Germination experiment nicking Pasithea caerulea

Sun, 05 Feb 2012 12:50:54 PST
I am interested in what results others have had with their seed germinated from recent BX's. Some have no sign of germination while others were easy.

Here are results from my micro-scale backyard experiment to test whether to nick Pasithea caerulea seeds prior to sowing. More of the nicked seeds emerged earlier, with green shoots at 30 days.

15 seeds were divided into 3 sets. As of today, the number germinated are:
    (A) un-nicked fridge 1 of 5.

    (B) nicked outdoor 5 of 5.

    (C) un-nicked outdoor 1 of 4. (1 lost to mildew before sowing.)

19 Dec 2011 - seeds arrived from PBS BX 299-4 from N. Nguyen.
25 Dec 2011 - started 5 seeds on damp paper in fridge-night/room-day.*

2 Jan 2012 - nicked 5 seeds* and soaked those in one dish and 5 un-nicked seeds in a separate dish.
4 Jan 2012 - sowed 5 nicked and 4 un-nicked directly into bulb box outdoors.*
(I discarded one of the un-nicked seeds because it appeared to have mildew.)

At some un-recorded date between 13-20 Jan,  one seed in fridge dish put out a root-like thing (coleorhiza?). Since it had a brown bottom-edge I thought it was not viable; however, I left it alone. 

25 Jan 2012 - green shoot emerged from that one germinated seed in fridge dish.

26 Jan 2012 - planted that seedling between the two rows of nick/un-nicked seeds, which had not emerged yet. Its shoot was already > 3 mm and root 8 mm long.*…

Then we had some warm days, even reaching 80 F, and some cold nights with frost, and a rain storm. 

1 Feb 2012 - I first noticed P. caerulea sprouts. The nicked row had shoot heights above ground of 0.2, to 1.0 cm while the un-nicked row had one sprout 0.7 cm tall.
4 Feb 2012 - five sprouts in the nicked row and still only one sprout in the un-nicked row.*
5 Feb 2012 - sprouts 1.1 to 1.3 cm tall in the nicked row, only one sprout 1.3 cm in un-nicked row, and fridge sprout 1.5 cm.
5 Feb 2012 - none of the remaining 4 seeds in the fridge-night/room-day dish have sprouted.

* means photographed.…

The easy conclusion is that nicking speeds germination. An alternative conclusion is that the un-nicked batch have mildew. Or, the slate divider shades the nicked row from sun so they remained more moist. With a total sample size of 15 this is hardly real science, but fun nonetheless.

Prior to this experiment, I read here:…
that Pasithea coerulea (spelling at ChileFlora) grows naturally in a climate similar to mine and is "very easy to cultivate". The PBS wiki page explains the difference in spelling.…

- Gastil
Mild Mediterranean 9b/10a Sunset 24+frost, near coast, 34 deg N.

PS: Direct-sowing to non-sterile medium risks damp-off.  (None of my outdoor bulb seeds have had damp-off - yet - so I was unaware of that risk.)

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