Continuing on last week’s theme of fluffy bugs, I’m taking on the woolly aphids this week – here’s how to protect your garden and summer crops from pesky pests the organic way.
What are woolly aphids and what are they doing to my garden?
Did you know that there are more than 4,000 types of aphids worldwide? The woolly aphid is just one of these, but they seem to be everywhere right now – so let’s get cracking!
Woolly aphids are white and fluffy and often look like blobs on your trees, but when you take a closer look and get your hands in there, you will find lots of tiny white threads which, if you pull apart, reveals the aphids sheltering underneath. Woolly aphids generally appear on older trees and also on trees that have suffered stress, too much shade, not enough food or lack of water.
How do I know if I’ve got a woolly aphid problem?
Woolly aphids are particularly fond of apple and pear trees, often laying their eggs in the cracks of bark or damaged wood. They can form bubbles in your young wood and if you cut this bubble you will see thousands of eggs inside, which can then split to form cankers on your trees.
After the summer months, these damaging pests can move down to the roots of your trees where they can create untold damage out of sight from your vigilance.
What damage do woolly aphids do in my garden?
Aphids are known for their power to suck the life out of your plants. Not only will they weaken and destroy plants, they can also spread disease as they go. They secrete honeydew which in turn attracts ants and wasps, who feed on the sugary substance. Sooty mould will more than likely grow on the honeydew.
Over the past few years, I have had a few clients battling with these insects and, sadly, no matter what we have done, the tree has not recovered, as the infestation is so big and most of it unseen.
What can I do to control woolly aphids in my garden?
You can try to remove these pests with your fingers or a stick, squashing them as you go, which creates a real sticky red mess, but usually they will reappear in a week or two.
There are a few things you can try like EnSpray 99 and Pyretherum, but I find these only keep the population at bay.
Tip #1: The best preventative is to plant your tree well in the first place – mulch around the outside, plant with beneficial plants underneath it, and keep your soil and plant in optimum health.
Tip #2: Planting nasturtiums in your garden, somewhere away from your fruit trees, can act as a sacrificial crop, with woolly aphids infesting these plants instead and keeping them away from your trees. When the nasturtiums die back from infestation, carefully remove the plant and burn or dispose of wisely.
Tip #3: Members of the allium family, like onions, garlic and chives, can help repel many aphids and planting alyssum and borage around your garden will help attract beneficial insects that will eat up thousands of aphids a day.
Tip #4: In the summer months, plant a barrier of marigolds around or nearby your trees as the smell will repel woolly aphids.
Tip #5: The best advice I can give here is to keep your plants at optimum health, inspect them thoroughly when buying them and plant beneficial and sacrificial plants in your garden.
Good luck and happy gardening!
Header photo credit: Gardeners World
What if I’ve got wooly aphids on the bark of a outdoor terrace living bonsai tree? Which is a Chilean ULMO tree ?
Hey Therese, I wash the wound out with a harsh jet of water, wait until it is dry and then apply an oil spray, when they are in the bark they are difficult to control and the hotter it becomes the more they seem to explode, it is really good to keep an eye on them