I seem to have imported a snapdragon disease into my garden a few
years ago. I bought some rather sickly end of season seedlings as
fillers. They failed to thrive and since then no snapdragon has. What
happens is that the leaves start to look thready and get a grey/brown
tinge, new leaves grow in a thinner shape than normal and the plants
slowly expire. I tried to eliminate the problem by not growing or
allowing any to grow for three years. I palnted some nice healthy
specimins this year, the first fklush of flowers were fine but the
plaants are now all daed or dying. Any suggestions as to what this is
and what I can do about it?