[dchubbuk]

hi every year i have the same problem on my allotment but this year something has laid on my blackcurrant but it's a white blob not unlike marsh mellow with a black cap i have never seen this before and got out my hose to get them off but missed a few i don't like using pesticides if not needed i just give everything a good blast of my hose (it's much better for the plants too! )i would like an encyclopaedia of all insect eggs and their young so i can help the ladybug and get rid of the black&green fly so if anyone has any idea whats on my plants i would be most grateful for a reply 

[Springlands]

Does it look like this - cuckoo-spit. If it is the best way to get rid of it is what you have been doing - just hosing it off. 

http://www.bbc.co.uk/dna/h2g2/A812828

[TheSpartacat]

Without a picture, my guess is a spider egg sac?
Google for images....

[Kleftiwallah]

Sight unseen, I'd go for frog hopper .    Cheers,   Tony.