Potassium nitrate treatment - 0.2 - 0.5% - How long

[CG100]

Statistically too small a sample, but interesting nonetheless.

I have not checked for around a week, but I had no germination in the seeds that I soaked.

In terms of smoke treatment - possibly Garham Duncan, online, suggests burning some light material on top of a pot, though mostly associated with flowering, rather than germination . When I have time and opportunity, I will burn a few dry leaves, straw etc. in something like a can from canned food and then wash the remians into a pot of seeds/bulbs.

[Robert_Parks]

Statistically too small a sample, but interesting nonetheless.

I have not checked for around a week, but I had no germination in the seeds that I soaked.

In terms of smoke treatment - possibly Garham Duncan, online, suggests burning some light material on top of a pot, though mostly associated with flowering, rather than germination . When I have time and opportunity, I will burn a few dry leaves, straw etc. in something like a can from canned food and then wash the remains into a pot of seeds/bulbs.

If you can bear to, burn directly on top of the soil and water it in...obviously advice for getting bulbs to bloom. From observation in the wilderness smoke particulates/ash trigger germination in areas outside the burn area plus provide vast fertilization. In directly burned areas, the accumulated seedbank in the soil surface is triggered to germinate. Some species appear to only germinate from burned soil (fire follower annuals that are never seen except the spring after a fire[1]). Obviously this works best when there is a LOT of seed mixed in the soil.

There are forest floor bulbs that only bloom in the year or few after fires...during the shady years they put a minimal leaf if conditions are good, but the season after a fire they bloom heavily and put up a whole bunch of leaves (probably triggered by smoke chemicals/nutrients soaking into the ground) and will continue to to produce more leaves and bloom some in the years following until they get shaded again. 

[1] With a remarkably profligate growth style, germinate once it starts raining, grow as fast as temperature, light, nutrients allow, bloom wildly and set seed even as the rest of the plant is dessicating, and lots of aggressive seed dispersal mechanisms.

[Martin Bohnet]

Found a study about Hedychium germination that compared KNO3 treatment with Gibberelic Acid, where germination times varied largely depending on the treatment (30 days GA, 40 days KNO3, 50 days untreated), so maybe your experiment isn't over yet.

btw they used 25,30 and 100 mmol/l KNO3 for 24 hours, with the 100 mmol/l being already counter-productive for germination numbers. If I interpret your number correctly, you've used 0.5 weight percent, so 5g/l = 0,049 mol/l ~ 50mmol/l, being well in the useful range for Hedychium.

[CG100]

Molecular weight of pot' nitrate is 101, so 1M (N) solution is 101g per litre - pretty much 10%.

A milli-mol is one, one thousandth of a mol, so a milli-molar solution is 0.01%, as near as makes no difference.

If you hunt for long enough there are lots of reports about KNO3 treatment and "preferred" concentration and soak times vary considerably

[Jan Jeddeloh]

For all you experimental seed sowers I've found something new to play with.  Seeds 'n Such, a US seed company, sell something they call Super Hot Pepper Seed Starter.  It's a mix of Potassium nitrate and gibberellic acid.  Unfortunately they don't tell you anywhere what the concentration is.  I bought it not for hot pepper seed but to play around with on difficult to germinate seed.  I haven't mixed it up yet.  I plan to email and ask them the concentration of Potassium Nitrate and gibberellic acid in the prepared solution.  

Seed will start to roll in soon since I've opened up the SX. Do you folks have suggestions for any seed I should try this brew on?  If I have enough seed donated I don't have qualms about using some for experimentation. I'm not much interested in non-hardy bulbs but I could grow any that germinate for a year or so and then send to the BX. 

Years ago I was trying to germinate seed that required smoke treatment.  My son was about ten at the time.  He was quite willing to take over this part of the seed sowing.  Nothing a ten year old like better than to get to burn something.  Whatever it was didn't germinate anyway.

Jan

[Jan Jeddeloh]

Here's the bag of the packet for the KNO3 and gibberellic acid powder. 

[Lee Poulsen]

Another method, which I did at the time, is to go scoop up a good sized bag of ash right after a big forest fire. I did this as soon as they let us go back into the Angeles National Forest after the 'Station' fire finally burned out in the foothills and mountains behind Pasadena and Glendale back in 2009. I didn't try any scientific method with and without. I just put ash on top of all my seeds I planted that fall from mediterranean climate regions, since I had plenty of it, and as some have pointed out, it is full of plant nutrients anyway. 

[Rick R.]

Jan, maybe if you can get a hold of Viola beckwithii seed, purported to need smoke.

[Martin Bohnet]

One first report from my side: My few Hedychium densiflorum seeds sprouted after about 40 days when treated with 50 mmol/l KNO3, just as predicted in the article I quoted - As there were only very few seeds, I didn't have a control group though.