Fressia leaves can go brown and die off after flowering, when they die back dry corms and store for next year. (Little bit of info:) Fressias like to be planted close about 6 in a 5" pot.

Oh dear - they seem to have missed a stage then, not got as far as flowering. Thanks for your reply :)

Scorched by the sun maybe?? Being too close to the window. Or too cold at night time

some of mine did this in the grrenhouse, after they got too hot. they are throwing up flowers so dont give up hope let. :o)

Thanks for the replies - they are at the back of the greenhouse close to the glass, and it got to 32 degrees in there a couple of weeks ago before I damped down (despite shading and vents open on full - so your thoughts must be right.
Thanks Seaburn I'll keep my fingers crossed