Hot and dry in the greenhouse ? this creates the favourite living conditions for the Red spider mite ( or more correctly known as the ‘Two Spotted Mite‘ ) which is actually more of a pale colour with two dark spots on its back – they only turn red in colour when the hibernate in late autumn.
A slow moving mite when compared to its predator ” phytosellius” which is a smaller pear shaped mite that is – weirdly -coral red in colour.
The speckling above is one of the first signs and a call to action . At this stage the problem can be cured using predators available by post or with an organic spray such as ‘Plant Invigorator‘ .
When the cobwebs above start to appear you may be too late for a simple remedy and sacrificial pruning may be the only way forward.
These cobwebs will cover the tips of young shoots, often bending the tips downwards and almost ‘dripping’ with mites. Your best answer is to prune out all you can and then start regular sprays with an organic spray to wash the plant clean, if it is in a pot remove the plant to the garden and hose it down – Red spider mites do not like getting wet.
Regular seaweed sprays such as ‘Seasol‘ will also help by strengthening the leaves.
There are no chemicals that work effectively for amateur use.
On this under side shot you can see the tiny mites- just !