The most common garden pests and how to control them effectively without harming the ecosystem

Aphids: Identification, Damage, and Ecological Treatments

Aphids are small insects that feed on plant sap, causing significant damage if not controlled in time. They're especially common on plants like geraniums, fuchsias, and rosemary. They're identifiable by their oval bodies, colored anywhere from green to brown or red.

Symptoms of an aphid infestation include yellowing leaves, stunted growth, and a sticky "honeydew" residue that builds up on leaves and stems. Aphids can also transmit diseases to plants, which can kill them if you don't act quickly.

To control aphids ecologically, you can use methods such as manually cleaning the plants or applying coconut soap or neem oil. Coconut soap is an inexpensive, effective option, costing around $5 a liter, and should be applied every 7 to 10 days. Neem oil is pricier (around $10 for a 100 ml bottle) but works well long-term and has a repellent effect.

• Clean plants with a diluted coconut soap solution (1 tablespoon per liter of water) every 7 days.
• Apply neem oil every 10 to 14 days, especially on the most vulnerable plants.
• Use a garden hose to rinse plants and physically remove aphids.
• Introduce beneficial insects such as Aphidius colemani if the infestation is severe.

Red Spider Mites: When They Appear and How to Get Rid of Them Without Harsh Fungicides

Red spider mites are a common problem in gardens, especially on plants like rosemary, thyme, and lavender. This pest is identified by its small, reddish body and fine legs. It appears mainly in summer, when temperatures are high and humidity is low.

Damage caused by red spider mites includes dehydrated plants, leaf drop, and reduced growth. Although they don't feed directly on the plant tissue itself in the way aphids do, their presence can point to a humidity or ventilation problem in the garden.

To eliminate red spider mites without resorting to harsh fungicides, you can use methods such as applying neem oil, setting out homemade baits, and improving garden ventilation. Neem oil is a safe, effective option costing around $10 for a 100 ml bottle. It should be applied every 7 to 10 days.

• Use a diluted neem oil spray (10 drops per liter of water) every 7 days.
• Set out homemade baits made with white vinegar and sugar in affected areas.
• Improve garden ventilation to prevent humidity from building up.
• Clean plants with a garden hose to remove eggs and adults.

Cottony Cushion Scale and Armored Scale: Differences and Treatment

Scale insects show up in two main forms in gardens: cottony cushion scale and armored scale. Both are common on plants like cacti, rosemary, and geraniums, but they differ in appearance and treatment.

Cottony cushion scale looks like a soft, white or pinkish cottony mass that clings to leaves and stems. Armored scale, on the other hand, is harder, with a shield-like appearance and a brown or black color. Both feed on plant sap and cause similar damage, but they require different treatments.

To treat cottony cushion scale, you can use coconut soap or a neem oil spray. For armored scale, a natural insecticide such as neem oil or a white vinegar and water solution is recommended. Both treatments should be applied every 7 to 10 days to ensure they're fully eliminated.

• Apply a diluted coconut soap spray (1 tablespoon per liter of water) every 7 days.
• Use neem oil every 10 to 14 days to treat both forms of scale.
• Clean plants with a garden hose to remove eggs and adults.
• Apply a white vinegar and water solution (1:1) to treat armored scale.

Caterpillars and Larvae: Manual, Biological, and Chemical Control

Caterpillars and larvae are common garden pests, especially on plants like tomatoes, lettuce, and cucumbers. They're identified by their elongated bodies, colored anywhere from green to brown. They're especially active in spring and summer.

Damage caused by caterpillars includes destroyed leaves, stems, and fruit. To control them effectively, you can use manual, biological, and chemical methods. Manual control works well for small infestations, while biological control suits organic gardens better.

For manual control, inspect plants daily and remove caterpillars by hand. For biological control, you can use beneficial organisms like Bacillus thuringiensis (Bt), which is safe for the environment. For chemical control, a natural insecticide such as neem oil or coconut soap can be used.

• Inspect plants daily and remove caterpillars by hand.
• Use Bt every 7 to 10 days, especially in areas with a high density of caterpillars.
• Apply a diluted coconut soap spray (1 tablespoon per liter of water) every 7 days.
• Use neem oil every 10 to 14 days as a preventive measure.

Slugs and Snails: Physical Methods and Ecological Baits

Slugs and snails are nocturnal pests that feed on plant leaves and fruit. They're especially common in humid, shady gardens. They're identified by their moist bodies and ability to move quickly across surfaces.

Damage caused by slugs and snails includes destroyed leaves, stems, and fruit. To control them ecologically, you can use physical methods such as stone or sand barriers, along with homemade baits made from vinegar, sugar, and water.

Homemade baits are an effective, inexpensive option, costing around $2 per container. They should be placed around plants every 3 to 5 days. You can also use physical barriers such as stones or sand to stop slugs and snails from reaching your plants.

• Place homemade baits made with white vinegar, sugar, and water (1:1:1) every 3 to 5 days.
• Use stone or sand barriers around plants to stop slugs and snails from reaching them.
• Inspect plants at night with a flashlight to check for slugs and snails.
• Clean plants with a garden hose to remove eggs and adults.

When to Call a Specialist and When to Handle It Yourself

It's important to know when to handle a pest problem yourself and when it's worth calling in a specialist. If the infestation is small and involves common pests like aphids or slugs, you can manage it with ecological methods. However, if the infestation is severe or involves resistant pests, such as armored scale or red spider mites, it's a good idea to call a professional.

Professionals can offer tailored solutions, including specific insecticides or biological control methods. They can also identify pests that aren't visible to the naked eye and offer recommendations to prevent future infestations.

To handle it yourself, follow the ecological control recommendations, such as using coconut soap, neem oil, and homemade baits. Inspect the garden regularly and apply treatments every 7 to 10 days, depending on the pest.

• Handle it yourself if the infestation is small and involves common pests.
• Call a specialist if the infestation is severe or involves resistant pests.
• Inspect the garden regularly to catch pests early.
• Use ecological methods to minimize the impact on the ecosystem.