Antirrhinum wilting

After sowing antirrhinum seeds, germinating and growing them on successfully for may years - this year many of them have suddenly wilted.

They were seeds collected from last season (as always), germination was ok (as always) pricked out, potted on, hardened off, protected from all frosts and hot sunny days, watered (as usual), done nothing different at all this year.

There are no signs of pest damage or biological problems what so ever. They have just suddenly wilted.

Never had this problem before!

Any ideas?
Leucojum

 

Oh dear Leucojum, i am 'trying' to grow these but not having much success so far. Sorry i couldn't help.

cheers