Autumn Garden Pests: What to Watch For and How to Beat Them
As the leaves begin to fall and the temperatures drop, gardens take on a new rhythm, but so do the pests! Autumn's cooler temperatures and frequent showers create perfect conditions for unwanted visitors in your garden. Whether you're growing leafy greens, herbs or prepping the soil for winter crops, it's important to stay one step ahead of these seasonal troublemakers. Here's your guide to identifying the most common autumn pests and what you can do to protect your plants.
Slugs & Snails
With Auckland's damp autumn conditions, slugs and snails thrive. These slimy critters are most active at night and after rain, feeding on young seedlings and soft foliage like lettuce, spinach, basil and rocket.
How to spot them
Slime trails on leaves or soil and ragged holes in your plants. You may also see them lurking under stones, old leaves, or plant pots during the day.
How to control:
Hand-pick slugs and snails early in the morning or after rain.
Use pet-safe slug bait.
Reduce their hiding spots by clearing old leaves and plant debris.
Aphids
Aphids gather in large colonies on the soft, tender parts of plants and feed on sap, which weakens your crops and spreads viruses. They are most common in early autumn but can linger as long as the weather stays mild. Aphids in New Zealand can be green, black, yellow, brown, white, red or even orange
How to spot them
Look for clusters on the undersides of leaves and near new shoots. Leaves may curl, yellow, or look misshapen.
How to control
Hose them off with a strong spray of water.
Introduce beneficial insects like ladybirds to your garden.
Spray with natural options like neem oil.
Fungal Diseases
Excess moisture from autumn rains and cooler nights makes your garden a fungal hotspot. Powdery mildew, rust and downy mildew are common and can spread fast.
How to spot them
Powdery white patches on leaves.
Orange or brown rust spots.
Grey moldy growth or rotting stems
How to control
Improve air circulation by spacing plants properly.
Water at the base, not overhead and in the morning to allow leaves to dry before nightfall.
Remove and dispose of infected leaves promptly.
Caterpillars
The cabbage white butterfly is still active in autumn, and its green caterpillars love leafy greens like lettuce, spinach, and broccoli. Left unchecked, they can strip plants in days.
How to spot them
Holes in leaves or Small green droppings on or around the plant. You could also find green caterpillars hiding on the undersides of leaves.
How to control
Handpick caterpillars regularly.
Use insect mesh to cover vulnerable plants.
Encourage birds and beneficial insects into your garden.
Prevention is Better Than Cure
A healthy, tidy garden is the first line of defense against autumn pests. Regularly removing dead leaves, pruning back diseased plants, and clearing away garden debris can dramatically reduce pest habitats.
Our reliable green waste collection service makes it easy to dispose of plant waste after a tidy-up, helping you prevent pests from setting up camp in your garden. Stay ahead of autumn’s sneaky invaders and keep your garden thriving!
