Tips for Successful Plant Propagation

Report on Propagation Workshop at Eurobodalla Regional Botanic Gardens, New South Wales on 6 March 2001 - led by John Knight. Report prepared by Mick Donohue.

The following is a list of points John stressed as advisable for success when attempting propagation from stem cuttings, which are the most common type taken.

1. The cutting

• Must be springy, which can be tested by bending the tip back to touch the stem lower down. If the proposed cutting does not spring back upright it is too soft and if it snaps it is too hard.
• The cut should be made at a 45° angle just below a node.
• The cutting should be 5-15cm long depending on the material. Allow for about 4 nodes showing above the medium and 4 nodes buried. Remove leaves from all but the top two nodes.

2. Cleanliness

• Secateurs - must be sharp. Clean with methylated spirits.
• Pots (chlorine).
• Growing medium (microwave if necessary).

3. Ideal temperatures*

• Cuttings 12^oC- 27^oC.
• Growing medium 24^oC - 26^oC.

4. Growing medium

• 3 parts river sand : I part peat moss**, OR
• 3 parts perlite : I part peat moss, OR
• 3 parts vermiculite : 1 part peat moss.

5. pH (acidity or alkalinity) ***

• ''Australian native plants generally prefer a soil that is slightly acid (i.e. pH 5.5 - 7.0)".

6. Hormones

• IAA (indole acetic acid), IBA (indole butyric acid), and NAA (naphthalene-acetic acid) are the compounds most commonly used to promote root growth from cuttings and are mostly purchased in liquid form. The cutting is dipped in the hormone for 5 seconds only and immediately placed in the growing medium.

7. Pots

• Use 80 mm square pots. Insert 16 cuttings in each pot (4 x 4 rows).

8. Propagation Box

• Make one from a polystyrene box with a lid. Cut a large oblong hole in the lid and cover it with clear plastic thus allowing maximum light entry but also keeping the inside of the box moist and humid. Line the bottom of the box with a thick layer of newspaper.

9. Watering

• Keep the cuttings moist and the air inside the box humid by spraying the cuttings a couple of times per day (if necessary).

Please note that John pointed out that these are guidelines only and that no one way is the 'right' way. If something different works for you then that method should be continued.

* Note - at 35^oC plant growth shuts down.

** Coconut peat is best as it is renewable.

*** Taken from "Australian Native Plants" by John Wrigley and Murray Fagg.

From the newsletter of the South East NSW Group of the Australian Plants Society, April 2001.

Australian Plants online - 2006
Association of Societies for Growing Australian Plants