Gardening and Orchardry

Tomato Diseases: Common Pests and How to Combat Them

Author: MozaicNook
Tomato Diseases: Common Pests and How to Combat Them

Grown in gardens and kitchens around the world, tomatoes are a favorite among many people. However, this also makes them susceptible to various diseases and pests. Knowing what these are can help you grow healthy and abundant harvests. In this post we will present some of the most common tomato diseases as well as offer tips on prevention and treatment.

Frequent Tomato Ailments:

1. Early Blight

Symptoms

Dark concentric rings on leaves, stems, or fruits characterize early blight. It generally starts lower down the plant and moves up.

Cause

Alternaria solani fungus.

Prevention and Control:

  • Rotate crops; don’t plant tomatoes in the same spot every year.
  • Water from below to keep foliage dry.
  • Remove infected parts of plants – dispose elsewhere!
  • Use fungicides if necessary or neem oil.

2. Late blight & Tuber Rot Diseases

Symptoms

Large greasy looking dark spots appear on leaves stems and fruit; under humid conditions white mold may develop on underside of leaf surface

Cause

Oomycosis Phytophthora infestans fungus

Prevention & Treatment:

  • Plant disease resistant varieties 
  • Remove immediately destroy infected plants
  • Use fungicides or neem oil as preventative measure

3. Septoria Leaf Spot Disease

Symptoms

Small circular spots with gray centers surrounded by dark borders appear on lower leaves causing them to turn yellowish brown eventually dropping off prematurely giving it a characteristic defoliation pattern

Cause

Septoria lycopersici fungus

Prevention/Control:

  • Rotate crops practicing good garden hygiene 
  • Remove affected leaves from plant 
  • Fungicides should be used where necessary to control spread

4. Verticillium Wilt Disease

Symptoms

Yellowing wilting starting from bottom moving upwards brown spots may appear inside stem

Cause

Verticillium dahliae soil borne fungus

Prevention/Control:

  • Use resistant tomato varieties
  • Crop rotation 
  • Improve soil drainage

5. Fusarium Wilt Disease

Symptoms

Similar to verticillium wilt yellowing wilting of leaves but with fusarium one side usually wilts first

Cause

Fusarium oxysporum fungus

Prevention & Treatment:

  • Plant resistant varieties.
  • Alternate crops and avoid planting tomatoes in the same soil year after year
  • Solarize the soil to reduce fungal populations

Pests That Commonly Attack Tomato Plants

1. Tomato Hornworms

Symptoms:
Huge green caterpillars with white stripes that can defoliate a tomato plant in days. Look out for eaten leaves and droppings.

Prevent & Treat: 

  • Handpick hornworms off the plants and destroy them 
  • Use beneficial insects such as parasitic wasps 
  • Biological pesticides like Bacillus thuringiensis (Bt) can be used as well

2. Aphids

Symptoms:
Small green, yellow or black bugs which gather on undersides of leaves and stems; they may cause curling of leaves and hinder plant growth.

Prevent & Treat: 

  • Spray plants with strong water jet to drive away aphids 
  • Ladybugs are good predators for these pests so introduce some into your garden or use insecticidal soaps or neem oil
  • Use beneficial insects such as lacewings or other natural predators.
  • Insecticidal soap or neem oil can be used

4. Spider mites

Symptoms

Tiny red or brown mites form fine webs on the undersides of leaves. They cause spotting and yellowing of the leaves.

Prevention and treatment

  • Increase humidity around plants
  • Spray with water to repel them
  • Use miticide or insecticidal soap

5. Cutworms

Symptoms

These pests cut young seedlings at the soil line, often killing the plants.

Prevention and Treatment

  • Use collars around seedlings to prevent pinworm access
  • Handpick at night
  • Apply diatomaceous earth around the base of plants

Integrated Pest Management (IPM)

Integrated Pest Management (IPM) is a strategy that combines several methods to control tomato diseases and pests. Learn how to do IPM in your garden here:

Crop controls

Practice crop rotation, use disease-resistant varieties, and maintain proper spacing for air circulation improvement.

Mechanical controls

Install barriers, traps, or handpick out pests.

Biological controls

Bring in natural enemies/predators and beneficial insects to manage pest populations.

Chemical controls 

Use pesticides/fungicides only if necessary as a last resort ensuring you follow label instructions.

Tomato diseases and pests can be challenging but with proper identification, detection, prevention/treatment measures; one can protect their tomatoes while having a healthy harvest too. Knowing what are some common tomato plant problems will help keep your garden thriving. Integrated pest management approach involves knowing various strategies which can be applied together towards controlling these diseases thus this article seeks to shed light on what these diseases might look like on tomatoes so that appropriate measures may be put into place early enough before they cause significant damage hence affecting productivity levels within our gardens.