Soaking - Timing

Many of us soak our seeds in H2O2 and/or enzymes prior to stratification. It seems to me, a logical time to soak in enzymes would be after stratification when the embryo is most likely trying to push out of the hard shell.

This could be the reason that several have noted an increased germination after doing an H2O2 soak when seeds have become moldy, and personally, I’ve noted a definite germination increase after soaking in Oxyclean to slow down voracious molds that are killing the seeds.

Anyone have any thoughts on this?


My question (and worry) would be that the enzymes could damage a sprout that was about to germinate anyway if you soaked later on. But then, I don’t have the number of seeds to risk losing a plant to test and see what happens.


That’s a good point, Jaime, and I guess one would need to look carefully at the seeds before soaking. Since I do have the seeds to risk this year (I’ll probably end up with around 12,000)I’ll give it a try.

Has anyone done a control study to determine the actual effects of these soaks? A comparison between two seed lots of the same cross would be useful, one soaked and one not. Anyone?


I haven’t, and based on just a ‘sense’ I didn’t notice a difference in germination, however, the seeds definitely look cleaner after the bromelain soak, and cleaner seeds do have fewer mold problems. Whether that translates to anything beneficial, I can’t say.


I have found over ten years work that since so many things affect germination rates, that you really have to do a control study to determine efficacy of new treatments. A variety that germinated poorly for three years suddenly becomes extremely easy to germinate, for example. Nothing in my technique changed, and yet the rates went from 15% to 95% Sometimes the inverse happens as well, for reasons unknown. I’m sure age and health of the parent plant makes a difference, and I suspect the kind of Summer experienced plays a role to a degree. The pollen parent used certainly has an effect on germinability of the seed.

If you have a cross for which you have a large amount of seed, may I suggest that you divide the seed lot in half and try the soak only on one half? That way, we could know more certainly whether or not this is the variable that caused the increase. I, for one, would certainly like to know. :slight_smile:


Boy do I ever agree with you, Paul! So often factors influence outcomes that we are unaware of, and being human, we are always looking for connections, sometimes inaccurately assigning cause and effect. That then gets passed down teacher to student and … well, you know how it goes. Superstitions are born that way, too.

Anyway, I’ll divide one of my batches in half and soak one and not the other and see what happens. I already have a few ‘experiments’ going with cleaned vs not-cleaned vs oxyclean soaked batches.


Excellent idea Judith. I look forward to hearing about your results.

I am going to try a little experiment too. I have some seeds from a rose called Butterball which is a hybrid of R. spinosissima altaica that have not germinated. Its been a little over a year and I am wondering if I can force them a little bit. Going to soak half of them in oxyclean.

Regarding Oxyclean, Steve, I have found that 1) it does soften the seed coat which may help germination, but obviously does nothing if the embryos are already dead, and 2) slows down or eliminates some molds, definitely more than H2O2, but not ALL molds, once they have started growing. I have only used Oxy on older moldy seeds as yet, and do not have a sense as to how it does with less moldy, healtier seeds.

Looking forward to your results.

I do not believe that soking or the timing of it makes one scrap of difference, it is the mold its self that protects the seedling , it is natures way .

why try to improve on nature , mold is natures prosses of breaking down the hip and protecting the seed till regrowth starts with the new season . dont soke , just plant , Bill .

The original enzyme paper was published in a reviewed scientific journal (Hortscience). I was able to duplicate their results. We both ran controls.

If you have chlorine/floride treated water, you may have to utilize distilled water as enzymes may be sensitive to the chlorine/floride.


Regarding when to soak. I agree with Jamie that using a cellulase (paper disolving) type soak after stratification may damage the sprout. However, my experiments indicate that Bromelain does not have such an effect. I now germinate in Petri dishes that contain a Bromelain solution wetted sand. The seeds sit on the top of the sand.

After being removed from the hips, the seeds were given a 2 day soak in either an organic drain cleaner type enzyme solution or a Bromelain solution.