Wrapping cuttings has worked best for me in temps between about 60F and 68F. I've had folks try putting them in the refrigerator and all have found they tend to store well, like your produce, without bud break and without callusing. When held at 70F and above, the buds break and they begin attempting to form new canes and foliage. What has appeared to have been one of the most important issues to me is the condition of the material you use for wrapping. The more "dormant" it is, the more resources it contains, the greater the success. Where I've wrapped, that has appeared to have been after "winter" and before the plants have attempted to "break dormancy" and begin pushing new growth and foliage. Once that stage has been reached, the wraps repeatedly failed. Just to confuse the issue, Beth Hanna up in Paradise, California then experienced success in her wraps with commercial florist rose stems in late summer. To further confuse it, Sharon VanEnoo, in Torrance, California, has succeeded wrapping cuttings of polys and hybrid musks (Marie Pavie and Cl. Cecile Brunner from memory, and a few others) almost year round. She has been pumping those out all summer. Obviously, the condition of the material, the conditions under which it is held and its genetics all play parts. What I have repeatedly suggested to everyone is to keep trying, varying a facet each time to determine what is going to work best for them where they are, when they are trying it. If it helps, remember this was originally reported by a commercial, Australian nurseryman who wrapped his Fortuniana cuttings to produce his root stocks. Under my Zone 10a conditions, almost everything (including lilac) I wrapped, succeeded in the late winter through very early spring conditions, held in the temperature range I listed above. Here in my new Zone 9a conditions, it's been quite a bit more hit and miss. Last year, I wrapped nearly four hundred cuttings of all types of roses grown in this part of California. Almost all callused but less than half succeeded. In the more arid, hotter Zone 10a, I planted them in moisture control soil because they would otherwise dry out in a day. The moisture control soil remained too wet here for the temperatures. In Zone 10a, during the period I found most successful, they could experience temps into the eighties after planting out. Here, we were lucky to get into the seventies. In both, I planted them deeply in the individual foam cups I used so only the top one to two inches of the cuttings were exposed to the air and light. As they grew roots and foliage, they hardened off, so once the cup bottoms are full of roots, I can slide the soil balls out, place new soil in their bottoms and replant the soil ball higher in the cups, exposing more of the buried canes. I've never lost any due to their not hardening off well.
California Central Coast
USDA Zone 9b
Sunset Zone 15
Cooler inland coastal valley with strong marine influence