Using Hydrogen Peroxide to Boost Seed Germination

This pandemic has prompted many millions more people to plant gardens this year, and that is really a huge blessing to all.  A self-reliant society is a strong society.  Unfortunately, however, demand has far outstripped seed supply, and people everywhere who were even a little slow to this game are having difficulty finding vegetable seeds.  Many are resorting to using old seeds, some that are even many, many years old.
Whether these old stocks of seed will germinate depends a great deal on how the seeds were stored and the type of seed:  tomatoes remain viable much longer than onions.  (For more information on seed viability, see here.)  If you are looking to plant old seed right now, there isn't much you can do to mitigate factors affecting how the seeds were stored or the type you saved.  However, you can drastically improve your germination rates with this simple tip. 

While this tip is meant specifically for boosting the germination of old seeds, even fresh seeds perform much better using this method.  A study showed that corn seed, which usually has a germination rate of about 70%, boasted a 95% germination rate.  That's significant when every seed counts.

We know that seeds need heat and/or light, water, and oxygen to germinate.  The water has to penetrate the seed coat for the oxygen to get inside the seed and begin its magic.

Some gardeners make it easier for water to penetrate hard seed coats by using some form of mechanical scarification, either by nicking or scraping the seed with a butter knife or using sandpaper (or an emery board) to rough up the surface a bit.  This method works a lot better with squash seeds than carrot seeds.  For the very small seeds, some growers shake seed in a baggie with a little bit of sand to do the same job.  Both of these techniques enable water to penetrate the seed coat faster and hasten germination, but they don't actually boost the amount of oxygen available to the seed.

Hydrogen peroxide scarifies the seed chemically.  It penetrates the old, hard seed coat faster and carries extra oxygen to the interior of the seed, dramatically enhancing the germination rate of even really old seeds.  

There are a few different ways to do this.

The first is to soak the seeds for 30 minutes in an undiluted solution of 3% hydrogen peroxide--straight from the brown bottle in your medicine cabinet.  Rinse, and plant as usual.

The second is to dilute hydrogen peroxide in water and soak the seeds for 18-24 hours, rinse, and plant as usual.  If you go this route, check the weather forecast first to be sure the following day will be good for planting.

3% Hydrogen Peroxide	Tap water
¼ teaspoon	2½ tablespoons
1½ teaspoons	1 cup
1 tablespoon	1 pint
2 tablespoons	1 quart
½ cup	1 gallon

A third method is to put seeds on a paper towel dampened with the solution, roll it up, and put it in a plastic bag in a dry area.  Spray with the solution as the paper towel dries out.  Plant the seeds when they sprout.  

Using hydrogen peroxide to boost seed germination is only effective when there is still some life left in the seed.  If the seed is so old that it is dead, it will not work. 

Links to related posts:
How to Test Vegetable Seeds for Germination

For further information:
https://www.hunker.com/12629366/how-does-hydrogen-peroxide-affect-seed-germination

5.2.22