Welcome to my website where I gather information about plant pests and pathogens preying on gardens in my local area in Melbourne. I want to live in harmoney with nature and so I use exclusion techniques and natural predators to protect my edible and ornamental plants instead of using poisonous chemicals...................John Ashworth 27th July 2015.
Latest Update 22nd January 2018. Aphids (Blackfly).
Blackfly are a relative newcomer to my vegetable garden, but recently they have made a nuisance of themselves on my alliums.
I use a foliar spray of aerated compost tea in late winter to encourage an early microbial response to young blackfly, but if I find a small colony developing, I disperse them with jet of water from a hose. It pays to be vigilant and deal with them before they infest your crop.
If dispersing them doesn't help, I use diluted organic horticultural oil as a thorough foliar spray to smother them.
Why Blackfly are a Pest.
They have only attacked alliums and sweetcorn so far in my garden, but I watch all my edible plants for early signs of their presence so I can control them before they become a significant problem.
You can use a jet of water to clear blackfly off any affected plants, but unlike greenfly, some of them will return to your plant again. Repeated applications eventually remove them for good.
I have no direct evidence, I believe that regular monthly foliar sprays
of activated aerobic compost tea helps strengthen plants so they can
resist the attentions of aphids.
It pays to be vigilant and deal with any pest before they do too much damage.
In summer, look out for ants as they breed colonies of aphids for the sugary secretions they provide. Track the ants until you find the aphids colony they are nurturing.
A foliar spray of organic horticultural oil or even home made organic soap solution will kill aphids by smothering them.