Question
Hello. I'm in Zone 5 and have access to nice specimens of Oregon Blue Cypress (Chamaecyparis lawsoniana) and Hetzi Columnar juniper (Juniperus chinensis) and would like to propigate them via cuttings if that's possible. I've never tried propigation via cuttings before as I usually grow from seed.

Questions:
When is the best time of year to take cuttings from these plants?
What type of medium is best to grow them in? Coarse sand, Turface, peat moss?
If propigation is successful, how long might it take for these plants to grow root systems?

Thanks.

Answer
Hi John,
Thanx for your question.  I am not an expert at rooting conifers but here is some information I found at USDA that should apply to both species you mention in your inquiry.

Cuttings to be rooted in the greenhouse can be taken at any time during the winter or rooted outdoors on heated beds.  Exposing the stock plants to several hard freezes seems to give better rooting.  Optimum time for taking cuttings is when stock plants have ceased growth (i.e. the late fall-winter propagation period is more successful than summer).  For propagating in an outdoor cold frame, cuttings are taken in late summer or early fall.  There may be advantages to using bottom heat.  Lightly wounding the base of the cuttings is sometimes helpful, and the use of root-promoting chemicals, especially IBA, is beneficial.  Recommendations for root-promoting chemicals include the following: 2500 IBA Quick-dip (Alabama), 3000 ?8000 ppm IBA liquid, and 0.3-4.5 percent IBA talc.  A medium-coarse sand or a 10:1 mixture of perlite and peat moss is a satisfactory rooting medium.  Maintenance of a humid environment without excessive wetting of the cuttings is desirable, as is a relatively high light intensity.  A light, intermittent mist can be used.  Bottom heat of 60-65癋 (12癈) is critical the first six weeks of propagation to allow the basal wound of cuttings to callus.

Critical here is that cuttings be taken when the trees go dormant and hard freezes seem to encourage rooting.  I hope this helps.
Tom