Pest & Disease Control

Pest bugs are our messengers and can tell us about many problems with our greenhouse or garden.

However, when it comes to plant diseases there are no quick cures. The best choices include taking preventative measures to keep your green house clean and growing plant varieties that are resistant to any particular disease you are concerned about. Changing any of the climate factors – temperature, light and humidity, moisture level and plant location are all excellent ways to reduce and control disease.



Organic Controls: Destroy with boiling water. Plant pennyroyal, spearmint or tansy to repel. 

Chemical Controls: Bayer Spray, Amdro Granules


Tiny, pear-shaped, often light green in color. Adults may be winged or wingless. Aphids suck sap, excreting a honeydew, sticky substance. They cause wilting and curling of leaves and flowers.

Organic Controls: For small infestations, wipe with soapy water and use Whitefly & Aphid Traps. For larger infestations, spray frequently with soapy water or a product such as 3-in-1 Safer’s Garden, or 70% Neem Oil. Plant pennyroyal, spearmint, tansy or garlic to repel. Ladybugs are also very effective.

Chemical Controls: Malathion, OrthoMax, Bayer Systemics, Acecap Fortress, XClude


Nocturnal caterpillars that are the larvae of several different moth species. They cut down young plants when they feed, and are capable of destroying entire fields by feeding on both roots and foliage.

Organic Controls: Handpick caterpillars after dark. This is often most productive following a rain or thorough watering. Place cardboard collars (or toilet paper tubes) around transplant stems at planting time.

Chemical Controls: Malathion

Mealy Bugs

These sapsuckers are often confused with aphids and produce a wax-like cottony substance that looks like cotton on your plant. They are white to tan and oval in shape. Find them near buds, on leaf bases, and leaf veins.

Organic Controls: For small infestations, wipe with a Q-tip or cotton ball that has been dipped in rubbing alcohol. For larger infestations, spray with a product such as 3-in1 Safer’s Garden Spray, or 70% Neem Oil. A good beneficial beetle control is the “mealybug destroyer” –Cryptolaemus montrouzieri.

Chemical Controls: Ortho Max

Spider Mites

These tiny arachnids (8 legs) are impossible to see without a magnifier. They range from yellow to brown to reddish. Look for their telltale webs on the underside of leaves and at growing tips. They puncture leaves and suck the contents. Leaves become yellow and mottled.

Organic Controls: Spray strong blasts of water on the underside of leaves to knock them off. They are encouraged by hot, dry conditions. Spray water in the greenhouse regularly to create a more humid atmosphere. Use 3-in-1 Safer’s Garden Spray, 70% Neem Oil or a similar product for larger infestations. Also there are a number of effective beneficial predatory mites available depending on your greenhouse temperature range and time of the year. Check with our staff about your particular needs.

Chemical Controls: Organocide, Captain Jack’s Dead Bug Spray, Dr. Doom, Azatorol


Very tiny, yellow to brown insects with a cigar-like shape. Find them on the underside of leaves, in flower buds and flowers. They begin their life in the soil and then surface and become winged. They can multiply and do much damage quickly! They feed on leaves. They are also known for transmitting diseases including TSWV – tomato spotted-wilt virus.

Organic Controls: Spray with 3-in-1 Garden Spray or 70% Neem Oil. Destroy badly infected plants.

Chemical Controls: Malathion


Small, flying, translucent (maturing to become white) insects. All stages – eggs, immature crawlers and adults – suck sap from the underside of leaves. They can cause wilting, yellowing, spotty marks, deformation, and curling of leaves and flowers. Often they secrete a honeydew sticky substance on leaves and fruit; which in turn attracts a black, sooty mold.

Organic Controls: Gently sweep them up with a small vacuum cleaner. Spray with 70% Neem Oil, or 3-in-1 Garden Spray. Use Whitefly & Aphid Traps to control adults. Encarsia Formosa, a small parasitic wasp, is a good beneficial insect control.


Blossom End Rot

A tomato disease in which a dark brown patch develops on the base of the tomatoes. Generally caused by uneven watering.

Organic Controls: Keep the growing medium wet but not soggy. Avoid splashing water on the leaves and fruit. Increase air circulation and lower the humidity level.

Chemical Controls: Rot Stop


Appears as a fluffy gray or brown mold on leaves and stems of soft-leaved plants. Associated with humid, cool weather conditions.

Organic Controls: Remove all diseased areas, reduce watering and increase air movement. Spray with GreenCure or Serenade.

Chemical Controls: Rose & Flower Dust, Serenade

Damping Off

Destructive fungi attack the roots and stems of seedlings causing rot. Seeds may decay in the soil and never germinate. Stems can rot at the surface and seedlings wilt and die. Roots can rot after the seedling has germinated and stunts it, then the plant dies. No cure.

Preventive Measures: Use only sterile germination medium. Sow seeds thinly. Do not over water. Keep medium at recommended propagation temperature.

Chemical Controls: Captan


Powdery Mildew – A white downy coating that appears on leaves and stems.

Controls: Remove badly affected plant parts. Spray with bicarbonate of soda (2 tsp. to 1 liter of water). Spray larger infestations with GreenCure or Serenade. Improve ventilation.

Chemical Controls: Infuse