At 13 months they'll just be starting to change over to salads (it's a gradual process in some cases). Offer a salad every day with a nice rotating variety until you come up with some things they like. You can try hand feeding them or moving the salad a bit with your fingers to get their attention. Start offering bugs every other day and then every 3rd day or so by 18 months old. I like to reference this list when I put salads together. http://www.beautifuldragons.com/Nutrition.html
I've had good luck with squash cut into worm shapes, chopped green beans, chopped bell pepper, small amounts of sweet potato, collard and turnip greens. Your dragons may have different preferences though so it will take some trial and error.