You can either give a smaller piece (such as a sprig or two) every day, or you could give a larger portion 2-3 times a week. Another option is that you could save it for treats as a “reward” for your rabbit! Since he is young, make sure to watch to see that your rabbit doesn’t have any trouble eating it!

The House Rabbit Society states,

What quantities of food should I feed young adults? (7 months to 1 year)

• introduce timothy hay, grass hay, oat hay, and other hays; decrease alfalfa
• decrease pellets to 1/2 cup per 6 lbs. body weight
• increase daily vegetables gradually; make sure your rabbit can tolerate
• fruit daily ration no more than 1 oz. to 2 oz. per 6 lbs. body weight (because of calories)

I would say to use your best judgment. See how your bunny does! 🙂

I agree the safe veg lists online are very confusing. One thing my vet told me is that generally if it is safe for a horse to eat, it is safe for a rabbit and I found the info was easier to find (this may be helpful too if he ever eats a plant he shouldn’t). The rabbit society is pretty good though and you have the bonus of it going more in depth for those veg which are safe but may be high in things your bun should get in smaller quantities, such as calcium or oxalic acid. For those as @jerseybunnies said a sprig or two a day or larger a 2 or 3 times a week is generally good (some buns don’t tolerate certain things so that always takes precedence). I just play it safe by rotating most of my buns greens and most of his greens for any day being from the Leafy Greens II (low in oxalic acid) list, it helps them get more balanced vitamins and such as well. If you are introducing a green do one new one and monitor for a few days to see how it goes, which it sounds like you are doing already 🙂 .

Here’s a full list with high oxalate veggies (group I) for future reference: https://binkybunny.com/bunnyinfo/veggie-list/

In general, a high oxalate veg shouldn’t be more than 30% of the daily veg, and rotate the one you feed each week.

The commonly fed veggies that are high oxalate are parsley, chard, beet greens, spinach.

@Ert000 for a young bun just introduce slowly so you can see if any give him issue. If it’s only one it’s okay 🙂

I do 3 or more leafy greens & herbs a day, and then rotate so he gets at least 9 different ones a week. But my bunny is currently on a no pellet diet and this is what my vet recommends, he is all for trying to feed them what they would eat on their own in the wild. I also like foraging and in the spring and summer there are lots of wild plants to pick where I live. At my local shelter the bunnies get mainly romaine and carrot tops as they get those donated and the bunnies are healthy and happy. Sometimes they get some other lettuces or parsley and they do get pellets too. So how much variety you give depends on what works best for you and your bun! If you give pellets they will have a good amount of vitamins your bunny should need.

The House Rabbit Society suggests 1 cup of veg per 2 pounds of bunny (2 pounds is roughly 1 kilo and one cup is almost 2.5 deciliters).

So you can probably give your bun more vegetables, but you should increase the amount slowly so his tummy doesnt get a shock.

Here is a link to what the House Rabbit Society says about vegetables for rabbits:

https://rabbit.org/suggested-vegetables-and-fruits-for-a-rabbit-diet/