Problems getting spinach seeds to sprout? Try this...

I didn't have time for Kate's method the other day because I had to leave town. But I still wanted to try getting my spinach in before I left, so I tried a fast method: 4-6hour soak in "straight", aka 3%, hydrogen perioxide (this is the concentration I usually see at the store) followed by direct sowing. I double sowed (second seed placed slightly offset from the 9/square pattern) to make up for my expectation that this method wouldn't work as well. I recommend rinsing the seeds off before sowing; I didn't and it was a bit rough on the skin. The method was actually very successful, though I think the 'right' outdoor temperatures and rainfall probably played a role. I even had extras seedlings that I bumped to other squares (the offset allowed me to retrieve them without disturbing the centered seedlings much.)
A nice spinach square, with extras removed:
You can see the bottom center is an offset seedling; the properly spaced seed didn't germinate.

Well done!  Now I have spinach envy. Lost all of my original plantings when I went for hip surgery.  Boy, you miss a couple days of watering and *zap*, that's it. Such fussy little things!
Good to know about the H2O2.   Maybe I'll give spinach another go round.  Altho the daylite hours may be too long here now.

I've never heard of using H2O2 to soak the seeds. When I planted my beans I soaked them in water overnight. They came up in 3-4 days instead of the 8-16 the package said. Soaked my second round of radishes overnight and hey came up much quicker too.

RC3291 wrote:I've never heard of using H2O2 to soak the seeds. When I planted my beans I soaked them in water overnight. They came up in 3-4 days instead of the 8-16 the package said. Soaked my second round of radishes overnight and hey came up much quicker too.

I'm not sure about using hydrogen peroxide on small seeds, nor for beans/peas, at full-strength - I'm using it just for seeds with tough coats. I've used it on squash, cucumber, and okra to good effect, and I plan to use it for nasturtium seeds soon. 
I humidify (i.e. seeds aren't 'underwater') my peas and beans in water with some vitamin C added and sprout them before planting, and soak my cabbage-family seeds, including radishes, for at least 4 hours in water.

OK I didn't realize this was an old thread and went back and read it. The is hydrogen peroxide is just to prevent algae growing. I must have gotten lucky when I started mine. Started them indoors in the covered starter trays just putting one seed in a cell and almost all germinated. Didn't think about soaking them at the time as they were one of the first things I started indoors back in January. I did later read about scarifying them. Realized I didn't start near enough when I transplanted them so about half were direct planted. They caught up with the starters pretty quickly. My thinking is no transplant shock made some difference there. There were a couple that I found when I harvested them after they started bolting that were tiny under the rest and left them in the ground. Now they are starting to grow. I suspect they will bolt pretty quickly but may let them to get the seed.

Not everyone has issues with germinating their spinach seeds; most of my spinach seeds are over a year old so I figured they were likely to need some help (spinach is theoretically more sensitive to aging than the average seed.)

Hydrogen peroxide does prevent algae and pathogens, but it can also directly improve germination of some seeds. Science shows it works, but they are still trying to figure out how/why/when/which. It's believed the peroxide chemically interacts with the coat of seeds, softening it; oxidizes certain germination inhibitors; and sends a germination signal to the seeds.
https://www.hunker.com/12629366/how-does-hydrogen-peroxide-affect-seed-germination
http://journal.frontiersin.org/article/10.3389/fpls.2016.00066/pdf

BeetlesPerSqFt wrote:I didn't have time for Kate's method the other day because I had to leave town. But I still wanted to try getting my spinach in before I left, so I tried a fast method: 4-6hour soak in "straight", aka 3%, hydrogen perioxide (this is the concentration I usually see at the store) followed by direct sowing. I double sowed (second seed placed slightly offset from the 9/square pattern) to make up for my expectation that this method wouldn't work as well. I recommend rinsing the seeds off before sowing; I didn't and it was a bit rough on the skin. The method was actually very successful, though I think the 'right' outdoor temperatures and rainfall probably played a role. I even had extras seedlings that I bumped to other squares (the offset allowed me to retrieve them without disturbing the centered seedlings much.)
A nice spinach square, with extras removed:
You can see the bottom center is an offset seedling; the properly spaced seed didn't germinate.

That turned out great! I'm going to try this next time I do some spinach.

Be warned, I the think seedcorn maggots got one of the squares in the next spinach succession: I dug around and found one of the seeds and gave it a little squeeze and it had tiny white wrigglers in it. Not sure whether I can reseed with some sort of cover to block the flies, or whether the square is now 'contaminated.'  Your method, with the seeds being a little further along, might offer better protection from them.
None-the-less, I'd love to have you try this method and compare!