Working With Nature: Pests, Plants, and Finding Balance

Michelle Sulz, P.Ag.

“The garden suggests there might be a place where we can meet nature halfway.”

— Michael Pollan

Every Garden is an Ecosystem

• Plants
• Insects
• Microbes
• Animals
• Weather
• You

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When one thing shifts, others respond.

A plant’s problems are often a response, not a failure.

Common Plant Stressors

• Abiotic (Non-Living)
• Extreme temperatures
• Wind
• Drought/waterlogging
• Too much/little light
• Poor soil conditions
• Physical damage

• Biotic (Living)
• Insect Pests
• Diseases
• Weeds
• Animal damage

We often notice biotic stressors first, but often they are secondary to abiotic stress.

Why This Plant? Why Now?

When pests show up, pause before reacting. Ask questions like:

• Why this plant and not the one beside it?
• Why this week and not last week?
• How has the weather changed?
• Has watering been consistent?

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Outbreaks are rarely random They are often signals

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Responding in the Right Order

Environmental Balance

• Build healthy soils with lots or organic matter
• Water consistently
• Manage plant spacing & airflow

If the foundation is strong, the next two layers are needed far less

Biological & Physical Tools

• Hand remove pests or prune out disease
• Encourage beneficial insects
• Use physical barriers like row covers
• Release beneficial insects

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These methods reduce pressure without collapsing the ecosystem

Targeted Treatment

• Remove heavily infested plants
• Apply biological controls
• Use insecticidal soap or neem oil as a spot treatment

These methods are reserved for where intervention is required and should be a targeted

Case Study #1: Grasshoppers

• Establish healthy plants early
• Improve soil moisture retention
• Vacuum or hand remove
• Encourage birds, frogs, and toads
• Apply bait around the perimeter

Case Study #2: Fungus Gnats

• Avoid overwatering, allow the soil surface to dry between waterings
• Use sticky cards to monitor adults
• Release beneficial nematodes (e.g. Entonem)
• Apply BTI

Case Study #3: Spider Mites

• Avoid drought stress
• Increase humidity
• Prune out infected leaves
• Release beneficial mites or insects
• Remove heavily infested plants
• Use Neem oil to spot spray

Case Study #4: Aphids

• Avoid excess nitrogen
• Water wash or prune out small infestations
• Support native and naturalized beneficial insects�(e.g. lady bugs)
• Release beneficial insects �(e.g. ‘Crazee Mites’)
• Spot spray insecticidal soap or neem oil

Case Study #5: Cabbage Moth/�Cabbage Worm

• Rotate where you plant your brassica (cabbage family) crops
• Encourage vigorous plant growth
• Use tents or row covers
• Hand pick worms
• Encourage parasitic wasps
• Apply BTK

Beyond the Pyramid: �Targeted vs. Broad Pesticides

Targeted / Biological

• Narrow mode of action
• Lower impact on beneficial insects
• Works best with correct timing & contact

Chemical Pesticide

• Broad-spectrum toxicity
• Affects pests AND beneficials
• Disrupts ecosystem balance
• May trigger rebound outbreaks

“Define success on your own terms, achieve it by your own rules.”

— Anne Sweeney

A Few Resources

• The Bug Lady – Beneficial Insects and nematodes
• Canadian Tire – BTK
• Neem Oil – Amazon.ca

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Thank You!

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Questions?

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