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

This week, I've been getting some spinach started to go out in early March, and I wanted to share my method of starting it.  I usually start my first batch indoors so it's got a head-start at the beginning of growing season, but after that, I just put my pre-sprouted seeds right out in the garden beds.

Spinach is notoriously hard to get to germinate - if you try to start it the way that works for just about everything else.  My first few attempts were dismal, and I was about to give up.  Until - after hours of searching gardening forums and other websites - I found a few apparently obscure, but simple tricks for getting spinach to sprout reliably.  Now I do this with every batch of spinach seeds, and very easily get high germination rates within 5 days.


1: "Scarify" the seeds.

I didn't think this was a real word, but it is.  It involves various methods of breaching or compromising the seed coat to make it more permeable to moisture.  There are lots of articles and YouTube videos about this.

To do this with spinach, I take a pair of nail trimmers and nip one end of the seed.  Most of the seeds have a kind of teardrop shape.  I find the pointy end of the seed (where the first root normally comes out), and nip off a little of the seed there, just enough to expose the inside of the seed.  I try not to cut too far into the inner part of it.






You can also try just rubbing the seeds on some sandpaper to wear off some of the seed coat, which works just about as well, and some people will find this easier.


2: Soak and chill the seeds.

Once I've nipped all the seeds, I put them in a small container and completely cover them with water.  The water I use for this is a regular 16-ish oz bottle of water, to which I've added 1/4 tsp of hydrogen peroxide solution (to help prevent fungi).


Then into the refrigerator they go, for 24 hours.  Seriously.


I got the idea to try this after discovering this chart of seed germination temperatures published by Tom Clothier on his website.  I've seen the charts that show ideal germination temps for spinach being around 70-77 degrees.  But note the difference between days to germinate vs. germination rates.

According to Clothier's chart, spinach seed germinates in the fewest number of days at 77 degrees (F), but at fairly low germination rates, about 28%.  However, the highest germination rates for spinach happen at around 50 degrees, at around 91%.  But they also normally take much longer to germinate at that temperature.

This is where scarifying the seeds changes the game.  Scarified spinach seeds germinate at chilled temperatures in about the same time as you would get with warmer temperatures, but you get a germination rate you would typically get at lower temperatures.

So that's my theory.


3: Put the seeds in wet paper towels and keep them cool and dark.

End of day 1 (at the end of 24 hours in the fridge):

The seeds come out of the fridge and into some wet paper towels.  (I use lidded containers that I can re-use, but ziploc bags work fine, too.)


As you can see here, some of them - after just 24 hours - are already starting to sprout their first root.  Even so, I'm going to give them a day in the paper towels before planting them in the seed tray.



Once in the paper towels, I set them out in the garage, where the average temperature is around 60 degrees during the winter, and cover them to keep them in the dark.





End of day 2:

They're sprouting like crazy now.  I counted 27 out of the original 38 seeds that have now sprouted - that's 75% so far!  (2 of the original 38 seeds are missing somehow...   )


Any with root tails get planted in seed cells (or in the garden if it's warm enough).



End of day 3:

Now I've got a total of 30 out of the original 38 that have sprouted - 79%.  (This is a really good batch of seed I got from Lee Valley in Boulder, CO.)




End of day 4:

4 more seeds, of the remaining 6, have sprouted - 90%



End of day 5:

By day five, the seeds that were planted are beginning to emerge from the mix.  So this is shaping up into another successful start of a batch of spinach seeds.



Another benefit of this method is less waste of seeds.  The only seeds that get planted are the ones you know are sprouting.  So you don't have to fill each seed cell with 3 or 4 seeds, betting at least one of them will sprout, then end up with some where none do, or having to destroy a few seedlings to thin the cell to just one.  And once they're planted, the success rate is usually around 99%.  This is why I like to pre-sprout my seeds in general.

Thanks for sharing that was very informative for me. I might even try it out myself next time I plant spinach.

Thank you for sharing this and for the great pictures. I look forward to trying this!

Thanks CK for that great information. I'll try it with my spinach.

Seems like I learn something new everyday on this forum.

I don't start seeds indoors but may try this closer to planting time! I don't usually have good luck with spinach but this might be motivation to give it another try.

That's amazing, Kate!  I've read they we needed to scarify them but couldn't figure out how to cut that tiny seed.  Great tip!

Last year when I direct planted a few different varieties of spinach, I got an interesting surprise.  The seeds that I had harvested myself the previous year, after bolting, had an almost 100% germination rate!  The rest were the usual 50% more or less.  Not sure if this was a fluke or what, but this year I'm only planting my own and not bothering with the others.

CC

Thanks for this Kate, and so well explained. 

At least I have nail clippers and tweezers so I am on my way.

Love this! Thanks, Kate. Planning to seed spinach in the next couple of days anyway, so perfect timing!!

Thank you Kate, I've been having problems starting / growing spinach. Mainly because of reading spinach must be direct planted.. This then can be done both ways...I'm testing this week..

My usual method of planting spinach is to soak the seeds, then directly sow outside.

This innovation takes things several steps further.  Timed correctly, I don't think the seeds actually must be "started" indoors--just slightly sprouted.  Someone please correct me if I'm wrong.

I sowed mine directly outside last year and got good results. I can't remember if I pre-soaked them or not.  The seed package that I have says to sow them outside in the Spring. I may try starting some indoors this year using Kate's techniques, to get a head start on the season. I'm always willing to experiment.

donnainzone5 wrote:My usual method of planting spinach is to soak the seeds, then directly sow outside.

This innovation takes things several steps further.  Timed correctly, I don't think the seeds actually must be "started" indoors--just slightly sprouted.  Someone please correct me if I'm wrong.

No, I quite agree, they don't have to be started indoors.  Once it gets warm enough outside, you can just take the sprouted seeds straight out of the paper towel and put them right into your garden bed, and that's what I usually do.  I just sometimes start them as transplants at the beginning of the season to get a week or two head start.

One thing I will never do again is just take seeds straight out of the envelope, drop 4 of them into a hole, and wait 3 weeks for nothing to come up.  Not fun.

jimmy cee wrote:Thank you Kate, I've been having problems starting / growing spinach. Mainly because of reading spinach must be direct planted.. This then can be done both ways...I'm testing this week..

Yes, I've read that, too, and from what I have read, I believe the reason it is recommended is because of the spinach plant's root structure.  It has a tap root that shoots straight down, that is sensitive to physical stress, and it can be tough on the plant if the roots get damaged during transplant.

I have been able to raise spinach seedlings in seed starting trays and transplant them in previous seasons, and they've done fine.  I think the key is to get them transplanted before they get very far along, before the tap root reaches the bottom of whatever container it's in, or at least just be very gentle when handling the root ball.  So they don't have to be started as transplants, but in my opinion, they can be.

Yes, it can be done both ways using this method of germination.  You can just skip the transplant stage entirely, take the germinated seeds and put them straight from the paper towels into your beds, and you're still getting the benefit of planting a seed you know has already successfully sprouted.  You're getting the most out of your seeds, and it's usually a lot less time before you get to see them emerge from the Mel's Mix.

Excellent explanation, Kate.

sanderson wrote:Excellent explanation, Kate.

Yes, Kate, thank you so much for this info, I love eating spinach so much, I think Popeye is in my family's roots

CapeCoddess wrote:Last year when I direct planted a few different varieties of spinach, I got an interesting surprise.  The seeds that I had harvested myself the previous year, after bolting, had an almost 100% germination rate!  The rest were the usual 50% more or less.  Not sure if this was a fluke or what, but this year I'm only planting my own and not bothering with the others.

I don't think it was a fluke.  One thing I forgot to mention was that spinach seed has a very short shelf life.  I do not save them year after year like I can with tomato or lettuce seeds.  If they're not fresh, their germination rate drops drastically the second year.

And now that I think about it, this is another great way to get the most out of your purchased seeds.  I'm going to have to try that.

Thank you Kate. Fantastic demo, great pictures.

I was finally able to grow spinach this past year.  I also germinate the seed in damp paper towels and then transplant when I see the rootlet popping out.  Worked great.  I did not do the refrigerator part but the paper towel sure worked great.

I'l be starting some spinach indoors this weekend.

21 spinach seeds scarified, in water in fridge. Seed starting thingy filled with moistened organic starter mix, covered, found the old heating pad.....just need to find some dowels to mount my fluorescent lights....

Kate
Removed these from water in fridge this morning (Sunday)
Left them for 2 days as I forgot they were there.
Laid them out on paper and slid them in a clear bag...Some have sprouted already...
Think I will just pot them for the heck of it..see what happens..

mmy cee wrote:Kate
Removed these from water in fridge this morning (Sunday)
Left them for 2 days as I forgot they were there.
Laid them out on paper and slid them in a clear bag...Some have sprouted already...
Think I will just pot them for the heck of it..see what happens..

The one just right of the middle is definitely ready to get into some growing mix.  I think it's okay if the seeds go a little overtime in the fridge, as long as they don't start to disintegrate, or go too long underwater after sprouting.  24 hours usually does it for me, though.

Scorpio Rising wrote:21 spinach seeds scarified, in water in fridge.  Seed starting thingy filled with moistened organic starter mix, covered, found the old heating pad.....just need to find some dowels to mount my fluorescent lights....

Let's get this party started!  

Oh yeah, those little tadpoles are goin' in, baby! LOL

Then you got some sprouts, too!