Common Pests and Diseases

At St. Jago Farm and Hardware Supplies Limited, we are aware that time and money can be wasted if pests affecting our crops are not correctly identified

Main Classification of Pests

It might surprise you to know that the term “pest” extends past insects and can include :

  • Fungus

  • Viruses

  • Bacteria

  • Weeds

  • Vectors

What can happen if you treat the wrong pest?

Look at the picture below. What is the problem here? Blight? Nutrient Deficiency? Herbicide damage?

See The Impact Of Some Of The More Common Pests


Weeds are one of the most under-estimated pests as they can decrease your yield by more than 50%. Therefore, identifying the type and treatment is important to make sure you get the most from your field.

Pineapple field with Weeds
Pineapple field without Weeds


One of the most common and destructive insect pest of common vegetables grown in Jamaica are Whiteflies.

  • Whiteflies feed by extracting plant fluids with sucking mouth parts

  • Damage then appears as yellow leaves and stunted growth of the plant

  • If damage is left untreated, the plant dies

Control of Whiteflies- Inspect plants about 2 times per week to detect their presence. Remove infested sections of plant to reduce spread in the earlier stages.

Codigo, N-Oil and Rotaprid are products that give excellent control of whiteflies.


Some of the Fungal diseases affecting plants are

  • Damping Off

  • Root Rot

  • Powdery and Downy Mildew

  • Early and Late Blight

Early Blight in Tomatoes

Early Blight in Tomatoes 1
Early Blight in Tomatoes 2
  • Early blight is one of the most common tomato diseases, occurring nearly every season wherever tomatoes are grown

  • It affects leaves, fruits and stems and can be severely yield limiting when susceptible cultivars are used and weather is favorable

  • Severe defoliation can occur and result in sunscald on the fruit.


  • Initially, small dark spots form on older foliage near the ground

  • Leaf spots are round, brown and can grow up to half inch in diameter

  • Larger spots have target-like concentric rings. The tissue around spots often turns yellow

  • Severely infected leaves turn brown and fall off, or dead, dried leaves may cling to the stem

Damping Off

Damping Off– is a condition caused by several different pathogens that kill or weaken seeds or seedlings before or after germination.

Damping off Disease

  • Control Damping-Off by mixing your potting soil with a solution of Calguard prior to sowing seeds

  • Damping off is seedling death Phytophthora spp., Thielaviopsis basicola

  • Seedlings may start to grow and then wither, break off or collapse and die.

Stem Infections

  • Seedling stems are infected at or just above the soil line. The stem turns brown, sunken and dry (collar rot).

    If the infection girdles the stem, the seedling wilts and dies.

  • Stem infections on older plants are oval to irregular, dry brown areas with dark brown concentric rings