- 1). Plan to take cuttings from thuja compacta in winter, when the shrub is dornmant, and in the early morning when its sap is moving the least. Fill medium-sized containers with a moist, soil-less potting mixture and leave them on the counter. Fill a bowl with ice cubes and dampen a few paper towels, and take them outdoors with you.
- 2). Cut several 6-inch, stems from healthy thuja compacta branches. Test branches with your fingers. They should be flexible and light brown, with plenty of foliage. Cut the stems at a 45-degree angle to leave a large surface for soaking up rooting hormone and moisture. Do not cut them straight across.
- 3). Remove foliage from the bottom half of the cuttings. Wrap them in wet paper towels and set them in the bowl of ice. It's important to keep them cold and moist until you can root them. Don't let them stay on ice for more than 1 hour or so.
- 4). Dip the bottom third of the cut ends in rooting hormone, coating the twig and end thoroughly. Tap off the excess. Stick the cuttings in the soilless potting mix until the bottom half of the cutting is covered. Tamp the mixture down around the cutting with your fingers to ensure firm contact.
- 5). Place the containers in clear plastic bags and seal the tops with twist ties. Set them in indirect light, in a warm room. Open and mist cuttings daily with a spray bottle of water, resealing the bag to keep humidity levels high inside. Test the cuttings after four weeks. If they resist a light tug, they are establishing good roots.
- 6). Transplant the cuttings into pots full of regular potting soil after three months, and take them outdoors to acclimate. Transplant into the landscape in late fall.
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