Opinions on the internet vary widely about the benefits and risks of feeding different sorts of veggies to your beardie. There seem to be a few reasons for this, as far as I can tell. Mainly, everyone’s in agreement that you should try to get really high-calcium veggies into your beardie’s diet, with the main exception of spinach. According to more than one site (1, 2), spinach (and, according to another site, also kale)will bind with calcium so, even though it nutritionally contains a lot of calcium, it’s not really all that great for getting calcium into your beardie–in fact it seems to do somewhat the reverse.
There’s an equal number of warnings about iceberg lettuce, for good reason. If you look at a piece of iceberg, you’ll know where they got the name: it’s mostly water. Now, it may seem that something high in water might help your beardie to remain hydrated, but in fact it may make them dehydrated by giving them diarrhea. Also, as mentioned, it’s mostly water, so it contains very little calcium.
The other main point of agreement seems to be that you should try to mix up the greens your beardie eats. One of the easiest ways I’ve found to do this is to use a packaged salad mix. There are definitely bearded dragon owners out there who will no doubt attack this statement, claiming that packaged salad is less fresh and contains more bacteria. To that I would say that I’ll take my chances with a packaged product over the ‘fresh’ greens we often get in my desolate corner of this country, and after all, people can only feel up the un-packaged vegetables and get their grubby bacteria all over them while looking for the ‘best’ one. If you’re a DIY sort of person, though, and you have access to good veggies, you could also try this recipe.
The salad mix I’ve been feeding Squirrel recently is Dole Spring Mix. It doesn’t contain any iceberg lettuce, and the company describes it as a mix of ‘baby lettuces, endive and mustard greens,’ decent staple veggies for beardies, according to the most popular care sheet on the web. Even better, you can make yourself salads with it, and it’s tasty, so that way you’ll be back at the store in two days buying a fresh bag, instead of trying to use an entire bunch of collard greens before they wilt.