Answer: Crabapple trees are usually grafted rather than started from cuttings, but you can certainly try it. Rhododendrons should be relatively easy to start from cuttings however. Here are some general instructions on taking cuttings (includes crabapple and rhododendron), and also some specifically for rhododendrons. You may need to cut and paste the complete url into your rbowser to make it work correctly.
Good luck with your project!
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