Ideal Temperature for Germination of Cycad Seeds

[Ice Blue]

I was just curious as to what people have had success with in terms of temperature for germination of cycad seeds. I have read a lot of articles and the recommended temperatures seem to vary from 82-95 degrees. I don't want to cook my seeds but if more heat will speed up germination I'm all for it.

I don't have a super hot greenhouse so I am germinating my seeds indoors on top of the refrigerator. I have some dioon and encephalartos seeds currently sowed in pure perlite in a tray with a 2 inch humidity dome. I have bottom heat and a thermostat. I have set the thermostat to 85 degrees. Several seeds have been popping quite nicely but I would like to get feedback from others as well to see if I can speed up the process. (Yes, I realize that speed up a cycad can be an oxymoron.)

I guess I have a few main questions;

1) At what temperature do you prefer set your thermostat for best results?

2) Do you turn your thermostat off at night to give your seeds a range in temperatures from day to night? (I have heard that a lot of Jubaea growers do this.)

3) Do you use different heating requirements (and thus different trays) for arid, blue South African and Australian cycads (some encephalartos, cycas, macrozamia) as compared to more tropical cycads (Central African encephalartos, zamias, tropical cycas etc.)

Any help or feedback is much appreciated. I don't like using the baggy method, I just have not had good results with it in the past due to fungus.

[cycadjungle]

I was just curious as to what people have had success with in terms of temperature for germination of cycad seeds. I have read a lot of articles and the recommended temperatures seem to vary from 82-95 degrees. I don't want to cook my seeds but if more heat will speed up germination I'm all for it.

I don't have a super hot greenhouse so I am germinating my seeds indoors on top of the refrigerator. I have some dioon and encephalartos seeds currently sowed in pure perlite in a tray with a 2 inch humidity dome. I have bottom heat and a thermostat. I have set the thermostat to 85 degrees. Several seeds have been popping quite nicely but I would like to get feedback from others as well to see if I can speed up the process. (Yes, I realize that speed up a cycad can be an oxymoron.)

You say you don't have a hot greenhouse to grow them in. The greenhouse effect works for small things as well as large things. As an experiment just get a good sized piece of clear plastic and shape it into a square and put it out in the sun, and put a thermometer inside. Even a 2 foot square will get real hot, probably to 135F. Anyway, just thinking out of the box to show you have other options. I don't use electric heating devices for germinating cycad seeds because too many people have had equipment failures and fried 1000s of $s worth of rare seeds.

First of all, I'm sure you already know that if you have a seed that does not have a full sized embryo in it already, you can't speed up germination until that happens. The real answer, and more complicated answer is that it appears as if some cycad seeds will germinate at lower temperatures and some need more heat. The small zamia seeds germinate pretty well once it gets 80 or above. I would say that 85 to 90 would be a good temperature for most of the cycad seeds. The only seeds I have seen a big difference in, has been many of the encephalartos seeds. I don't get good germination from those until the temps outside get into the mid 90s, so that in my greenhouse, it is getting real close to 100F. I would in no way want you to up your heater to 100F, but just note that many of them do seem to want higher temperature for germinating.

A lot of germinating has to do with how the energy in the seed forces the radicle to start growing. It then has to be able to push itself through the hard shell of the seed. On thinner zamia seeds this doesn't seem to be a big deal, but a higher energy and temperature seems to be needed to help push through the encephalartos shell. Look at what people say about germinating Cycas thousii seeds. They say they can take up to 3 year to germinate. The emberyos are full size within 6 months of picking the seeds, but they can take that long, just to push through that very thick shell.

Personally, I have given up using regular methods for germinating my encephalartos seeds. Now, when I know the embryos are full size, I take my Dremel and gring off the spraotuing end of the seed and I can get 100% germination of the GOOD seeds in a week or less, as opposed to waiting an extra year or so for them to pop on their own.

I guess I have a few main questions;

1) At what temperature do you prefer set your thermostat for best results?

2) Do you turn your thermostat off at night to give your seeds a range in temperatures from day to night? (I have heard that a lot of Jubaea growers do this.)

I wouldn't do that.

3) Do you use different heating requirements (and thus different trays) for arid, blue South African and Australian cycads (some encephalartos, cycas, macrozamia) as compared to more tropical cycads (Central African encephalartos, zamias, tropical cycas etc.)

Any help or feedback is much appreciated. I don't like using the baggy method, I just have not had good results with it in the past due to fungus.

The baggie method works great as long as you do two things correctly. You need to open up the baggie every 2 weeks and fluff up the material, get some good air to it and then close it back up. The other is, you don't need to add any moisture at all to the medium.(at least to the medium I am using)Adding any water to the mix, for me, will always make the seeds rot.

[Ice Blue]

Great information. Thank you so much for the help. If it's OK I might PM you with more questions

[cycadjungle]

Great information. Thank you so much for the help. If it's OK I might PM you with more questions

Thats fine, I answer people's questions every day. In case you haven't looked at these, in my article section of my website, I have a couple of germination articles. There may be something in there that might answer some other questions you may have. Tom

http://cycadjungle.8m.com/cycadjungle/articles.html

[Ice Blue]

Holy.....I didn't realize you were Tom Broome! Very cool. I've read a lot of your articles already but thanks for the link so I can get the chance to read more. Will email you for sure with more questions.

Cheers,

Joel