Slugs and Snails

These non-discriminating nocturnal nibblers feed on desirable plants as easily as on decaying vegetation. They typically chew the margins of leaves and petals and also leave holes in them. Plus, they strip off chunks of stem, causing young plants to collapse, and graze the skin and peel of fruit and vegetables. Seedlings and any juicy young shoots of established plants, flower and leaf buds, and newly unfurled foliage are particularly vulnerable. Snails can climb up walls and tall plants to reach their food, while some slugs live underground. Key signs: Look out for tattered leaves and ragged flowers that indicate the presence of slugs and snails.

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Organic Controls

Check under and around the rims of pots, beneath ledges, in piles of rocks or logs, and on evergreen shrubs where slugs and snails roost, and pick them off. Beer traps will lure them in at night. Slugs and snails are also deterred by copper strips, which give them an electric shock when they pass over them, and cloches made from plastic bottles. Diatomaceous earth also works to deter their travels.

Beer in a cut-off plastic bottle lures and traps slugs (Image 1). Use the top half of the bottle to protect seedlings (Image 2). Fit copper tape around pot rims (Image 3). Surround vulnerable hostas with copper slug collars (Image 4).

Aphids

These pests are commonly known as greenfly, although other colors exist and some have a woolly wax coating. Aphid species number over 4,000 worldwide, and many favor specific plants. They reproduce rapidly in spring and summer.