I can't think of anything particular about pink or orange that would affect seed germination. allthough pink and orange are very weak growers in colder climates. So possibly starting to germinate and then get frost killed before getting above soil. Just a wild guess.
I haven't noticed any similar germination pattern here.
In my post of seeds in pantyhose, the pantyhose is in a salad container, that contains salad when bying it in store. One of these containers contains agout 80 seed pods in plastic baggies with peat moss. I use cookie or treat sized plastic baggies. Whole container can be snuck into fridge without taking up too much space. Have gotten away with tow, but when ther were three, I got banned from family fridge. Then they went into garage untill it starting gettin to freezing temperature, then went under back stairs, where it was at near fridge temperature. Other option is a bar fridge.
From: Betty Wilkerson <Autmirislvr@aol.com>
Sent: Sat, Dec 4, 2010 8:03 am
Subject: [iris-photos]HYB: seed: germination
Each year when I have a lot of seedlings, I get a couple of crosses that only sprout one or two seed (first year) from a cross with 25-50+ seed. Sometimes, I get second year germination from these pots but more often I don't. Since we're using the photo list for this conversation I thought I'd include one of these seedlings--2155-01. No additional seedlings from this one.
There will be a couple of crosses that don't sprout even one seedling. These are most often among the orange or pink.
Any theories on why these seem fragile? Is it the recessive factor or are they just weak lines? Anything I can do to increase the chances of these sprouting, other than refrigeration? I just don't have facilities for refrigeration or raising seedlings in a protected environment.
This crop has been grouped according to the color or pattern, so I should be able to spot any germination patterns that develop.