Interactive lesson

Protecting the garden without chemicals, step by step

Interactive lesson: a garden that defends itself — prevention, the daily walk round, diseases, slugs and beetles, netting, natural allies and safe home remedies.

Free sample Chapters 1 and 2 (8 steps) are free. The full lesson comes with the Pests and diseases without chemicals module. Already bought? Unlock

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The whole lesson as text

1. A healthy garden

A healthy garden isn't sprayed, it's built.

3–4 year crop rotation — A 3–4 year break protects against soil-borne pests and diseases. Don't grow tomatoes and potatoes side by side.
Spacing and side-shooting — Correct spacing and removing side shoots keep the leaves dry and reduce blight, grey mould and powdery mildew.
Water at the roots — Water at the roots, in the morning. Mulch stops soil carrying spores from splashing onto the lower leaves.
Soil and flowers — Weak plants are the first victims; compost and living soil make them stronger. Flower strips feed the beneficial insects that eat aphids and caterpillars.

Why: Most problems come from the same few causes: the same crop in the same place, plants too close together, wet leaves, poor soil and not a single friend in the garden. Fix those, and problems become small and rare.

The aim is not a sterile garden, but a balance in which losses stay below 5–10 % of the crop.
On a seed packet, the letters after the variety name show resistance: V and F (wilts), ToMV (mosaic virus), PM (powdery mildew).

2. The walk round

A problem spotted early is a small problem.

10 minutes a day — Walk round the garden every day. For the first few weeks, take the walk-round checklist with you.
Undersides of leaves — Turn a cabbage leaf over: yellow egg clusters and caterpillars. On the tips of beans and peppers, look for aphids and ants.
10× hand lens — Many pests are smaller than a millimetre. A hand lens helps you see what is really on the leaf.
Photograph and write down — If you're not sure, photograph the leaf from both sides and ask an experienced grower, the RHS advisory service, Teagasc or your Extension office. Write in the log what you see and what you did.

Why: Walk the garden for 10 minutes every day, best in the morning. A problem caught early is dealt with by hand, while spraying "just in case", without knowing what the problem is, is a mistake.

Many "diseased" leaves are really drought, cold, hunger or sun.
Check the undersides of brassica leaves at least twice a week for cabbage white eggs.