Mossy saxifrage

Vine weevil

What you will see

Adult beetles notch leaf edges; larvae eat the roots and the plant wilts.

The source says: it is among the perennials prone to damage.

How to protect

1. Prevention

   • When planting and repotting, check the roots and remove larvae.
   • Encourage birds, toads, hedgehogs and ground beetles.
2. By hand May to SeptemberEvening collection of adult beetles by torchlight; pick larvae out of the roots and soil.
3. Biological August to early September, soil warm enoughNematodes (Steinernema, Heterorhabditis) watered into the soil against the larvae.

Aphids

What you will see

Colonies of tiny insects on shoots and buds, sticky honeydew, curled leaves.

How to protect

1. Prevention

   • Check plants regularly from spring.
   • Encourage ladybirds, hoverflies, lacewings and parasitic wasps.
2. By hand as soon as it appearsRub off colonies by hand or wash them off with a jet of water.
3. Biological spring to summerRelease lacewing larvae, aphid midge larvae or ladybirds.
4. Gentle spray in a heavy infestation, repeatPotassium soap (fatty acids) or plant oil.
5. Chemical — only when nothing else helps only as a last resortA product authorised in your country against aphids.

Slugs and snails

What you will see

Irregular holes in soft leaves and young shoots and slime trails; they feed at night.

How to protect

1. Prevention

   • Plant sturdy potted plants, not delicate young seedlings.
   • Water in the morning, not the evening (evening watering helps them move around).
   • Encourage their natural enemies: birds, hedgehogs, toads, ground beetles.
2. By hand evening, after rainPick them off by hand on damp evenings and take them far away. Traps: hollowed-out citrus halves placed cut side down, or sunken containers of beer; check in the morning.
3. Biological when the soil is warm and moistSlug-specific nematodes (from a biological control supplier) are watered into the soil.
4. Chemical — only when nothing else helps according to the product labelLast resort only: a product authorised in your country against slugs and snails. Try non-chemical methods first.

Spider mites

What you will see

Leaves are speckled and bronzing, with fine webbing on the underside.

How to protect

1. Prevention

   • Reduce dust and water stress; do not use broad-spectrum insecticides, which cause mite outbreaks.
2. By handA strong jet of water on the underside of leaves.
3. Gentle sprayInsecticidal soap or oil, thoroughly on the undersides; only after mites are confirmed.

Root and crown rot

What you will see

Softening of the crown and roots; the plant wilts and browns despite watering.

How to protect

1. Prevention

   • Free-draining soil, no waterlogging (especially in winter).
   • Do not plant too deep.
2. By hand at the first symptomsDig up the affected plant; improve the soil with drainage; do not replant in the same place.