Very, very interesting pieter! Keep me in the loop…. I am always up for learning something new.

debra

Thanks for sharing.

bk

I see it every year, not uncommon in seed growing. mostly when some more vigorous ones touch the top of the wet dome/covering, while others in that flat are too small to handle dry air.

basically the leaves got water logged. cells burst with too much water, they will dry out and look dessicated. if the plant is larger and vigorous new leaves emerge and you can prune the bad ones. really small ones will struggle. give it good air circulation and keep water from pooling on the leaves.

outdoors i have seen it in periods of heavy rain and wet weather. same issue water logged leaves.

Reminds me of Emerald Ruff Cut every single stinking year. LOL

Thought it was time for an update. Thus far neither the Echinacea seedlings or the 'Jaws' I showed with the oedema in the initial pictures have shown any signs of any of the tissue browning, which is a pleasant surprise.

The white spots you see are from a water soluble fertilizer.

What DOES have me surprised is this 'Sunset Grooves'. You can see transparent tissue at the edge of 1.30 and 10.30 position in the picture below and there's also some tissue in the main leaf near the top as well as a couple of other places where you're seeing discolouration as if it was from oedema and I've seen the same behavior on its parent 'Rainforest Sunrise'. The other thing you'll notice is that some of those SG leaves show a distinct white edge which I have also seen on RS and that will eventually disappear as the plant colours up.

Pieter