He is full of insects, not full of opinions
The commonest reason is sequencing. A dragon offered juicy feeder insects first eats his fill of the food he prefers, then ignores the salad the way a child who has eaten cake ignores dinner. Juveniles get a pass — a growing dragon legitimately needs more protein and may take greens casually. An adult dragon, whose diet should tilt heavily toward vegetables, cannot live on insects without gaining unhealthy weight and missing fibre and calcium. Flip the order: salad goes in first thing, insects come later in the day, and hunger does the persuading that no garnish can.
Still greens do not register as food
Bearded dragons are movement hunters. A bowl of motionless leaves barely registers, which is why hand-wiggling a leaf with tongs, dropping greens piece by piece into view, or scattering them so a few land near the basking spot succeeds where a full bowl fails. Texture matters too: whole tough leaves get one lick and a rejection, while finely chopped or torn greens mixed together are far more likely to be eaten. A few bright pieces — grated butternut squash, diced red or yellow pepper, a shredded dandelion flower — give the salad visual pull, and a whisper of bee pollen dusted over the top is famously persuasive with fussy adults.
Temperature and light quietly set appetite
A dragon whose basking spot runs cool digests slowly and eats reluctantly, and one under a weak or aging UVB tube may lose appetite across the board, greens first. Check the basking surface temperature against the range your dragon's care guidance gives — a basking zone around the high thirties to low forties Celsius suits most adults — and count the months on your UVB bulb, since output fades invisibly. Refusal of everything, not just vegetables, alongside hiding and a darkened beard points at the setup or at health rather than pickiness.
A patient retraining plan
Work in weeks, not days. Week one: salad first, insects reduced slightly for adults and never offered before midday. Week two: finely chopped salad with one proven favourite stirred through, served in two smaller portions so it stays fresh. Week three: widen the rotation — collards, endive, spring greens, rocket, squash — noting which bowls come back empty. Weigh your dragon weekly on a kitchen scale; steady weight while he learns is fine, and the trend line matters more than any single refused bowl. Most healthy adults cave within a fortnight once insects stop arriving first.
When refusal stops being pickiness
Book a vet when vegetable refusal arrives with company: visible weight loss, a tail base that looks thin or bony, sunken eyes, persistent lethargy, runny stools, or a dragon who stops eating insects too. Parasites are a frequent hidden cause in dragons who eat poorly and lose condition, and only a faecal test finds them. For a related question, put a follow-up question to KinsLe's Kinny; he answers using the KinsLe Answers library.