When are you planting your oca and how deep?

[northepaul]

Where did you store them?

Last year I had mine in my cold bedroom and put them on a cold windowsill for a month to see if they would sprout, they didn't.
Some this year I washed and some not. The washed ones seem to be a bit softer, but then I did dig them up first.

I would guess in a cold place, but not frosty, and out of the light would be the best place, probably in sand in the shed.

I seem to have a shrinkage/shrivelling problem with some of mine, with the ones about 1" round being the best to survive.

I kept them in a cool dark cupboard in the envelope they came in.

These were just black mush...so definately rotted.

[Ian Pearson]

Just joined today - my first post.
Oca is one of my favorite crops, and I've grown it for a few years now. I have a blog devoted to Oca:
Growing Oca
where I'm recording various trials.
Womble, there's no rush to get them in the ground. If they are starting to sprout then the can be put in small pots to keep them going. Alternatively, they can be planted out if there is no risk of frost. I wouldn't put them too deep though, as the soil will still be cold down there, and the tubers will sulk until they warm up.
Snohare, the rotting may have been caused by some of the tubers catching some frost before you harvested. They tend to rot and smell bad. Storing in dryish spent compost works well. There is a dormancy period of about 60 days. I'm not sure yet if this dormancy period has a chilling requirement as well.
I have good results with Red, but suspect different varieties may do best in different conditions/soil etc.

Anyway, there is still lots to discover about this crop, and I know that some people are working on breeding non-daylength-sensitive varieties, so I'm sure it has a great future. I recommend growing it as a bi-crop. It does well with cordon tomatoes, producing up to 1.5kg per plant.
I have red oca available if anyone is desperate. Be quick, it's sprouting!

[womble]

Hi Ian and welcome to the vine.

Yours was one of the web sites I looked at, off to look at it in more detail.
I'm starting to have a bit of a problem with some of my tubers drying up severely.
I think I'm going to put them into small pots and stick them in the back porch.

I think you're right about the tubers rotting if they get frosted, I'm certain this has happened to some of mine.

[Magiccat1978]

Hi Ian and welcome. I have no experience of growing Oca but have had a quick read of your site and its very interesting, I have just been reading about interplanting with tomatoes and wouldn't mind having a go at this this year as I wouldnt loose much if it doesnt work for me.

[sarraceniac]

Hi Ian and welcome to the mad house. You are right about frosting causing softening and rotting after a few weeks. The first year I grew Oca I wanted to save some seed tubers but also heard that the frost helps them swell. I had to buy more tubers the following year because none of mine, harvested after a good frost to knock back the top growth, survived the 4 months to planting. I now take my seed tubers early, before a hard frost. They are small but that doesn't seem to affect their seeding ability. I still take my eaters after the hard frost. This works for me and if anyone has problems with seed Oca rotting, try this.

[Ian Pearson]

Thanks for the welcome folks.

Sarraceniac, "frost helps them swell". Mmm not exactly. Tubers continue to increase in size after the plants have died down (e.g. after frosting). It is not the actual frost that is critical.
If you are in an area prone to frost, it is probably worth earthing up. I have no evidence that this increases yield, but it would definitely protect the tubers from frost damage.

If the tubers are frosted, you will know about it. The smell is very unpleasant within a couple of days of the tubers thawing out! Unpleasant photo of frosted tubers here:
Growing Oca: Oca versus Frost

[womble]

Yes I've had that with the tubers going white and rotting, I guessed it was frost.
Back last year I did a thread entitled" Shall I earth up my oca" or something like that, I did, but I now see I should have done more.

I've had problems with tubers drying out, even though they've only been up since Jan, I'll stick a photo up tomorrow if I remember.

I have to say, your oca looks amazing Ian.

[sarraceniac]

Thanks for the welcome folks.

Sarraceniac, "frost helps them swell". Mmm not exactly. Tubers continue to increase in size after the plants have died down (e.g. after frosting). It is not the actual frost that is critical.
If you are in an area prone to frost, it is probably worth earthing up. I have no evidence that this increases yield, but it would definitely protect the tubers from frost damage.

If the tubers are frosted, you will know about it. The smell is very unpleasant within a couple of days of the tubers thawing out! Unpleasant photo of frosted tubers here:
Growing Oca: Oca versus Frost

Can you clarify this Ian please? I was told that the frost knocked back the top growth and the sap from the dying top growth went back into the tubers making them swell. Therefore, indirectly, the frost is the prime cause of the tubers swelling. What actually does happen?

I do know that this (just gone) winter was weird. In this area, which is not prone to frost in a normal winter, maybe only 3 or 4 days all winter in my garden, we didn't get a frost right up to Christmas. We were going to have some Oca over the festive season but the tubers remained very small. I took out enough seed for this year. Then hard frost after hard frost. By the time I got to the last tubers, they were, as per your photo, a near mush.

[Ian Pearson]

Sarraceniac, I just meant that the foliage would die down gradually even if there was no frost. As it dies down for whatever reason, as you said quite correctly, the tubers seem to take up sap from the stems, and continue to swell. (to be fair, I have no experience of growing in frost-free areas, but this is what I have heard).

Oca has evolved at high altitude, so has adapted to frosts. Hence this mechanism. However, this winter we had continuous frost, day and night, during the crucial period. My guess is that frozen stems will not transport sap.

Still learning!

[womble]

Sarraceniac, I just meant that the foliage would die down gradually even if there was no frost. As it dies down for whatever reason, as you said quite correctly, the tubers seem to take up sap from the stems, and continue to swell. (to be fair, I have no experience of growing in frost-free areas, but this is what I have heard).

Oca has evolved at high altitude, so has adapted to frosts. Hence this mechanism. However, this winter we had continuous frost, day and night, during the crucial period. My guess is that frozen stems will not transport sap.

Still learning!

I think you are right again with the frozen stems not being able to transport the sap.
It was a strange year and I think the weather has to be right to get a good crop of Oca.

I think waiting for a decent frost to mostly kill off the foliage, then covering with a decent depth of soil, is the way to go for me.
Just itching to get digging them up at the end of the year now

I wish we could have 4 growing seasons a year!

[snohare]

It was actually a blue/white mould that was the problem with most of mine. A couple of them were frosted - easily seen from colour and texture, and of course it is immediate when you take them indoors. It was a week or two later that I started to find first the occasional one, then as time went on increasing numbers, with mould growing in the nooks and crannies. I had washed virtually all of them - I think that is part of the problem, the few that I did not wash but left dirt covered, like carrots, were much less prone to musts.
It's worth noting that some tuberous plants will continue to absorb nutrition from the roots even, and sometimes especially, when the foliage is gone; I'd guess that the better the root system for the ocas, the bigger the ocas bulk up to, as all the nutrients normally used to produce foliage would go into the tubers. We think of plants as being things with green leaves that die when they are gone - Mother Nature has an entirely different take on it !
What I thought of doing with mine in future is making a sloping bank with florists buckets full of growing medium side by side buried in the soil. Each bucket would have a seed tuber. As the plants grew the embankment would become decorative, and once the foliage was over I could lay frost protection on top of the soil, and remove bucketfuls of tubers (hopefully!) as and when needed. If the frost got too cold, then I could take them into storage elsewhere.
The funny thing is, I have a double bifid kidney (malformed and not so efficient) and I suffer from the occasional kidney stone, so if I get big yields I won't be able to eat them anyway, all I'll be able to do is give them away.

[Ian Pearson]

Hi Snohare
It's amazing that cleaning something makes it more prone to attack from fungus, but I'm quite happy with the idea that we remove 'good' fungi when we clean veg, leaving a vacancy for 'bad' fungi. I also avoid using sterilised seed compost for the same reason. I get less damping off when using 'dirty' compost.
I had been thinking that the tubers would pull goodness from the roots (as they died) but of course, they may not die immediately just because the foliage has died. In fact, the roots stay looking alive up to a month after the foliage has died. They could be actively feeding the tubers rather than just getting the life sucked out of them.
The bucket embankment system sounds interesting. We need a photo when you get it sorted out!
If you get a crop in Crathie, it shows it can be grown anywhere in the UK. I have personal experience of how cold it is thereabouts.
The acid content that you purport to is hugely reduced by storage, and 'sunning' for a week or so in a greenhouse or window ledge, so maybe you will be able to enjoy them. Different varieties appear to have varying amounts of oxalic acid.