Breeding Sweet Potato in Australia

[whwoz]

Set up about 14 slips in pots in float on the dam today,  will get photos shortly

[Steve1]

I have just found my swee potato flower,  on the ornamental but still a flower!!

Nice whwoz! It's slowly happening.
Wandered over to the vege patch tonight and Evangeline had flowered today and suprisingly to me so had the Okinawan (only a single flower) and the two ornamentals. Slowly, there is a bit of momentum.
Pasted some pollen around and now we wait.

[whwoz]

Way to go Steve, I had a few minutes for a quick squiz at the SP today, found half a dozen on the ornamental, but most were well hidden by growth from other plants.  I am going to have to allow a lot more room next year between plants, like about 2 meters just so that I can see flowers.  Plants in the dam look good, photo tomorrow.

[whwoz]

First up, the floating Sweet Potatoes in the Dam. Terracotta pots are there to provide weight to balance the float underneath the plastic pallet, float is 90 mm PVC pipe glued into a square.  SP slips are individually placed into 75mm pots around edge, with two slips in a 125mm square to round pot in the middle.  Not interested in tubers here, just looking to see if I can replicate Reeds effort at producing flowers.  Pallet is balance so that bottom 1 inch or so of each pot is in the water

[whwoz]

And a few photos of the main bed, showing growth, going to have to clear the paths out of weeds sometime soon and need to lift runners again to stop the rooting in.  Trellis is working to keep runners out of tomatoes as long as I lift them up roughly once a week, not seeing any flowers there at this stage.

[fon42]

looks good whwoz ....should get a good crop of tubers.

hoping to see more flower buds on the grafted sp soon. will keep you poster

cheers

[Steve1]

Well done whwoz, those sweet potatoes look great, and I reckon you will get a good crop as well. Mine are ok for such a cool season in a first year bed. That clover is my main weed (which I leave if not to close to the plants) says something about the lack of soil nitrogen.
Interestingly, today there are buds on Matt's Purple Flesh which came from Fon later than the others. I thought it might be Okinawan as the leaves are similar shape but the Okinawan I have has a long flower stalk and this is short. The leaves most resemble Kumera / Japanese. Will still be a week or two at least before it flowers.

[whwoz]

Thanks Steve1, last time I grew sweet potato in that soil was the first time I had grown them, from memory 8 kg from 2 plants, so yes, hoping for a good crop. Still not seeing a lot of flowers,  hence the floaters. 

Re clover,  when you next pull one out,  check the roots, if nodules are present you have nitrogen fixing going on, if no nodules,  no nitrogen fixing occurring.  Clover by itself does not fix nitrogen, requires Rhizobium bacteria.

Good to hear about the different varieties flowering, makes me wonder if my soil to high in N.

[reed]

I have lots of wood chips and use them in my growing.  I do it cause it's easy for me, not to control nitrogen but I guess it could have influence on flowering.
I need to figure that out some day, another controlled experiment I don't have time for right now. 

[Steve1]

Thanks Steve1, last time I grew sweet potato in that soil was the first time I had grown them, from memory 8 kg from 2 plants, so yes, hoping for a good crop. Still not seeing a lot of flowers,  hence the floaters. 

Re clover,  when you next pull one out,  check the roots, if nodules are present you have nitrogen fixing going on, if no nodules,  no nitrogen fixing occurring.  Clover by itself does not fix nitrogen, requires Rhizobium bacteria.

Good to hear about the different varieties flowering, makes me wonder if my soil to high in N.

I can only speculate that N may be part of it. All the legumes I planted last year (as part of the green manure) including the clovers were innoculaed with the right rhizobia. Some clovers are doing better than others, but good point - I'll go look for pink nodules.
The flip side of all this is that I probably wont get the SP yield you will whwoz. 

[whwoz]

Fairly quite here at work at the moment, so have been surfing to see if I can find anything relating to SP flowering and came across this again

https://www.lsuagcenter.com/portals/communications/publications/agmag/archive/2009/spring/breeding-highyielding-delicious-sweet-potatoes

from the Louisiana Agricultural Experiment Station, which is where I first got the idea that flowering can be promoted by trellising.  Obviously a lot more to it than just winding the up a frame as mine have not flowered yet despite some being elevated for over 2 months so far.  Not finding anything that relates to N levels enhancing flowering either.  Indeed comments on flowering of SP's seems to be thin on the ground and nearly as common as SP flowers in my garden atm!!

Thinking ahead to next year, I want to look at getting cuttings going in dam as early as possible, may actually be able to keep the ones in there going over winter if frosts not to bad, multiple ropes will allow me to position float where I want it and will remove some weights once roots get a reasonable length on them.  Need to try fully elevating a plant or two of each variety, even if it means trimming some of the branches.  I have several soil types available to me, need to experiment with planting in them and also look at the effect of adding tree trimmings (well composted and maybe some not so well composted) to the soil to try manipulating N levels.  Not sure what else to try.

[reed]

I've never seen that trellising promotes flowers but it certainly makes it easier to collect seeds.

[whwoz]

Reed, I suspect that like a lot of the things that you have found out about SP, its variety dependent.   Those referred to in that article were probably wild selections that by chance flowered better raised. Still a lot of unanswered questions regarding flowering in my mind

[reed]

Yea, I think you are probably right.

[Chris Morrison]

Not sure about N levels, but I reckon heat spikes set off mass flowering and seed development, just a casual observation from a newbie.
I run my gardens kinda lean, sheep shit pellets only at planting. 3 out of 4 types flowered and set seed: 2 camotes that had come from reed via Richard Watson, and one, my own native NZ 'mutation'. Okinawan did not fire. Might get a couple hundred seed, already 100 some, in the drawer. Hope that helps in some way?