Answer: First of all, since the cold is starting to set in, you need a plan to protect your new shrubs this winter. Even though they're all hardy in your growing zone, that's based on the assumption that they're growing right in the ground. The roots of the plant aren't as well insulated in a pot. You'll need to pile straw or other insulating material around the pots, and secure it in place with a tarp. The shrubs may also need some shelter from wind, which is very drying in winter, since the plants don't actively take up moisture during the winter months. A wrap of burlap is probably sufficient.
Both Japanese maple and rhodies are partial-shade lovers, and Burning Bush (Euonymus) prefers full sun, but will certainly grow fine in only part-day sun.
Rhodies need an acidic soil (pH 4.5-6.5) so make sure there's plenty of peat moss in the soil mix. Fertilize with a balanced fertilizer (5-5-5) or special azalea/rhodie food in spring. The others prefer a slightly acidic soil (6.0-6.5) and a light feeding with balanced, slow-release fertilizer in spring. Topdress all pots with fresh compost in spring and each month throughout the growing season.
Keep the soil in the pots evenly moist, and make sure the soil drains well so that roots don't sit in wet soil, since this can invite rot. You may have to water daily - just monitor the soil moisture by touch. Ideally, the soil should feel slightly moist, not wet nor dry.
The only pruning you should have to do is removal of damaged or dead branches. Euonymus may need some trimming to keep its shape. Wait til early spring to prune. Snap off spent rhododendron blossoms with your fingers.
I hope this covers it for you!
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