They "can" root, easy is relative. Set up right, there's not much to actually do, which makes them "easy". The larger the diameter the lower the success rate of rooting. If you can hang an air layer without damaging the source plant, I would go that route for at least one cutting. I used to root autumn cuttings of shimpaku all the time. I'd just stick them into a flat that was kept in bright shade outside, all winter. Usually about half would root. No hormones, no tenting, just very bright indirect shade. Mix was my blueberry mix. The junipers got struck in with the blueberry cuttings. Bark, peat, perlite and hort grade charcoal, all top dressed with a tablespoon of powdered lime sulfur. Water was 225 ppm, 180 mg/lit as calcium carbonate municipal tap water. Which is medium hardness and the 180 mg/liter of total alkalinity means the pH buffer capacity was not an issue.
Juniper cuttings typically root "right away" when struck anytime in spring through early to middle summer. But it is not unheard of for some cuttings to take longer. I have had some juniper not root until the following summer after being struck. Just leave them outdoors, in the flat, so they get a nice cold winter's rest. they will root when they get around to it. Typically you will see long new growths, that will be the sign you have new roots. Give them 2 years, they may root much quicker, as long as they are still green, they still can root.
