Ipomoea batatas - breeding of Sweet Potato - Camote - New Zealand

[reed]

I've read lots of places that nicking the seed works. I had I guess 40% maybe a little more germinate in the direct planted spot this year. Several just got left where they were cause I didn't have pots or room for them and were too overcrowded and not watered to make much roots but several made a few seeds. I imagine more of them will sprout next year.

I think I'll just stick with selecting for those that sprout a little easier cause I think turning them into a direct planted annual is even better than having to do it inside or in cold frames. Maybe it will just always be that if I want 25 plants I'll need to plant 50 seeds.

I would just write off the unsprouted ones. More will probably sprout even if you just discard them on the ground but if they don't do it while there is still at least 100 days left to the season they won't have time to account to much. There are some volunteers in my garden right now that sprouted in the last month. 

[Richard Watson]

Well Ive got heaps of seed sitting in the pots doing nothing, i might just stick the pots outside and see what happens over summer 

[reed]

I bet a nickel if you do that more will sprout. I have set unsprouted ones aside and basically forgot them a lot of times. I've noticed more than once that after a period of completely drying out more will sprout the next time it rains.

[Richard Watson]

might try that, dry it out then stick em outside in the rain.

[reed]

Only problem is they just keep sprouting a few at a time. Here if they aren't up by late July they don't have to time to make much roots but even those sprouting into August still bloom some. If they sprout in September or later just forget it.

[whwoz]

Reading all this about tough seed coats is making me wonder how they would cope with the old hot water poured over them treatment we use here in Oz for our native pea and wattle seed.  might give it a go on some Kang Kong, I.aquatica, which has the same erratic germination.

[Chris Morrison]

Hows about complete immersion? We know SP love water. I am thinking to dig some unsprouted seed out, and place in jar, in clean water , in my hot water cupboard. Check each day and transplant any sprouters out to soil pots. Change water regularly. Any thoughts?

[Richard Watson]

Worth a go

[Chris Morrison]

Righto. I picked thru 17 jiffy pots, and recovered 9 rock hard native EFR seed, that had been planted 2 months ago. I found one squishy rotten seed, and the rest must either have rotted out, or I simply could not find them amongst the potting mix. The 9 goodies have gone in the HWC on a well wetting napkin. See what happens. I really want these to strike, as had so few EFR for a start.

[Richard Watson]

I have had a dig around but man they are hard to find, I'm using compost so that makes it harder to see em.

[Chris Morrison]

All that time and DNA wasted ... when we thought the hard-bit was over.
Scarifying
Tip
""Morning glories, wild indigo, bluebonnet, hollyhock, lupine, sweet pea and legumes are some of the many kinds of seeds that you must scarify prior to planting.

https://www.gardenguides.com/86284-scarify-seeds.html   

[reed]

That method of soaking like your doing sounds to me like it might work. Are they showing any signs that they might sprout?

[Chris Morrison]

Not yet. Added 25% ACV for 24 hours, then put back in soil. Should know in a week hopefully.

[reed]

I never tried it but soaking in warm or even hot water is the only thing I ever considered to increase germination.

I have on occasion when looking for ones that hadn't sprouted found one that was just getting ready to. They looked like tiny little brains. Swelled up to about twice the size and covered with what looked like the beginnings of little cracks in the seed coat.

I've wondered if that might be a sign to look for if using the soaking method, when they start to swell up, time to get them in the dirt.

The other thing I think might work is heat. Steady heat, 26 - 30 degrees might do the trick. I haven't done that either though, cause I want to select for a line that doesn't need it.

What is ACV?

[Chris Morrison]

ACV = Apple Cider Vinegar. Just following advice from the link I posted last week re Scarifying. Fingers crossed, really need my native seed (at least) to fire, if at all poss. I would theorize that the best DNA is contained within the hardest seed coats, just as many edible plants, grown 'hard' or even stressed, produce the best eating and keeping qualities. A longshot theory but the other way to look at this, is , maximizing  germ via scarifying may be a very simple hack vs all the hours foraging for seed over 3 months? Thanks for the info on seed-swell, that is helpful. Now I wish I left them on the wet napkin to imbibe, haha, more trials to come. Should have several thousand seed from the coming season, have to do better than 5% germ.