Citrus Growers Forum

citrange · Posted: Fri 31 Dec, 2010 1:47 pm

I recently came across this summary of scientific tests on the germination of citrus seeds. In general, it confirms that best germination is from fresh seeds at around 30C. Drier seeds germinate erratically over a much longer period.
See http://www2.bioversityinternational.org/publications/Web_version/52/ch49.htm

Sylvain · Posted: Fri 31 Dec, 2010 5:33 pm

I made experiments on Poncirus Trifoliata.
If the seeds are fresh you can use much higher temperatures, like 35 °C or 40°C or even 45 °C and it works even faster. The fastest was one week to germinate.
If the seeds are dry you need to soak them one day or more. Changing the water as soon as it is not clear, until the seeds are "full". However the germination rate is worse than with fresh seeds.
Kept in the fridge they will keep a reasonable germination rate for three month.

Millet · Posted: Fri 31 Dec, 2010 6:35 pm

In the book "The Citrus Industry" on page 56, experiments conducted by Dr. Fawcett of the University of California, show no germination of either Sweet Orange, or Sour Orange seed at temperatures at or above 104 F (40 C). The optimum temperature for seed germination was achieved at 91.5 F (33 C). Simply removing the testa (outer seed coat) also greatly reduces the time required for germination. - Millet (745-)

Sylvain · Posted: Fri 31 Dec, 2010 9:06 pm

Quote:

Simply removing the testa (outer seed coat) also greatly reduces the time required for germination.

Yes, that's what I did when it germinated in a week.

Quote:

no germination of either Sweet Orange, or Sour Orange seed at temperatures at or above 104 F (40 C).

For PT I can say that the fastest was for between 35 and 45 °C in the day and 20 °C in the night.
Every people with a central heating can test it. You just have to dare to put your germinating box on the heater.

brewcider · Posted: Sat 26 Jan, 2013 11:22 pm

my home thermostat is set at 68 degrees and i've been trying to grow some sour orange and flying dragon from seeds. nothing has happened in over 2 weeks. half of my apple seedlings have sprouted though. so i think the temperature is too low for the citrus seeds. instead of going out and buying a heating pad, i placed all the citrus on top of my computer tower which is on 24/7. i checked it and it's 85-90 degrees. that should be perfect. now i just need to wait and see.

skinn30a · Posted: Wed 13 Mar, 2013 5:40 pm

Great info here specific to diffrent cultivars:

http://www.fshs.org/Proceedings/Password%20Protected/1996%20Vol.%20109/132-135%20(ROUSE).pdf

Best,

_________________
Zone: Border of 9a/8b
-----------------------------------------------------
"but do please, Br'er Fox, don't fling me in dat brier-patch"

danero2004 · Posted: Sun 17 Mar, 2013 4:55 am

skinn30a wrote:

Great info here specific to diffrent cultivars:

http://www.fshs.org/Proceedings/Password%20Protected/1996%20Vol.%20109/132-135%20(ROUSE).pdf

Best,

http://goo.gl/4gmua short url

hardyvermont · Posted: Sun 17 Mar, 2013 3:00 pm

http://goo.gl/4gmua short url

Mcafee warns that that is a risky site to visit.

skinn30a · Posted: Sun 17 Mar, 2013 5:07 pm

I've got it in .pdf which I will upload if you can tell me how to do it...

_________________
Zone: Border of 9a/8b
-----------------------------------------------------
"but do please, Br'er Fox, don't fling me in dat brier-patch"

hardyvermont · Posted: Sun 17 Mar, 2013 6:31 pm

Only the short URL from danero2004 gave the warning.

Copy and paste of the original link worked OK.

PDF Viewer did say document may not display properly, it flickered before stabilizing.

Thanks for posting