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Phoenix Az

How hot can I make a seed while germinating and still not kill it? And would it be a benifit to heat the seed to high temps (95 F). In I measured the soil temperature and it was 95-96 F in the day. I was thinking mabey if I started the seed in hot temps it would harden it.

6/16/2004 5:03:51 PM

[email protected]

I have no data to support this, but when I've germinated seeds above 90F, I've had more issues with damping off (Pythium). This spring I kept the heating pad between 85-88F & got better results. A little slower than 90, but lower mortality. Temps above 100 seem universaly fatal for most people I've asked.

6/16/2004 5:35:40 PM

Phoenix, AZ

There is much research to support heating seeds.

At the initial point of germination, heat will "wake up" the seed if done for just an hour or so. What you don't want to do is keep them constantly at extreme temps.

Later during the germination process, higher temps (95-105) for up to an hour will initiate "heat shock proteins" which will harden the plants. However, continual exposure will damage them. I have successfully germinated pumpkins that were germinated at 95+ F continual but were very stunted.

I have a huge list saved under my favorites regarding this subject because it is so critical to us here in AZ. I also did multiple tests on pumpkin seeds myself.

Here are some more interesting ones:

http://www.csrl.ars.usda.gov/PSWC/research/hot.html

http://www.blackwell-synergy.com/links/doi/10.1046/j.1365-3040.1997.d01-33.x

http://www.publish.csiro.au/nid/102/paper/PP96118.htm

http://genetics.biol.ttu.edu/signal/larkindale02.pdf

Many that I saved have to do with decreasing the damage done by high temps with simple things as calcium and salicylic acid (aspirin). Word of caution: VERY small amounts should be used.

What I did not find was the effect this "heat stress" would have upon our ultimate goal of generating large fruit. Most studies did not go that far or were not specific to fruit-bearing plants.

If you need more references, I have plenty for you to study.

Ben

6/17/2004 1:09:51 AM

Wichita, KS

wow. cool stuff.

6/17/2004 1:18:40 AM

valparaiso, in

this is my first year growing AG, but i will share my results on my germinating. my first 8 seeds came from a pack bought at a store in Canada. after 3 days on the heat pad with no results i checked the temp. i was at 103 degrees. i guess i cooked them. threw those ones out and started again. this time i used seeds that were sent to me. i kept the temperature around 87 degrees and all 4 of them germinated within 3 days. i have a bunch of junk seeds that were sent to me, and i will try to perfect my technique over the winter.

6/17/2004 3:06:58 AM

Phoenix Az

Thanks hot pumopkin

6/18/2004 2:42:47 PM

Ontario, Canada.

My 582 hester suffered heat shock early on as I stupidly left it and the pot on too high a setting. Sadly it never recovered and was history after a short couple of weeks.

6/18/2004 3:56:55 PM