Gardening can be an immensely pleasurable and rewarding experience. However, there can be challenges when it comes to harmful insects, diseases, and other issues that may affect your plants. We’ve put together this guide with photos, remedies, and links to help you have a successful crop and manage some of the most common issues gardeners and growers face. We encourage you to talk to a local expert, Master Gardener or Horticultural Society or local ministry if you can’t find what you’re looking for here.

Common Plant Diseases

Mosaic Virus

Early/Late Blight

Powdery Mildew/Downy Mildew

Blossom End Rot

Leaf Spot


Bacterial Wilt


Black Spot


Verticillium Wilt

Fusarium Wilt

List of Beneficial Insects



Parasitic Wasps

Native Bees

Praying Mantis

List of Harmful Insects





Striped/Spotted Cucumber Beetle


Cabbage Looper Caterpillar



Spider Mites

Flea Beetles





Boxelder bug

Coddling Moth

Fungus Gnat

Japanese Beetles

Leaf Hopper


Squash Vine Borer

Tomato Hornworm / Tobacco Hornworm

Natural Pest Control Products

Insecticidal Soap

Diatomaceous Earth


Nutrients and Deficiency Symptoms

Phosphate: Deficiency symptoms include stunted growth. Leaves are dark green developing toward red or purple. Leaves may have necrotic spotting and older leaves may turn brown

Nitrogen: Deficiency symptoms include yellow of light coloring, starting with lower leaves. Drying and shedding of older leaves. Growth is stunted, stems are spindly, and yields are severely depressed

Potash: Stunted growth, tendency to wilt, weak stems. Older leaves may have bleached spots; margins may appear tscorched. Leaves may curl

Magnesium: Bleaching between the veins of older leaves. Leaves tmay be stiff and brittle or may appear withered

Calcium: Soft growth, deformed young leaves. Decreased growth of leaf and root tips

Sulfur: Stems are thin and brittle. Young leaves are pale or yellow. Slow, limited growtht

Copper: Leaf tips bleached, twisted, or curled. Leaves may turn dark blue-green, wilt, and drop. Plant appears withered tand seed stalk may wilt

Iron: Bleached or yellow new growth. Leaf tips and margins tappear dry

Manganese: Bleaching between the veins, dead spots at the base of young leaves. Young leaves may drop

Molybdenum: Stunted growth. Leaves are pale or yellow, withered, and may have dead spots or rolled margins. Begins with middle leaves, then moves to older leaves

Zinc: Bleaching between the veins along the midrib and leaf margin beginning with older leaves. Leaves may be thickened, and premature leaf death can occur. Sometimes short internodes are present, and bud formation may be decreased. This is the most common mineral deficiency

Additional Resources