Aphids And Bonsai, What Are They And How To Treat Them - Bonsai-En

Aphids And Bonsai, What Are They And How To Treat Them

How To Get Rid Of Aphids On Bonsai


Before we defeat our enemy we must first understand our enemy, After all any pest that try's to attack your bonsai are the enemy.


What Are Aphids?

Aphids are tiny little sap sucking pests, No I'm not calling them names that's what they actually are. Aphids congregate in masses on your trees and suck the sweet sap from your tree, Female aphids can also reproduce without a mate so they can multiple rapidly over a single season, any infestation left unchecked can cause some serious weakening of your trees. Aphids can come in all sorts of colours from brown, black, yellow and green. They are very small so it takes some careful investigation of your trees to see an infestation, but there are some tell tale signs which we will talk about now.



How To Identify An Aphid Infestation

After aphids have eaten the sap from the tree they then produce a sweet sticky excretion called "Honey Dew", Often times you can see this honey dew on your benches as it drips from the aphids off the branches. You will know its honey due as it will be very thick in texture and very sticky, it will appear randomly around your pot and may even be running down the sides of your pot. Another dead give away is ants! ants will actually protect the aphids, in return the aphids will allow the ants to feed on the sweet honey dew. So if you see a tree that has ants all over it then there's a good chance you might have aphids.

Another sign that you have aphids maybe be sooty mould, the honey dew they excrete can cause these black spots to appear on your leaves, This isn't always caused by aphids but it can be a sign.


How To Prevent Aphids On Bonsai

You've probably heard this before but the best way to prevent any kind of pest on your bonsai is to have a healthy tree. Make sure you have been fertilising well and that your fertiliser has a good amount of potassium in it. The stronger your tree is the more natural defence it has against pests. i have also found that the years i haven't done a winter spray of lime sulphur i have been more prone to aphid infestations at the end of winter / early spring. Don't spray your Australian natives with lime sulphur though, it will cause the entire tree to drop its leaves. Natives aren't very prone to aphid infestations any way, They have their own enemy's. The rest of your trees may benefit from a beginning of winter and mid winter spray of lime sulphur though which will combat both pests and fungal infections which are more prominent during winter. 


How to Treat Aphids On Bonsai

There are a few ways to go about this, 1 simple way is to blast them out of your tree with the hose. Aphids generally don't hang on very tight so a nice solid stream of water evicts them from your tree pretty quickly, this is a nice easy free way to go about it but it does come with some down sides. When blasting your tree with a stream of water that's strong enough that it can remove the aphids might also do some damage to your tree or wash away your soils surface, This also doesn't get rid of the aphids permanently and they may just move into another tree near by.

Another method is using a pest oil, Pest oils are a contact spray and is applied directly to the aphids, Pest oils will clog the pores they use to breath and suffocate them so it is a very effective treatment, but once again there are some downsides. When using oil you need to be carful of the species, junipers and pines for example should never have any kind of pest oil applied as it will clog their pores which could be very bad for the tree. Pest oils in mid summer can also cause some leaf burn if left to sit in direct sunlight. 

The next method is using Imidacloprid which we sell in the form of Congaurd. This can be mixed up as a spray and used with a Pest And Disease Spray Bottle. Congaurd is a contact spray that will kill the aphids with no negative effects. It can be used on a wide range of species and will treat the aphid infestation fast, Make sure you apply the spray on a day that hasn't got a high chance of rain as you will want the spray to work before it gets washed away. When applying any kind of treatment always take precautions, wear safety goggles to prevent getting spray in your eyes if the wind blows ( trust me its a problem) lay newspaper over your soil surface so you can give your foliage a good drench without too much entering your root ball ( although congaurd is systemic i still take this precaution ).


I hope this has helped you understand aphids on bonsai a little better and has given you some ideas on how to identify, prevent or treat aphids.


Until Next Time, Enjoy Your Bonsai Journey.

Leave a comment

Please note, comments need to be approved before they are published.

  • Brach Cutter + Scissor Bundle

    These are the 2 most essential tools in bonsai, so why not buy them together and save? Both tools are high quality Japanese Steel from one of the most trusted brands in bonsai. Click the image above to get your discount.

  • Essential Scissors Bundle

    In bonsai you will need a set of scissors to cut the foliage on top and the roots down below. Save when you buy both pairs with this bundle offer. Both tools are high quality Japanese Steel from one of the most trusted brands in bonsai. Click the image above to get your discount.

  • Protect Your Tool Investment

    When investing in high carbon steel tools it is wise to protect them with tool oil to maintain optimal performance. Save 10% when you bundle the tool oil and the applicator together. Click the image above to get your discount.

  • Cut Paste Bundle

    When we trunk chop or break branches during wiring it is best practise to get the wound covered straight away with cut paste or putty. Putty is used for larger wounds while paste is used for cracks, breaks and grafts. Get both today at a discount price when bought as a bundle. Click the image above to browse our range and select your pastes.

  • 100g Bonsai Wire Deal

    Wiring you bonsai trees will be a large part of your practise, make sure oyu have all the wire you need on hand and ready to go with our 100g bonsai wire deal. Add any 5 rolls to your cart and only pay for 4! Click The Image Above To Choose Your Rolls.

  • 500g Bonsai Wire Deal

    If you are a serious wiring machine and require a little extra wire on hand our 500g rolls are perfect, What makes them even better is if you add any 5x Rolls to your cart you will get $10 off. Stock up and be ready for any wiring job. Click The Image Above To Choose Your Rolls.

1 of 6
bonsai artist with bonsai tree

Author : Joshua Hooson

Joshua Hooson is an author and enthusiast of the art of bonsai. He has built his knowledge and understanding of bonsai through a combination of self-experience, lessons learned through hands-on practice, and extensive research. His articles reflect his passion for the subject and offer insights gained through his own personal journey in the world of bonsai. All the information provided in his works is a result of his own experiences and the knowledge he has gained through his studies. He is dedicated to sharing his love of bonsai and helping others grow in their understanding and appreciation of this ancient and beautiful art form.

Learn Bonsai Online With Josh