The issue of being rootbound will likely be the overriding factor of how well they establish and begin to put out new growth. Ideally, removing as much of the soil as possible from the container planting and gently teasing out the roots should have been done before planting. It might even have been necessary to remove some larger circling roots to encourage outward growth. If this wasn't done, the establishment of the shrubs could be compromised and they could possibly decline and eventually die. Since they were so newly planted, this is something that can still be corrected. And its been well-established that trees and shrubs establish faster and fare better if planted in unamended soil. Laurus nobilis is not very fussy about soil conditions other than needing good drainage. It would have been preferable to have amended the entire planting area (ideally, the expected mature root spread) rather than individual planting holes. If you do dig them up to attend to the roots, make sure the amended planting holes are expanded as well to distribute the amendments over the largest possible area. Other than attending to any root issues, I wouldn't do anything else at this time. Stressed plants (being rootbound, the hail damage) do not benefit from being fertilized, so just keep them properly watered. If the chlorosis continues, you could apply some chelated iron according to product directions. When the plants start pushing some healthy new growth, you can prune them to shape and to encourage new growth - bay laurels are often grown as container plants and topiaries and respond well to pruning by generating a dense form and lots of foliage. If you mulch with compost (preferable to incorporating into the planting hole), these plants may require no further fertilizing. Or apply an appropriate amount of an organic all-purpose fertilizer in late summer or early fall - I recommend organic because it is less likely to be over-applied, won't leach into groundwater and will encourage a healthy soil.

Assuming the plants are still very small with only a few leaves you could probably just give them a good wash in the sink. If you put your hand over the soil you can wash each leaf and stem by rubbing between your finger and thumb with luke warm water and a smidgeon of soap. Then rinse. May be a two person job. I'm a great believer in washing plants before reaching for more expensive solutions. There is no need to destroy leaves just because they have a bug or two. Disease is a different story. Bay is perfect for washing because it has tough glossy leaves which youcan clean thoroughly. Regarding fungus gnats. They like damp soil so maybe you are keeping your baby bays too wet. It is winter and they would not be growing actively in their natural habitat. Just sitting it out til spring. Another tip is to get them outdoors as often as possible if the temperature is suitable. (Bays here cope with temps around freezing quite happily and can manage down to about -5c occasionally.)

I've had one in an even larger pot than that, 18 or 20 inches, for many years. I move it out after last frost and in before first frost. I keep it fairly well cut back, and get all the bay leaves we could ever use in a year with one plant, and we actually use quite a lot (my wife is Russian, makes lots of soups, and even uses them cooking noodles and things). The main base is maybe 3 to 4-inches across. I use a good potting mix, and each spring I consider whether it sits high enough in the pot, dumping out the whole thing, adding fresh potting soil in the bottom of the pot, replacing the main mass, then filling in around the edges with fresh potting soil to be no more than about an inch below the lip of the pot. Remember that this is a tree, or at least a significant bush. Don't restrict it too much. A smaller pot may work for a year or so, but if you want it to go for the long haul, may require a larger pot. I also keep a yerba mate tree in a pot the same way, as well as multiple lemon verbena and stevia bushes that don't hold up well to winter and need to be moved in.

nice, very boho. i do not usually do paint.