pepperhead212
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Using GA-3 to help seed germination

GA-3, short for Gibberellic Acid-3, is a plant hormone, often used to stimulate seed germination. I experimented with it last year, and found that it definitely quickened germination of some seeds, but when I checked tomatoes, peppers, and eggplants, the seeds were actually slowed down, compared to water, and saltpeter (the usual solution I soak them in). However, upon researching GA-3, I learned that some seeds can be speeded up by one concentration, but prevented from germinating by higher concentrations, and I was only testing 500 ppm at the time.

The herbs I tested - parsley, dill, basil - definitely speeded up, esp. the parsley. It also seemed to work well on okra seeds.

Just last week I tried GA-3 on something that hadn't sprouted for me at all, in over 2 weeks - Japanese Spinach. Spinach is notorious for bad germination, and this batch was 2 years old! I also tried it on 2 alliums about a week earlier- also 2 years old, and notorious for not storing well. I put about 6 layers of paper towel in some petri dishes, then soaked these with some 1,000 ppm GA-3. Then I put some seeds of spring onions, garlic chives, and the Japanese spinach on top of the soaked PT, and put the tops on. In less than 48 hrs more than half of the chives, and a generous amount of those spinach leaves germinated! Not as many spring onions, but a bunch more eventually germinated.

Here's the dish of the chive seeds, after about a dozen sprouted ones had been planted. You can still see a few sprouts, and even more the next day.
ImageSprouting garlic chive seeds with GA3 10-17 by pepperhead212, on Flickr

Chives popping up a few days later:
ImageGarlic chives, 10-23, started on 10-15 with GA-3 by pepperhead212, on Flickr

ImageJapanese spinach seeds, germinated in less than 48 hrs, using 1,000 ppm of GA-3. by pepperhead212, on Flickr

Also trying GA-3 on a seed of a curry tree. I put one in a Jiffy-pellet about 2 weeks ago, with no results.
ImageCurry tree seed, removed from the fruit, ready to try to sprout 10-21 by pepperhead212, on Flickr

I'll experiment with other seeds in the off-season. And different concentrations, using the same seeds. I'll keep posted.

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applestar
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This is REALLY interesting! :-()

imafan26
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It is interesting. I have sprouted horenso and chives and murraya koenegii without using any hormones. Horenso is fussy about when I grow it. These seeds take a little longer to sprout normally but will sprout faster if they are soaked overnight in water. However, it does sound interesting if the seeds can sprout even faster. Except the curry seed,for me it is a weed.

pepperhead212
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My garlic chives are the weed here! I stopped growing them outside on purpose, as they choked out everything else in the herb bed; regular chives spread slowly, but I never see them popping up all over, from the seeds, like garlic chives. I leave several clumps behind my shed, and harvest from those - next season, I'll harvest some of the seeds from those, to grow indoors. I won't need GA-3 for new ones!

I will only be using this for old or slow seeds. Things like parsley, FI, or something I had no results with, like that Japanese spinach. I'll test some things I had negative results with, like the peppers, but different concentrations, and see if there is any improvement. I have a bunch of seeds for varieties I'll never grow again, but I could use for these tests.

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TomatoNut95
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I find soaking hard-coated seeds like Morning Glory seeds work just fine. Before heading for bed I place the seeds to plant in water and by next morning they are swollen and ready to plant. I've never heard of this GA-3. Is it an all natural based hormone like the blossom spray? I prefer seeing if the seed(s) come up on their own. When they do, I begin administering light does of Miracle-Gro and sometimes smelly fish emulsion.

pepperhead212
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I don't use this for a lot of things - just seeds that are slow to germinate, or not at all. Here's where I first learned about it, and there's a lot of info about it:
https://www.seedman.com/sstartga.htm

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TomatoNut95
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Interesting! So I probably wouldn't use it anyway since I hardly use slow to germinate seeds like onions and carrots, but I appreciate learning about it! :)

pepperhead212
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Here is the testing on those eggplant seeds I posted a while back - something I didn't test back the first time I tested it (maybe I didn't have any trash seeds for EP). I had two types I wanted to test. First, some Neon seeds, which I saved some of last season, despite being a hybrid, only because the variety disappeared from all of the catalogs. And some Hari, which is my most productive variety, but it didn't germinate at all last year, despite only being 2 seasons old. So I wanted to see if the neon was viable, and if I would have to order more of the hari.

I soaked 7 or 8 seeds of each, some in the GA-3 solution, the others in a saltpeter solution (I would have done a control group in just water, but I didn't want to use that many more seeds). I was shocked when the GA-3 Hari seeds began to sprout in less than 48 hours, and every seed had sprouted in just 5 days! And still, after 2 weeks, none of the saltpeter Hari seeds has germinated (actually, I just saw one sprouted in that tray, 15 days after started). The GA-3 Neons were not as fast, but a couple sprouted, and a couple more in the Neon saltpeter dish sprouted a few days later.
ImageGA-3 treated Hari seeds, starting to germinate in 2 days, all germinated in 5 days. by pepperhead212, on Flickr

ImageGA-3 Hari seeds, all growing, after 10 days. by pepperhead212, on Flickr

ImageA couple sprouted GA-3 treated Neon seeds. by pepperhead212, on Flickr

ImageOne saltpeter treated Neon seeds sprouting, 1-24 by pepperhead212, on Flickr

imafan26
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I don't use much hormones on seeds or plants. I don't have trouble germinating the solanacious family as long as I get the temperature right. At least 50 F. for tomatoes, Peppers and eggplant usually germinate best at 68-80 F. The bell peppers can germinate at the lower end of the range, but Peppers from India and hot climates germinate better when it is warmer and days are longer.

Super Thrive, Eleanor's VF11, and Ortho B1 root stimulator enhance hormones. I usually, don't use any of them for seed starting. I have used them for transplanting and soaking plants before before repotting. Soaking most seeds in warm water overnight speeds germination too. Call me superstitious, but I do plant by the moon calendar and plant flowering and fruit plants when the moon is waxing and root plants when the moon is waning. I usually will not plant anything in the last week of the month. Certain seeds germinate in its own time Nasturtiums and some herbs will only germinate when conditions are right for them. Ginger and turmeric will bloom and go down at the end of the year (Sept-Nov) and turmeric will start growing fairly soon, but ginger usually waits until April to sprout again. Some of the solanaceous family does do better with salt peter and when the temperatures are between 70-80 degrees F.

Dilution does matter. I usually only use 1 drop super thrive per gallon of water to boost plant growth and flowering. It can only be done once a year and the plants must be healthy and have adequate soil space and nutrition, otherwise super thrive will force the plant to grow and it will exhaust itself. Dilution rates for node stimulation on orchids and other plants are 1 part super thrive to 9 parts water. The resulting solution (we usually store it in a medicine bottle. It needs a dark bottle to protect it from light.). The solution is applied with a cotton swab to the nodes to induce root or keiki. It needs to be handled with care. Usually, I wear a double pair of gloves. More and using more often can kill the plants instead.

pepperhead212
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@imafan I usually keep eggplant seeds at 80°, peppers around 85°, though most of the peppers I grow are tropical, and chinense peppers are especially speeded up by the higher temps. I only use the GA-3 when I have trouble with seeds, which is why I tried these, before the time actually comes, to plant them for the garden. I also tried some really old radish seeds, that I can't find anywhere, but I couldn't get any of those to sprout. I was really surprised that it worked so well on the EP, since it had a negative effect on tomatoes and peppers.

pepperhead212
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I put two more seeds in dishes with the GA-3 today - Hoja Santa and Mexican Oregano. The Hoja Santa is small, but the Oregano even smaller - I got them out of dried flowers in some Mexican Oregano I got recently, using an eye loupe and tweezers. I got one to germinate in a Jiffy pellet a while back, but it just wouldn't grow. I'll see how these do. The hoja santa was from 2016, and when I grew it then, the plants got huge.

imafan26
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Radish should sprout readily. Seeds don't keep forever. Cold or frozen seed keeps the longest, but all seeds lose viability over time. Heat, humidity, moisture, and variable storage temperatures can shorten the life of seeds.

Some seeds don't last long. Corn and zucchini seeds lose viability quickly. Beans and dill seeds are good for 10 years. Most seeds are good for 3-5 years if properly stored.

https://www.highmowingseeds.com/blog/se ... ity-chart/

I think your radish seeds were probably too old.
If you are using hormones to stimulate growth, you need to pay attention to the dilution. Different types of cuttings and seeds need different dilution rates.



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