease caused by Agrobacterium tumefaciens that affects over 140 species of plants. The bacteria insert DNA into plant cells, causing them to divide uncontrollably and form large tumor-like growths (galls) primarily on roots, stems, and at the soil line. These galls restrict water and nutrient flow, severely impacting plant health and potentially killing the plant.

Spread speed

Medium

Recovery time

28 days

🔍 Symptoms

Main Symptoms

! Large, rough, woody tumor-like growths (galls) at the base of stems
! White masses of callus tissue on roots and crown
! Galls appearing at or just below soil line
! Swellings on stems, limbs, trunks, or roots where wounds occur
! Stunted growth due to restricted water and nutrient flow
! Decline in overall plant vigor and health

Visual Signs

Large growths or tumors (galls) forming at base of stemsWhite masses of callus tissue or small swellings on rootsGalls appearing at soil line or just below surfaceSwellings on limbs, trunks, roots, or anywhere wounds occurRough, woody tumorous growthsRestricted water and nutrient flow from roots

Affected parts: RootsStemWhole plant

❓ Possible Causes

→ Infection by Agrobacterium tumefaciens bacteria through wounds
→ Physical damage during planting, grafting, or cultivation
→ Soil insect feeding creating entry wounds
→ Root damage from excavation or mechanical injury
→ Use of contaminated tools or infected nursery stock
→ Bacteria surviving in soil from previous infected plants

💊 Treatment

⚡

Quick Fixes

~14 days

Step 1

Identify and mark all visible galls on crown and roots

Step 2

During dry season, use sterilized sharp knife or pruning saw to cut galls

Step 3

Cut at least 1-2 cm into healthy wood tissue around each gall

Step 4

Remove all gall tissue completely without leaving infected remnants

Step 5

Allow cut surfaces to dry in open air for 24-48 hours

Step 6

Apply copper-based wound dressing to exposed areas

Step 7

Monitor weekly for 4-6 weeks for regrowth

Materials needed:

Sharp pruning shearsHypochlorite solutionPruning sealer pasteCopper-based bactericide

🌿

Organic Treatment

~28 days

Step 1

Inspect plants carefully before purchase and select only certified disease-free stock

Step 2

Dip bare roots or drench potted plants with Agrobacterium radiobacter K-84 (commercial product: Galltrol) before planting

Step 3

Sterilize all pruning tools with 70% alcohol or 10% bleach solution between cuts

Step 4

Apply copper octanoate as a preventive soil drench in high-risk areas

Step 5

Remove small galls by cutting into healthy wood during dry season, minimizing healthy tissue removal

Step 6

Expose cut surfaces to air and sunlight for natural drying

Materials needed:

Sterilized knife or scalpel70% alcoholCinnamon powder pasteWell-aged compostTrichoderma (powder)Garlic extract

🔬

Expert Treatment

~42 days

Step 1

Conduct comprehensive site assessment and test soil for bacterial load

Step 2

Remove and destroy severely infected plants (burn or double-bag for disposal)

Step 3

Soil solarization: cover moist bare soil with clear plastic for 4-6 weeks in sunny season (soil temp 140°F/60°C)

Step 4

Alternatively, steam-sterilize soil at 140°F for 30 minutes or double-tent solarize at 160°F

Step 5

Apply Agrobacterium radiobacter K1026 (second-generation biocontrol strain) to soil and root zones

Step 6

Implement strict quarantine protocol for new plants with 30-day observation period

Step 7

Treat remaining plants with integrated approach: surgical removal + biocontrol + copper treatment

Step 8

Establish 3-meter isolation zone around previous infection sites

Step 9

Monitor with monthly inspections for 12 months

Step 10

Implement preventive biocontrol applications for 2-3 years

Step by Step

1
Inspect plants regularly for gall formation
2
Remove small galls immediately with sterilized cutting tools
3
If galls are extensive, remove and destroy entire plant
4
Do not replant susceptible species in same location for 3-4 years
5
Disinfect all tools and equipment that contacted infected plants
6
Monitor surrounding plants for signs of spread
7
Apply biological control agents to nearby healthy plants as protection

🧪 Solutions

🌱 Natural Solutions

✓ Apply Agrobacterium radiobacter K-84 biological control to bare roots before planting
✓ Drench potted plants with K-84 solution to protect against infection
✓ Remove small galls early by cutting with sterilized tools
✓ Improve soil drainage with organic matter amendments
✓ Apply beneficial microorganisms to outcompete pathogenic bacteria

💉 Chemical Solutions

✓ No effective chemical treatments available for crown gall
✓ Chemical prevention methods are ineffective once infection occurs
✓ Copper-based bactericides show minimal efficacy
✓ Focus on prevention rather than chemical treatment

🛡️ Prevention

✓ Inspect all nursery stock carefully and reject plants with any galls
✓ Sterilize all pruning tools between plants using 10% bleach solution
✓ Avoid wounding plant crowns and roots during cultivation
✓ Control root-chewing insects to prevent wound creation
✓ Improve soil drainage to reduce bacterial activity
✓ Use certified disease-free planting material
✓ Solarize soil with clear plastic for 4-6 weeks before planting
✓ Remove and destroy infected plants immediately - do not compost

🌿 Common in These Plants

Croton

African Milk Tree

Moon Orchid