Hi All. I have been growing my own perrenials from seed (usually with success) for many years - however this year I have a real mystery going on. I typically use jiffy pellets to start my seeds and like always, germination has been excellent. I then transplant the seedlings (usually after three to four weeks) into 3" pots and later move outdoors to my greenhouse. However this year, when I take off the clear lids on the trays - my plants go from very vigorous to wilting and obviously distressed in less than 30 minutes! Just the act of uncovering them seems to stress them to the point that nearly 75-80% will die in a single day! What's up with this? I have been doing this for 15 years and the seeds come from a variety of sources - yet it is happening each any every time. I don't think temperature is the issue. It is almost like something in the air is poisoning them - and very quickly. I would really appreciate some input on what could possibly be causing this.