[whippersnapper]

Already lost one plant because of a very similar looking problem, now a second bigger plant looks like it's heading the same way: leaves are yellow, purple, brown, look very weak and generally less 'green' than the surrounding plants. Is this magnesium def? What confuses me is that plants very nearby look fine?!

What do I do...?!

Any help very much appreciated!

Normal plant:



Problem plant:

[Mitsy]

Cabbage root fly maybe? 

[whippersnapper]

Oh dear...I didn't put any protective discs at the base of the plants...

Is this the most likely cause? Worth me trying anything? Should I protect the existing plants or is it too late (they're getting quite developed!

thanks