The ciriteria for feeding veggies is in moderation and a large variety.
I give my piggies 3 - 4 feeds per day of veggies.,they have a bowl each containing a moderate amount of at least 2 different veg.I do not serve the same veggies at every meal or indeed every day.You do not have to feed the piggies 3 or 4 times a day,a lot of folk only give 2 servings of veggies which is fine as long as the variety is there.
There are very few "bad" foods for piggies and these are normally o.k. anyway if only served occasionaly in small amounts.
Amongs the food I DO NOT give my piggies are:
potato
any variety of beans(this is contraversial tho because some owners do feed them)
iceburg lettuce
avocado pear
spinach
These are the mains ones. It is up to you to research and decide for yourself.There is a lot of feeding info in books and online.
Some of the foods I offer to my piggies are:
spring greens
pointed cabbage
kale
brocoli
parsley
coriander
carrots and tops
cauli leaves
baby corn
corn cobs plus the leaves aand silk
celery
cucumber
romaine lettuce
chicory
chinese leaaves
peppers(red,green and orange)
These are just a few ,look around and experiment.If in doubt,check with someone.
Piggies ,like us,have food preferences ,some will scoff ,say,red pepper,other pigs will refuse it.Also piggies do have food strikes,they may go off a favourite food for a few days for no reason.
80% of the diet should be hay and dried grass,and fresh grass when available.
Your feeding regime is what suits you,and if for any reason you have days when you only have one or two different types of veg available,do not worry,because this will do them no harm as long as they get variety most of the time.