In my early years in the Society, I heard about seeds of Grevillea being successfully germinated in plastic bags and decided to give it a try.

My method was to place three handsful of peatmoss in a clear plastic bag (267 x 381 mm), add approximately half a cup of water, then a quantity of the required seed and shake the lot together to mix (rather like flouring chops for cooking). Then I blew into the bag to expand it and secured the neck with a twist-tie.

The bag was then labelled with the species name and date of sowing, and attached to the clothesline under my house by the twist-tie. This was in a position where there was plenty of light, but no direct sunlight.

Two bags were filled in that way and attached to the clothesline. They were inspected every day or two. With clear plastic bags the first shoots and roots can be seen as they form. As soon as they showed, I potted them into 75 mm tubes of a sand-peatmoss (3 to 1) mix for growing on. Some plants damped off, but this can usually be prevented by spraying with a fungicide.

The first seeds I tried were Grevillea pteridifolia (seeds were washed in a strainer under the hot tap for a few minutes) and G. glossadenia (seeds were nicked with a razor blade to expose a little of the white embryo inside). The former germinated in 4 weeks, the latter in 3 weeks. Not all seeds germinated at once.

The bag of G. pteridifolia produced 59 plants over a period of 3 weeks, a much higher percentage than I had anticipated (about 99%). Over a period of 4 weeks, G. glossadenia produced 7 plants from 10 seeds planted.

Inspired by this success, I decided to try other types of seed with the following results:-

SPECIES	FIRST GERMINATION	SUCCESS	TREATMENT
Acacia farnesiana	2 weeks	50%	boiling water
Banksia marginata	2 weeks	90%	none
Banksia spinulosa	6 weeks	50%	none
Barklya syringifolia	4 weeks	50%	boiling water
Cassia odorata	3 weeks	70%	boiling water
Eucalyptus miniata	1 week	50%	none
Eucalyptus setosa	1 week	70%	none
Cupaniopsis newmannii	2 weeks	100%	none
Flindersia australis	2 weeks	90%	none
Grevillea glauca	2 weeks	100%	nicked
Kennedia rubicunda	3 weeks	100%	boiling water
Lambertia formosa	4 weeks	75%	none
Leea indica	8 weeks	100%	none
Omalanthus nutans	1 week	100%	none
Petalostigma triloculare	5 weeks	100%	none
Pittosporum phylliraeoides	3 weeks	70%	none
Planchonella australis	3 weeks	100%	none

These seeds were all planted in September, which seems to be an optimum time for such activity. Whether it is as successful at other times of the year I am not sure. Fine seed, such as some members of the Myrtaceae family, cannot be used, as the seedlings are too fine to handle.