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Horticulture 1000
HT1103 - Plant Management 3 - Healthy plants
Plant Management 3 Pests
1

Healthy plants

This hosta plant is healthy and has large, complete leavesThis hosta plant is healthy and has large, complete leaves.

Healthy plants grow strongly.

The leaves are firm. Flowers, fruit and root systems are well formed. They have no signs of pests and diseases.

 
The hosta leaf is being eaten by a snailThe hosta leaf is being eaten by a snail.

Pests, diseases, and environmental factors can all affect the health of plants.

Unhealthy plants show these signs:

  • leaves wilt, curl or change colour
  • stems and roots are stunted or dead
  • flowers and fruit are not well formed.

In this photo the hosta leaf is being eaten by a snail. This will expose the plant to further damage by micro-organisms and reduce the photosynthesis rate.

 

When pests or diseases affect a plant they show specific signs. A pest is an animal that damages plants. Some common examples include snails, white butterfly caterpillars and aphids.

Diseases are caused by bacteria, fungi or viruses. Diseases interfere with plant growth and development.

Complete Activity 1 in your workbook

Key points   Key points

  • Healthy plants have firm leaves, well-formed flowers and fruit, and well-developed root systems.
  • Unhealthy plants show damage to leaves, stems, roots, flowers or fruit.
  • A pest is an animal that damages plants.
  • Disease is caused by bacteria, fungi, and viruses.
 

What's next?

Go to: 2 Pests.

Plant Management 3 Pests