seed germination info needed

[Robert K]

i am looking for any documents or websites that anybody have in regards to cactus seed germination (any types) mainly on commercial scale. this include steps of sowing conditions etc. british sites preferred. also if anyone has information they have themselvers which i can look at that would also be very helpfull. so any information on cactus seed germination such as expereiments research and figures as well as guides will be much gratefull. many thanks

[Chris43]

Hi Robert,
I am no commercial grower, but have been keeping records of my seed growing over the last 3 years (2006, 2007 and 2008).

I have only sown single packets of seed, typically 10-20 seeds depending on species and seed source. In all, I've probably sown some 300 species, from a variety of seed sellers.

My technique has been for each of these three years the same, which I can detail if you would like me to - basically nothing special, using the baggy method.

You are very welcome to my spreadsheets if you'd like them. If you do, I'll email them to your email address given in your profile here.

Best wishes,
Chris

[Robert K]

Chris43 Wrote:
-------------------------------------------------------
> Hi Robert,
> I am no commercial grower, but have been keeping
> records of my seed growing over the last 3 years
> (2006, 2007 and 2008).
>
> I have only sown single packets of seed, typically
> 10-20 seeds depending on species and seed source.
> In all, I've probably sown some 300 species, from
> a variety of seed sellers.
>
> My technique has been for each of these three
> years the same, which I can detail if you would
> like me to - basically nothing special, using the
> baggy method.
>
> You are very welcome to my spreadsheets if you'd
> like them. If you do, I'll email them to your
> email address given in your profile here.
>
> Best wishes,
> Chris


yes if you send me them with your methods that would be great thankyou

[Bill]

RObert

Mesa Seeds website while not UK has quite a bit of detail on conditions for many plants which would be appropriate wherever you are.

http://www.mesagarden.com/

[Nick]

Doug Rowland does an inexpensive booklet, but you could prbably find as much Googling

[DaveW]

You might try e-mailing Brian Fearn at Abbey Brook, since he did an article in either the BCSS or NCSS Journal on ideal seed germination temperatures using something called gradient bars at his universities laboratory when a student. I don't have a complete BCSS/NCSS index to look up his article and re-find it, but no doubt he can give you the reference, or photocopy.

If I remember correctly the optimum soil temperature they found for germinating most cactus seed was 23 Centigrade (= 73 Fahrenheit)

However, I don't think they did any tests on whether fluctuating day and night temperatures altered or improved germination as is often claimed.

That might be an interesting experiment if anybody has enough seed of the same species. Subject one batch to a constant germination temperature day and night, but for the next batch switch off the propagator during the night to provide the normal high daytime and low night time temperatures they get in habitat. A simple cheap timer on the propagator plug socket would switch it off overnight and back on during the day.

I don't use a propagator anymore, just stick seeds in the greenhouse so they automatically get high daytime temperatures and low night time ones anyway.

DaveW

[Mal H]

Robert, you might find this link to a BCSS article by David Quail useful:

http://www.living-rocks.com/quail2.htm


[quote=Dave W]If I remember correctly the optimum soil temperature they found for germinating most cactus seed was 23 Centigrade (= 73 Fahrenheit)

However, I don't think they did any tests on whether fluctuating day and night temperatures altered or improved germination as is often claimed.
[/quote]

Yes, according to the Journal of Arid Environments article 'Cactus seed germination: a review' by Rojas-Arechiga and Vazquez-Yanes, temperature extremes in general do not promote germination (i.e. 28 degrees C) and 20 +/-2 degrees C gives good germination in a wide range of cactus genera.

As might be expected, species vary in their responses but generally a higher temperature reduces germination time. The response to temperature also changes as the seed gets older (they cite a lower optimum temp. for 1 year old Parodia crysacanthion seeds compared to 7 year old seeds.

Interestingly, most studies have failed to demonstrate that temperature fluctuations promote better germination of many species and may actually be unfavourable. However, I can't determine if these fluctuations were ever tested with a warm day, cool night cycle as you suggest DaveW, so this would indeed be an interesting experiment for us all if you choose to try it Robert.

I personally found that the propagator I used was too warm and previously got lousy germination, so this year I too ditched using a propagator until I can afford a decent one.

Mal.

[iann]

I try to avoid large temperature variation during the germination phase. Some species don't do well with it.

Others don't seem to mind. Recent tests on Epithelantha and Avonia seed gave great germination with daytime highs around 30C (maybe higher since the pots are covered) and lows below 10C.

[DaveW]

You really need a soil thermometer to test the seed pan soil temperature (available from many garden centres) since Fearn's experiment was the temperature the seed was in contact with, not air temperature. The experiment was done with seed on metal thermal gradient bars with the seed scattered on damp filter paper as I recall.

The thermal gradient bars are a metal bar heated at one end and refrigerated, or cooled at the other end, thus giving a progressive range of temperatures along it's length. The optimum germination point for the seed scattered along its length was then tested and the temperature read off.

DaveW

[Robert K]

in terms of eqiment should not be a problem however keeping same temperature may be as it is in a very large glasshouse where the experiment will probally take place