Avocados, chocolate, caffeine/alcohol, lactose, apple seeds/cherry pits and similar, dry beans/legumes (sprouted should be ok, cooked even better), garlic (fine in moderation, pigeon racers often infuse water with cloves of garlic and apple cider vinegar), onions and similar, broccoli(I've heard but not 100% sure), highly salty food.
Find out what herbs / flowers / grass / shrubs are toxic to them.
You can probably google this information.
For example, azalea flowers will make them sick so don't put them near an azalea plant.
http://www.theparrotsocietyuk.org/veteri...
http://www.parrot-and-conure-world.com/n...
http://www.theparrotboard.net/Forums/sho...
@ Vernadead Good advice except, Broccoli which safe and a good for them.
Please inform me of what not to feed my companion birds?
