Tuesday, 28 July 2015

37 shades of sweet potato

Back in the middle of June I planted out all my sweet potato starts out in the garden. I could surely have nursed some a bit longer but they were beginning to suffer indoors and, frankly, I thought that anything I planted after that day would have very little chance of producing tubers anyway. I was also struggling a bit with the logistics of it all and was eager to have them out there rather than being dependent on my undivided attention. I'll have to devise a better system for next year, though it might already help to have less varieties to sprout and keep happy...

I counted them after planting and ended up with a total of 37 varieties. In no particular order at all these were

12 commercial European/American/Asian varieties: 
T65, Nordic Purple, Nordic White, Nordic Orange, Burgundy, Bonita, Murasaki, Georgia Jet, Asian Yam 1, Asian Yam 2, Okinawa Purple, Garnet

25 (mostly) heirloom African varieties: 
Alira, Kalebe, Silek, Kanya, Uganda Orange 1, Uganda Orange 2, Kipapari, Mukekuru Tarya Bibiri, Tangara, Kitambe, Orphan, Rwabafurugi, Kitekyere, Mpame Hegia, Nyariowera, Kwezi Kume, Sula 1, Sula 2, Burundi, Bunduguza, Mushemeza, Kidodo, NASPOT 1, Bamuhachira, Magabari

A map of the 2015 batata garden
Some of these were not particularly viable though, and in some cases I just chucked a yet-unsprouted tuber in the ground, hoping that against all odds it would still do something. The amount of plants per cultivar varied a lot; of some I got 20+ plants, of others just one. This almost exclusively had to do with how fast the different tubers sprouted. For those that were very slow-going I ended up with few (or no) plants. By now some of these have quite definitely died, so I'm probably left with under 30 varieties.

Nordic Purple (left) and T65 (right)
It's been my luck of course that, exactly in the year I'm embarking on this grand sweet potato experiment, we're experiencing one of the coldest summers in decades here in Sweden. Except for a few tropical days in the beginning of July, the last few months have felt more like early autumn, with exceptionally windy, chilly and rainy weather. Predictly the sweet potatoes haven't been all too happy with this and growth is just a fraction of what it was last year at this point (though I was growing them under plastic then, so it's hard to compare). The optimist in me sees this as the perfect selection pressure and thinks that if any of these plants yields something this summer, it will reliably do so most years. My pessimist self on the other hand is quite convinced that I will end up with absolutely no sweet potatoes whatsoever. Either way I'm hoping that August will bring some direly needed sun for these:

Sula 1
Nordic Purple
If I would formulate my ambitions, they would consequently be quite modest (or at least I think so..). I would like to get some kind of tuber from at least 3 of these varieties, plus some seeds. If I would have to choose, then I suppose the latter would be the most important, since it would make possible the long, very, very long, process of breeding nordic-adapted varieties. For that to happen I will first need some more growth and some flowers though.. Indian summer, anyone?

Please, world, make it happen.

Thursday, 2 July 2015

From Amandine to Zillifera; an Andean summer update

It's high time for a brief update on this year's experiment with the Andean family of exciting tubers. Spring has been chilly here, with temperatures not much higher than 15°C for most of May and June, and the Andeans seem to have loved it. It must be that the wind and the cold reminds them of home. So far I have managed to keep all of them in reasonably good health with few if any casualties (that I recall..). I'm not sure how that rates as an indicator of gardening success but on a personal level it feels pretty satisfying.

Prematurely bereft of their identity, my blend of oca tubers has been growing steadily. Of the 30 or so that I planted I believe only four did not come up. The four plants that I had potted up in March have sized up considerably and over the past two weeks actually started flowering. Some days ago I noticed two other varieties doing the same, so I had a first go at oca pollination. Oca has a tristylous flower morphology which basically means that not all flowers are compatible (here is a more detailed decription) and you need flowers of two different types in order for succesful pollination to occur. I've yet to see if the flowers I pollinated are setting seed... The weather has actually gotten a lot warmer the past week, and oca seems to require fairly cool temperatures in order to flower, so I will probably have to wait until later this summer for more pollination opportunities. Pest-wise, oca has been fairly troublefree for me so far, the slugs don't seem too fond of it (they have decided to decimate my root parsley seedlings instead..) and not much else does either it seems. Some of the plants have some black aphid colonies but really nothing majorly worrisome. Oh, and after planting my first batch, I've received some more varieties courtesy of Rhizowen and his newfound Guild of Oca growers. These are 'brand new' varieties so it will be exciting to see what comes of them. Reassuringly also, I've managed to get these in the ground unshaken and correctly labelled. I might have a scientific career ahead of me after all.

If I can conclude one thing from my first year attempt at growing ulluco so far, it must be that it is really, really, really slow-growing. I thought I would lose these to the slugs at some point, since there seemed no way they could possibly outpace this year's onslaught of Arion vulgaris. Yet with a little help of some plastic bottles and my murderous garden scissors, they seem to have pulled through and are now... well, just standing there, really. I assume their growth will speed up at some point and who knows, they might even flower, which I will be eagerly looking out for (viable ulluco seed is very rare).


Mashua must be something of the polar opposite of ulluco. It is growing faster than anything else in my garden and has already filled the space that I had intended for it. In fact, I found three of the mashua plants invading the oca patch the other day, and one of them was happily strangling one of the oca's. Safe to say I seem to have significantly underestimated mashua's territorial requirements... It's also remarkably pest free, I have yet to see a slug, snail or aphid show any interest in it. The only creature that did fall for mashua's undisputable charms was a rabbit, which promply munched down half of the 'white' variety but left the 'zilifera' untouched. It must have been on to something there.. Both plants recovered swiftly. Mashua is related to the garden nasturtium (Tropaeolum majus) and seems to have equally interesting flowers, so I'm looking forward to seeing those. I will have to wait until September though, since mashua normally only flowers with short daylengths.

Mashua, just before it got a bit out of control

There's so much mystery surrounding mauka that this is easily one of my favourite plants at the moment. I've got two varieties growing, one red-leaved (which is either 'roja' or a red cipotato variety) and one that I grew from seed and is in all likelihood a direct descendant of the 'blanca' variety. These seem to be the only three varieties grown outside of the Andes at the moment. My objectives with it this year are first, to be finally able to taste it, which should be possible with the two plants that are in their second year now, and second, to somehow get it to produce seed. The latter will be tricky, since mauka apparently only starts flowering long into the European winter and is therefore very unlikely to produce mature seed before the frost kills it. I am planning to overwinter two plants indoors and hopefully can pursuade it to flower that way.

Mauka is fast-growing though not nearly as much as mashua. It has attracked a lot of aphids in my garden, with the result that all the growing tips have curled up. I assume this is slowing down the plant somewhat but it's still growing strongly so I see no immediate reason to start despairing. With the warmer weather of the past week, I'm also counting on increased predator activity to bring the aphid population back under control. Bring on the ladybugs!

Mauka blanca (?)
Aphid infestation in mauka growing tips

Ok, yes, so this is not exactly a tuber crop. It's all the more Andean though, so I propose that its inclusion here is fully justified. I'm trialling three kinds of quinoa this year, though I've had very poor germination with one and am yet to see if I will have any viable plants from that variety. I am also yet to be convinved that I'm actually growing quinoa and not the common garden weed lambsquarters (Chenopodium album). The two are closely related and plants look similar enough that I really can't tell them apart at the moment. I direct-sowed the quinoa in a place with plenty of lambsquarters, so the only real way to tell is to wait I suppose. I would be pretty excited to be able to grow quinoa, and going by ongoing attempts to commercialize it as a alternative agricultural crop in different European countries, this should not at all be impossible.

Quinoa (Chenopodium quinoa)

For good measure, and to do justice to the humble potato's origins, I'll include an update about this year's potatoes as well. I'm currently growing 7 varieties: Minerva, Juliette, Linzer Delikatesse, Amandine, Asterix, Arran Victory, and Mandel. I'm not exactly expecting a bumper crop since I planted them on a newly-dug piece of land that I didn't have time to prepare properly, but they should last for some months at least. I've since also read up on growing potatoes from seed ('commonly' known as TPS or True Potato Seed, as opposed to potatoes grown from seed potatoes, i.e. from tubers) and became sufficiently fascinated to put this on my (ever expanding) list of garden projects for next year. The idea is that, rather than relying on (disease-prone) tubers, you save the berries that (sometimes) form on potato plants and then grow those out to create your own locally adapted potato varieties. Incidentally, when I was thinning out the beets the other day I found one potato volunteer that must have come from one of last year's 'Sallad Blue' potatoes. Any potato that sows itself is a good potato in my opinion, so I'll consider that a humble start for next year's potato project!