I know this picture has a lot of veggies in it, I couldn't resist! Really, it's recommended that you start out simple for the first batch in your VeggiDome.
Six celery sticks, rinsed and cut on the ends.
Six carrots whole, rinsed and cut on the ends.
Six leaves of lettuces broken off or still on the head if it's small enough, rinsed.
The maybe put one or two choice vegetables you might have on hand.
The important next step is to eat them. Don't treat it as a still life. Eating at least two veggies out of a VeggiDome per day makes for the best atmosphere/operating conditions. Then week after week see if you can get the Zero waste balance going. If you end up having too many carrots in there for the week, then only put in four or five next time! Eating is personal. Tastes change. Seasons definitely change. Eventually, when you understand your rhythms with veggies better, put in a sample from every vegetable from the fridge, except for food you may only cook, like eggplant or potatoes. It's so cool to see your selections of veggies, every time you walk by the kitchen. Beautiful food? Go ahead, give in to healthy temptation!