First, romaine in a 6 in. pot filled with sifted garden compost. Pretty normal. Plant is about 10" high and growing strong.
The second is in half compost and half mushroom. You can see that is is much darker and isn't growing up the way it should. About half the size of the one above. Outer leaves are 5" long.
Now we have pure mushroom in the raised beds. Very dark and stunted. These plants are only about 4" high and leaves are deformed.