Answer: In my experience, gardenias are normally (and easily) propagated by rooting soft wood cuttings during the summer months; however, if you are intent on grafting, you might wish to look at some of the detailed grafting references listed below. The last is used as a college level text.
Grafting is quite a skill -- perhaps best learned through observation and practice -- good luck with your project!
How to Graft Trees : The Art of Grafting and Budding, by Jack Frost Paperback Spiral edition (January 1991) ISBN:
The Grafter's Handbook by R. J. Garner Paperback 5th Ed edition (March 1993) Cassell Academic; ISBN: 0304342742
The Complete Book of Plant Propagation by Charles W. Heuser (Editor), Richard Bird, Mike Honour, Clive Innes, Jim
Arbury, Mike Salmon Hardcover - 224 pages (September 1997)
Taunton Pr; ISBN: 1561582344
Taylor's Easy Plant Propagation by Nancy J. Ondra, Barbara Ellis Paperback (May 1998)
Houghton Mifflin Co (Pap); ISBN: 0395862957
Plant Propagation : Principles and Practices by Hudson Thomas Hartmann (Contributor), Dale E. Kester, Fred T., Jr. Davies
Hardcover - 912 pages 6th edition (January 1997) Prentice Hall; ISBN: 0132061031
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