We are after obtaining alot of greenfly in our school greenhouse, especially on our strawberry plants and our apple seedlings. What is the best and safest way to remove them.
You can wash off a lot fo greenfly with a jet of water from a hose or you can use insectides based on fatty acids, such as Organic Pest Control or Doff Greenfly and Blackfly killer.
For the strawberries, wait until fruit is gone. And do not use these sprays on a warm sunny day.