🐛 Pests & Diseases
The most effective organic pesticides: a complete usage guide
A complete usage guide to the organic pesticides that really work in the garden: which pest or…
Garden pests and diseases: identify and treat without chemicals
Almost all garden pests and diseases are best controlled - and more cheaply - when caught early and the cause is treated, not just the symptom. A healthy plant in living soil, well watered and not over-fed, resists aphids and fungi far better than a stressed one. That's why the first line of defence is always cultivation: the right design, correct watering and biodiversity (having ladybirds, lacewings and birds that eat the pests).
In this section you have guides to identify the problem from what you see and treat it with what actually works: common pests (aphids, scale, whitefly, red spider mite, caterpillars, snails) and their natural solutions; fungi on plants (powdery mildew, downy mildew, rust, botrytis) - how they differ and how they're treated - and a guide to the most effective organic pesticides (potassium soap, neem oil, Bacillus thuringiensis, sulphur, copper) with doses and timing.
The recommended order of action: identify correctly - cultural and mechanical measures (remove by hand, prune the affected part, traps) - biological control (beneficial fauna, Bt) - organic contact treatments - and only as a last resort, a stronger plant-protection product, always respecting intervals and pollinators.
Pests & Diseases articles
🐛 Pests & Diseases
Fungi on plants: identification and treatment
A complete guide to identifying and treating the most common fungal diseases in the garden: powdery…
🐛 Pests & Diseases
Common garden pests and natural solutions
A complete guide to identifying and naturally treating the most common garden pests: aphids, scale,…
Frequently asked questions
How do I get rid of aphids naturally?
A jet of water knocks off a good part; then diluted potassium soap sprayed on the underside of the leaves every 5-7 days until under control. Encourage ladybirds and lacewings (don't use broad-spectrum insecticides), plant nasturtiums as a trap plant and check for excess nitrogen fertiliser, which triggers aphids.
What's better against fungi, sulphur or copper?
Wettable sulphur is preventive and an early cure against powdery mildew and also acts on red spider mite; don't use it above 28-30 °C. Copper (Bordeaux mixture, oxychloride) is preventive against downy mildew, rust and bacterial diseases. Many gardeners alternate both. In either case, prevention is better: wet the leaves little, ventilate and don't water at night.
Are organic pesticides really effective?
Yes, if used well: in time (at the first symptom, not when the pest is out of control), at the right dose, wetting the underside of the leaves well and repeating as the label indicates. They're contact products and last less than chemicals, so 2-3 applications are needed. In exchange, they don't harm beneficial fauna or leave residues.
How do I know if it's a pest or a disease?
Pest = a creature (even a tiny one): aphids, scale, mites, caterpillars, whitefly; there's usually sticky honeydew, chewed or deformed leaves and sometimes ants. Disease = fungus, bacterium or virus: spots, white or orange powder, rot, leaves that yellow or dry without a visible creature. A hand lens and looking at the underside of the leaves solve almost every doubt.
Does neem oil work for all pests?
Neem works well against aphids, whitefly, thrips, young scale and red spider mite, and has some preventive fungicidal effect. It acts as a repellent and insect growth regulator, so its effect is progressive, not instant. It's not effective against snails or soil pests, and it's best applied late in the day.
How do I control snails and slugs without poison?
Combine several methods: hand-picking at dusk or after rain, barriers of eggshell, ash or copper around sensitive plants, beer traps, removing hiding places (boards, pots, leaf litter), watering in the morning instead of at night, and encouraging their predators (hedgehogs, toads, birds, ground beetles).