Oh my poor cherry tree!!!

I have paving flags on the floor of my greenhouse and in the center gravel , and in the past two weeks had seedling tomatoes sprout.

 

Ah! ... Right then, I just uncurled a leaf and black fly infestation!!!! Not on all leaves though, just on some. It's a bit late now because I have no cherries. Should I still spray it with soapy water??? Also next season should I keep spraying it from the blossom stage because it looks like they have got me for the last four years!!! Will soapy water harm the blossom? Forgive my ignorance.

 

over the winter hang some peanuts or the like to get the birds into the garden and they will help reduce that over winter as eggs in the bark and branches

 

Ok ... I have sprayed it with soapy water but had to guess the solution ratio (water to fairy liquid!). How often do I spray it. Should I spray it from the blossom stage next year?

 

before it has flowered or after NOT WHEN IN BLOOM you will kill the pollinating insects ie bees , and only spray when you see them

 

Thank you all for that. I have plenty of birds in my garden but I will definitely hang a feeder in my cherry tree as well now. Fingers crossed next year I will get more than one cherry!

 

That's a shame, I had a cherry tree a few years back and I never saw a single cherry but that's because the birds always got there first!

This article may help, I am not sure if soap water will do too much good, though I didn't realise that ladybirds would actually benefit in this case! You learn something new every day!

An article on Garden Seeker says that:

"The one good thing about Black Fly - or Blackfly - is that they are easy to see. Sometimes the other closely related aphid - the Greenfly, is not seen until it has taken a stranglehold on its plant meal.
As with all other Aphids, Black Fly is a sap sucker. It literally sucks the host plant to death. A little bit of exaggeration, in that it departs the plant that is giving it a feed, before it dies. A dead plant is of no use to this sap sucker!
As Black Fly are easy to see, we have the advantage of being able to deal with it - getting rid of it - before it can do too much damage. Even when we see the seemingly devastating effect of over-wintered broad beans, all is not lost. In this case, it simply puts the plant back a bit. kill the black fly, and the plant soon recovers.
There are three basic ways of dealing with a Black Fly infestation. Spray with an insecticide or puffer; using a biological control; or preventing them in the first place!"

And regarding getting rid of them:

"The quickest way to get rid of Blackfly is to apply a spray as soon as you see the infestation. This will most certainly be on Broad Beans firstly, followed by French and Runner Beans, then ornamentals such as Dahlias, Poppies and nasturtium later. Later still, they will surface on the Autumnal foliage of Mock Orange (Philadelphus). Viburnum opulus types and Euonymus europus (The evergreen one).

• Natural Predators - exist for most garden pests, but our methods of gardening usually keeps these predators away or - worse still - kills the friendly predators off. The Ladybird in particular is an avid feeder on most Aphids - as are the larvae, which most would wrongly recognise as a pest! The rather beautiful Lacewing is another gobbler of Aphids, and much can, and should be done, to persuade Lacewings and Ladybirds to set up home in our garden.
• Natural Sprays for Killing Blackfly will include those based upon Pyrethrum or Horticultural Soap. These are not the most effective control for getting rid of Blackfly - but they are considered as being 'organic'!
• Contact Spray of BlackFly include Bayer Sprayday (Deltamethrin). Used directly at the clusters of Blackfly - or other Aphids.
• Systemic Control of Blackfly - is absorbed into the plant tissue and sap, and is therefore very effective at killing off Black Fly and other Aphids over a period of time. Scotts Bug Clear Ultra is fine but MUST NOT BE USED FOR EDIBLE CROPS!
• Edible Crops and Blackfly. Bayer Provado ultimate Bug Killer is suitable for most ornamental, and a wide range of edible crops. READ the instructions on the pack to see which edible crops can be treated. The old favourite of Permethrin is not now allowed for use.
• Overwintered Eggs of Blackfly can be attacked with a general purpose oil based winter wash. Winter Tar wash is no longer applicable!
• Biological Control - is comparatively expensive, but effective - if you can create the right conditions. The main problem being that there will be a time lag between being able to source the biological control of Blackfly. Together with this, there will need to be enough Blackfly for the biological predators to act upon."

Sorry for the long post, I am apparently not allowed to post the link to this article!

Good luck,
Jeff