You can use a blender but yes, it does tend to make the pieces very small, often turning it into a mush. For sub adult and adult dragons, coarsely chopping the greens/vegetables is fine. When I prepare salad for my dragon (when I had her, dragonless at the moment but going to remedy that this summer), I cut up enough for a few day's worth of meals. I typically add the fruit fresh each day though as it tends to go bad much faster than greens and vegies.
The blender method is good for hatchling and very young dragons, or for sick/recovering dragons, due to the fact it is easier to digest, being well chopped up to start with. I would leave the bulk of the water in with the mass, but being so finely cut, it doesn't keep in the fridge for very long, so make only enough for one or two meals.
silkworms are a great feeder insect, easy to digest, high water content, high calcium and protein and low phospherous. Though a bit higher in fat than crickets, the fat content is still much lower than other feeder insects (ie wax worms, butterworms, super worms and if given, pinky mice).
I use silkworms for all my insect eating animals, and when I had the bearded dragon, I fed them to her as well. Though at times she did grow tired of them, so offering other insect foods is good, the variety is good and it keeps the dragon interested in her food. Silkworms are great for blue tongue skinks, leopard geckos, crested geckos (and any other insect eating gecko), rats love them as treats, hedgehogs and ferrets can eat them...some turtles as well, sahvanna monitors, etc.
-----
PHLdyPayne