2013 Oca True Seedling Selection

It was later than I intended, but several weeks ago I checked this year's seed-raised oca for early tuberisation. This is  the vital process of deselecting individuals which fail to meet the crucial criterium of earliness. It's tempting to wait and see their full potential, but a bit like shooting runt puppies, sooner is better than later. The difference here is that these puppies are nearly all runts, and the good one is a rare exception.

From my Spring sowing, I ultimately got about 25 seedlings. A couple managed to get deselected at an early stage by their own efforts, while the remainder were moved out of pots on to ground vacated by the onion crop in mid summer.

This artificially short growing period is enough to see that some individuals are clearly useless, and can be flung without any hesitation...

…while others ...

…show some promise, being of a similar size to the commercial clones that do best for me.

…So I've decided to retain tubers from four individuals, as having potential. Next year they will be grown conventionally from tubers to give them a fair chance of comparison against existing clones.

So the international search for a day-length neutral oca variety continues apace, with reports of Rhizowen at Radix, and Bill at Wetting the Beds routinely producing vast numbers of seedlings apparently with minimal effort. And Belgian Frank is no doubt quietly hatching a fresh horde for this year.

Chipboard as Soil Improver. No... Seriously!

Chipboard and MDF, with their synthetic constituents and health concerns, would not immediately spring to mind as compost material. Surely not something the organic gardener would want coming in contact with their soil — that would be my automatic reaction. But please read on!

I had a lot of scrap chipboard lying about, and got thinking about the resin glue that it contains; urea formaldehyde. That's a recognised agricultural fertiliser isn't it? So after a bit of research, I found this document about composting wood composite materials.
It's a long read, so for those that just want the highlights, it seems that chipboard and MDF, when composted with green waste, make compost that surprisingly contains less contaminants that compost made from domestic green waste alone. The urea resin is broken down by bacteria and fungi, releasing nitrogen which becomes available to combine with the high-carbon wood particles. This should counteract the usual stated disadvantage of composting wood — a temporary state of nitrogen mopping.

So I'm incorporating it into the bottom spit of my double digging on beds to be managed in future by minimum tillage, where it will provide slow release nutrients, and improve long term water-holding capacity. Deeply buried wood products may also be effective in catching soluble nutrients that would otherwise be leached by winter rain.
Not quite hugelkultur, but brings a whole new meaning to composting your kitchen scraps.

Gotta do something to improve this stuff...

If you're thinking of following my example, it's probably a bad idea to use:
-coated or foil laminated board,
-MR (flooring) grade chipboard (that's 'moisture resistant', which contains fungicides),
 -board contaminated with paint, varnish, or wood preserver.

UPDATE: There is another study here by the University of Tennessee which finds benefits from dressing soil with mdf sawdust at 8 tons/acre.

Oca/Corn/Huauzontle Polyculture — Still Seeking Low-Work Resilient Growing Systems.

In 2010 I posted here on interplanting Oca and sweetcorn. This year, I'm going a stage further by adding Huauzontle (or 'Aztec Broccoli') to that system. Huauzontle is a Chenopod crop producing greens and edible flower-shoots, historically an encouraged weed or tolerated volunteer in Central American maize fields.
Here are the three constituent crops ready to plant out on the 16th of June, Huauzontle on the left...

The Huauzontle seed came from Real Seeds, and was ridiculously fast to germinate; the seedlings were up in 48 hrs, so in future, I would direct sow with confidence. But this time they were multi-sown in cells a week or so after the corn.
The maize is Painted Mountain obtained in a seed swap parcel a few years back, (thank you Jayb). It gave 100% germination despite its age, in sowing conditions that were not really warm enough by normal standards. It's a many-coloured genetically diverse, heat and cold-resilient variety, bred to thrive in the Rocky Mountains. After last year's weather, I'm seeking resilient varieties! Two trays of commercial sweetcorn sown on the same day all rotted, thanks probably to chilly nights in the greenhouse. Not chilly by Rocky Mountain standards evidently.

The oca are a motly collection of leftovers stunted from being left in small cells too long.

Here's the scheme on planting day. That's a four foot wide bed...

 ...which has just been newly created by double digging, incorporating all available organic matter to full depth. Carrying through the resilience theme to the soil, there are even logs buried under there; anything to build up this silt soil, and give some water holding capacity.

Just four weeks after planting, quite remarkably the huauzontle was already providing greens and seed shoots for steaming, but proving too vigorous for this scheme, or at least is too thickly planted, and is shown here just before receiving a serious cutting back...

A few spare lettuce were squeezed along the edge too, and the paths mulched to limit water loss during the ensuing heatwave.

By the beginning of September the corn is ready to pick...

...and, despite occasional chopping back, the Huauzontle continued to be a bit too resilient. The Oca are definitely suffering from lack of light and water at this stage.

Here is the view of the bed on 31st October...

...The oca are expanding fast, fighting back, and flowering, with every indication of a decent harvest to be had by mid winter. The Huauzontle, disheveled by recent gale-force winds, has turned spectacularly red and carries a massive seed crop, so it seems likely that I, just like Central American peasants, will have it as a tolerated volunteer in seasons to come.
With wider spacing of the Huauzontle, this scheme would approach my ideal; no weeds had a chance, and the bed yielded well, but required almost no work input once created. And like the Forth railway bridge, it has redundancy — bits can fall off it, but it still works.