Home-made soil nutrition

Mid-Spring and two months since we’ve had rain on the Adelaide Plains…

About now I’d normally be starting to see the late winter crops drying out and I’d be struggling to start seedlings in drying soil.

But just for once I’ve got the ‘covers’ on the garden in time; a deep layer of barley straw – about 60 bales – covers all the working beds, paths and the orchard floor. Soil moisture levels are under control, needing only 10 tonne of water per week (10 000 litres) to hold steady.

But with watering and the seed table under control I’m forced to face a more insidious problem that’s been creeping up on me for some years now; the nutrition levels in these soils is starting to fall. This is particularly true along the edges of the garden bed (mesh) fences where I grow beans and cucumbers year after year.

Fortunately we’ve been saving kitchen scraps – imported nutrition – for a decade now in three Gedye bins that have been in constant rotation. Each bin takes at least a year to fill even though we throw in a bucketful of scraps each day and occasionally add green cuttings from the garden and a shovel or two of soil. Where does it all go?

So I choose the oldest bin and pull the tapered top off (the bottom is open). Compost worms everywhere! These worms - Tiger worms, Indian Blues and Red Wrigglers - are different from earthworms; they live on the surface and enjoy moist, cool, dark, oxygen-rich places with lots of food scraps to eat. This lot seem particularly fond of the cook’s lecture notes that she dumped in there; they are living between the sheets of these thick wads of old A4 paper and loving it.

This job stinks.

But I wouldn’t know – at sometime in the past I lost my sense of smell, so I’m the perfect guy for this work.

The top layer of the heap is set aside, the worms are moved to the two remaining working Gedye bins by the shovelful, the nutrition-rich worm castings at the bottom of the bin are loaded into the wheelbarrow and sieving begins.

Old cake trays make great coarse sieves for such compost, removing old bones, sticks, avocado pips and other bits of hard rubbish.

New bean trenches are hoed along the fence lines and ‘Lazy Wife’ bean seeds are dropped onto the trench floor with compost then straw mulch added on top; these large bean seeds will push through this as they germinate.

I add a brand-new drip line to totally saturate the root zone so that the beans can get out into the moist surrounding soil for extra nutrition. The cook helps out by planting the cucumber seedlings, adding compost and back-mulching as well.

And that’s that.

Except that – a day later – there’s still a funny smell lingering around wherever I am. Even I can occasionally detect it.

Luckily the cook is away at a seminar in the Barossa Valley or I’d be sleeping down the back-shed tonight…

Winter mulch and caterpillar wars

The winter rains have come at last and a whole new bunch of water management problems confront the gardener - how to get about safely on boggy paths.

Fortunately the solution is both simple and benefits the garden in the long-term; we lay down our summer mulch on winter paths six months before we need it to retain soil moisture in the rising temperatures of Spring. The winter rains will soften this barley straw and begin the process of breaking it down so that in a year’s time it will have been incorporated into an organic soil richer for the extra carbon.

The chicken flock will walk on this drier surface throughout winter and scratch it about in their search for the insect life that will build up under there in the layer where straw meets soil. The softer straw that results is largely pest and seed free and is much easier to lay carefully around new Spring seedlings.

On a different front, the butterflies of autumn have laid their eggs on green plants and have hatched caterpillars that are hacking apart crops of comfrey, silverbeet and German cabbage.

 

These Cabbage White (Pieris rapae) green caterpillars on the green leaves of the cabbages are almost impossible for a human to spot and squash so its tempting to turn the chooks in to clean them up. Sadly, chickens love eating cabbage leaves even more than caterpillars do, so I need to search the leaves for them myself, tossing them over the fence to the chooks waiting eagerly on the other side.

‘Black woolly bear’ caterpillars (the larvae of a native ‘black and white tiger moth’) are even more damaging because they don’t seem to have any natural predators – even the chooks won’t touch them.  I also pluck these off the comfrey and silverbeet leaves and toss them out onto the path with the mulch. Let them walk and work to get to feed on my vegetables, I say.

Weird things in a winter garden

Winter is upon us in southern Australia, yet there is no let-up in the effort required in the garden. If anything, pressures are building back up again as I try to make space for onions, beetroot and spring flowers (still in the seed trays) while trying to keep the rain-fed chaos of self-seeded pathways under control.

I’ve given up even pretending to be on top of things. But I’ve found a few odd moments to catalogue some of the winter wonders springing up all over the place…

 

 

Adding some winter colour to the verdant green of the overflowing beds, my chilli collection is starting to ripen and will be used to refresh my seed collection as they mature.

 

 

And what are the names of all these chillies? Sadly, I forget. Some are spherical, some are small pointy multi-coloured ones with an upright characteristic, others are deep purple and some are the regular long skinny droopy ones alongside a different variety having a bell-lantern shape.

There is beauty in vegetable gardens if one looks closely.

Among the rogue salad collection are the Italian bitter lettuces that I know I grew on purpose, didn’t eat much of, but then let the plants go naturally to seed because of their pretty blue flowers, so unlike the thistle-type flowers of all other lettuces.

Now they are all over the dirt pathways, and we find ourselves making long detours to allow them their own space rather than treading them underfoot.

 

 

In the orchard, one of the peach trees is still suffering from the after-effects of the massive 2013 peach harvest and is now under attack from bracket fungi where limbs had to be removed and the bark on the main trunk started to split.

 

 

 

 

The tomato crops and their bamboo frames have had to be pulled out to make way for the onions. All the old mulch and new weeds have had to be hoed out and thrown onto the pathways for natural composting. This soil and weed mix will soon be covered with new barley straw to over-winter and break down under the scratching of the hens and the softening effects of the winter rains. This ‘path composting’ process will deliver soft mulch and fresh organic matter to garden soil as it accumulates year after year.

All the necessary hoeing turns up plenty of earthworms; the chooks follow my work closely and enjoy the fresh protein. Every meter or so I turn up some soil-borne grubs that I believe (without any evidence) to be ‘mole cricket larvae’; these are a special delicacy to the hens. I pick them out of the trenches and throw them in front of the flock where they are snatched up.

Ah well, that’s my fun for the day. Now its back to planting out all those onions…

Harvesting ‘bamboo’ for use in the garden

‘Giant Cane’ – Arundo Donax – is an ornamental plant that lives life on the edge of being declared a noxious weed because of its invasive habits along disturbed riparian (riverside) environments as far afield as Europe and California. While its origins are obscure, some claim that it comes from India or perhaps from Mediterranean regions.

In South Australia ‘giant cane’ is just called ‘bamboo’, because that’s what it looks like. It has been cultivated here for many decades by the old Italian market gardeners who grew it for use as tomato stakes and bean poles, among other things. Many of the old homes that had big gardens out the back – including this one – had this cane growing in some obscure corner of the yard from where it was cut at intervals.

In our garden it has grown for the past twenty years behind the old chicken shed; here it has formed an impenetrable thicket growing out of a woody invasive root system that seems impossible to dig out or kill off. The only way to get at the canes is to cut them at the base with the electric chainsaw and drag the long strong hollow poles out of there to be processed somewhere where there is more room.

These poles are 2-3 cms in diameter, light, smooth, strong and up to 3m tall. At the end of each summer they produce feathery flower heads high up, though growth always seems to be via the root system.

The leafy tops  are cut off with heavy-duty loppers and any remaining stray side leaves are pulled off by hand. This pile of leaves and twiggy or broken malformed canes is put through the shredder to be recycled as mulch. The mulch goes back under the fruit trees, as it’s splintery stuff and not much fun to walk on.

Arundo donax canes don’t last as long as real bamboo staves but will be good for a year or two before they become too brittle and liable to split when handled. Canes are stored by standing them on end in a corner out of direct sunlight. Leaving them on the ground over winter hastens rotting.

 

 

 

 

The poles themselves are cable-tied to steel droppers to form a smooth ‘tomato wall’ along either side of my young tomato plants. For many years I built tepee trellis’ or tied tomato plants onto individual jarrah stakes, nipping and pruning the tomato vines in the hope of greater yields. I’ve become convinced however that simply touching tomato plants starts the diseases off that they seem so prone to. These smooth cane fences minimize friction while preventing the vines sprawling into the mulch, while saving much labour in tying and training.

The last week of Spring

The months of work leading up to Spring changeover in the garden are just about over; there remains but one week of Spring to oust winter crops and transplant Spring seedlings from trays into beds to finish establishing crops that will mature over our southern summer months to be harvested from February through to May next year.

Bed 3 of 13 has been cleared of the last of the winter broccoli and kale and broad beans, but I’ve lost all my soil moisture by failing to clear out these seeding giants soon enough. So last week’s watering with the rainbow sprinkler is followed this week by a thick covering of new barley straw mulch, pinned in place by new drip lines to wet up the soil lines along which tomatoes, basil, coriander, red Dutch cabbage and eggplants will be planted out.

It’s nerve wracking to have the taps running for many hours on end filling the irrigation tanks that drive these drip lines. But that’s what I need to do to get these seedlings established.

Maybe next year I’ll get it right, and so save on all that valuable water being put out on the eve of summer?

Ah well, the gardening expenses of water, mulch and irrigation pipe are long-term investments in my learning how to drive this garden efficiently once global warming starts messing with the climate and the rainfall. I’ll continue to have fresh and nutritious food up at the house after each day’s work.

All the usual Spring chaos

The October long weekend (Labour Day Holiday) arrives, and the garden pressures are already rising along with the warming Spring temperatures. At the same time, my expectations of further soaking rains of 12mm or more are diminishing, so it’s time to get the covers on the garden so that I can save what winter moisture I have accumulated in the soil profile to offset future water bills.

All goes smoothly enough while I’m using simple tools such as the three-pronged hay fork. But the wheelbarrow has blown a tire after thirty years of loyal service, so I have to fix that before I can begin. [All I did to trigger this catastrophe was to stack 80 kg of premix concrete into the barrow for the new chicken shed]

When all my friable mulch – overwintered on the garden paths and broken down by the scratching of the chicken flock – has been placed around lettuce, onion and garlic crops, its time to shred my supplemental stockpiles of cuttings and trimmings from the orchard.

For the first time in twenty years, this wonderfully reliable machine refuses to start. Out come the tools, and I wire-brush the sparkplug, empty the fuel tank and clean the air filter. To no avail – I will have to send it off to the repair place.

The three day holiday is over, the mulching is done, but the shredding and chicken shed are in limbo. Now there’s nothing for it but to revert to the hand-tools; I clean out all the winter thistles and nettles around the old chicken shed so that I have something to show for the passage of time.

Spring mulching

At the end of winter, below-average rainfall and unseasonably hot weather have combined to push the panic-button on capturing the last rainfall events in the soil before the eight months of dry weather are upon us. The main rainwater tanks are full, so now I need to lock down twice that volume of water in the ‘big brown tank’ that is the garden itself; this is done by mulching the surface under a thick layer of friable straw.

So all the fun of planting out Spring seeds and seedlings goes on hold, and the winter stores of barley straw – laid down in autumn on the paths and since worked over thoroughly by the chickens and watered by winter rainfall – is moved into the orchard under the burgeoning green of the table grapes, peaches and raspberries. Other beds will be mulched in similar fashion over the coming weeks.

Simply covering the soil in this way is worth the original cost of the straw three times over; mulch reduces the water bill and adds to the nutritional stores of carbon in our soils.

Somewhere in the next decade, I’ll get out of the work force and will be looking to these same soils to feed both cook and gardener for a further twenty years. Such wonderfully warm and rich organic soils can’t be trucked in; they need to be created in-situ over the span of at least a decade.

Mulch has additional benefits. It encourages earth worms to work up to the moist cool surface of the soil just below the mulch, and to mix this organic matter deeper down. The wormholes left behind (called ‘macropores’) allow the soil to breathe and roots to find their way deeper down, giving our fruit and vegetable crops added resilience when the hot weather comes.

Garlic Sunday

It’s the last weekend in autumn down-under in southern Australia and therefore ‘Garlic Sunday’ on the Adelaide Plains.

Faced with the annual pilgrimage to Germany, as of next weekend, it’s also my last chance to get the early garlic planted out and the winter mulch onto the garden paths. Pretty much everything else is in order after eight months of effort since our return from Germany at the start of the Australian Spring in September last year. Summer crops have come and gone, autumn and winter crops are planted, all thirteen garden beds are full, but my stock of seed garlic is dawdling along and refusing to be ready…

So there’s nothing for it but to go along with Mother Nature at her own pace; I can clearly only plant out those garlic varieties that have sprouted in readiness for the new season. The two varieties that are half ready – ‘Monaro Purple’ and ‘Shantung’ – get picked over and the garlic cloves broken out ready for dropping (sprout up) in the trenches.

The other varieties  - ‘Printanor’, ‘Ail de Pays Gers’ and ‘Italian White’ – are still locked down hard inside their skins, and so will be placed in the shed on my work bench in the sun for the five weeks of my absence to shift them along a bit. By then the cold weather will have set in, and I’ll be able to occupy myself planting out the last 8 kg of seed garlic during the sunny middle hours of our winter days. 

How to Plant Carrots

Five weeks into autumn, and with the weather staying mild and pleasant, its time to harvest the potatoes and plant the carrots while the soil remains warm and un-water-logged by too frequent rain. I’ll be planting four varieties from commercial seed packets this season, as I need to re-establish some diversity in my carrot seed collection, which has concentrated on ‘Nantes’ but does not yet include ‘Topweight’, ‘Chantenay’ and ‘Purple’. (Just how I keep these four from cross-pollinating when the carrot blooms form in two year’s time is a story for another day!)

Purple carrots? According to the Seed Savers’ Handbook the origin of carrots is: ‘Native to many regions, including parts of Europe, northern Africa, Afghanistan and Central Asia. Carrots were first used as medicine. They come in many colours. Purple carrots arrived in Western Europe from the Middle East in the Middle Ages. After considerable selection, these evolved into yellow ones. Not until much later did a Dutch gardener obtain a mutation which had the orange pigment familiar today. By the Middle Ages the Japanese had developed unusually long carrots adapted to their cuisine.’

Carrots need a deep friable loamy soil free of coarse material and without too much nitrogen fertiliser, as this causes ‘forking’ of the carrot root. The best way to create such a soil is to plant potatoes as the lead-in crop; both the mounding of potatoes and the deep digging needed to harvest the potato tubers creates a rich and friable loam. I’ve known for some time now that this small crop of ‘Dutch Cream’ potatoes was going to be disappointing, and I haven’t been disappointed – they're rubbish! (Digging around the potato plant roots when the plants were still green and thriving showed no sign of the usual large tubers present; this sometimes happens with the wrong variety in the wrong place). However, the soil in this small spot – perfect for planting high density carrots – is now just about ideal – deep and crumbly with plenty of organic matter to feed the roots and later, us.

Once the deep digging has been completed with the ‘potato hoe’ – a far better implement than a garden fork – the soil surface is raked level and the last of the mulch and bits and pieces removed. Carrot seeds are fairly small and slow growing, so they need to be kept moist despite being planted in the shallow surface layer just a few millimetres down. I simply scatter the carrot seed across the surface, then use a large 5 mm sieve to cover these gently with more fine crumbly soil particles before tamping down by smacking the soil surface gently with my open hand to ‘bed in’ the seed.

The trick to raising carrot seeds is to find a way to water this very narrow surface layer while preventing it from drying out during sunny weather. In the old days, we used to do this by covering the seeded area with second-hand underfelt, often to be found on footpaths during hard rubbish collection week. Sadly, this wonderful material is becoming scarce – modern carpets use a foam rubber underlay to give it that comforting springy feel. So these days I use folded shade cloth lain on the surface; one can water through this with the watering can while it keeps the soil surface shaded for the first four or five days needed for carrot seed germination. The corners of this shade cloth are pinned down by bricks, or by wooden stakes laid across them. I check every few days to see if the carrot seeds are up; at this point they are rather yellow and in need of sunlight to keep going, so the cover is permanently removed. When the carrots are some weeks old and standing approximately  50 mm (2”) high, thinning can begin to a spacing of just slightly more than the diameter of a fully grown carrot. This ‘scattered seed’ method gives me more carrots per square metre than the old business of trying to raise carrots in rows. As for the old mulch that covered the potato crop during the heat of summer, its barrowed down to the chook yard and dumped for the chickens to scratch through it, turning all those slater beetles and earwigs into tomorrow's eggs.

Autumn plantings in an Adelaide Kitchen Garden

Harvest and autumn plantings are combining to keep cook and gardener busy at a time when many other gardens in the district are beginning to wind down following ‘summer only’ crops such as tomatoes, zucchinis, beans and cucumbers.

That this new round of plantings is possible owes much to the mild Mediterranean climate that we enjoy here on the Adelaide Plains; dry hot summers followed by cool wet winters. The absence of serious frosts owes much to the nearby ocean and allows us to grow all sorts of useful foodstuffs through the coming cooler months.

Indeed, some of these crops need short days and cold nights to begin to bear fruit or edible flowers or bulbs; asparagus, garlic, red, cream, white and brown onions, broccoli, broad beans, kohl rabi, cabbage, cauliflower, Brussel sprouts, potatoes, leek, Cos lettuce, parsnips, peas, Daikon radish, corn salad, shallots, kale, rocket, Mesclun mix, Mizuna, carrots, Chinese cabbages and stir-fry vegetables such as Pak Choy and Wong Bok, celeriac, silverbeet and spinach, turnips and swedes, chives, dill, coriander, fennel, marjoram, lemon balm, comfrey, nettles, parsley, peppermint, sage, rue, rosemary, sorrel, wormwood, nasturtiums and sunflowers are some of the herbs and vegetables, while the almond and citrus trees (grapefruit, oranges, mandarins and lemons) will also crop in late winter and early spring. If space permits, green manure crops such as barley or wheat will be grown for chook food and next year’s mulch. Raspberries are coming into their second (autumn) crop.

So seeds saved last year were planted out in February, protected from ultraviolet damage by shade cloth and are now entering garden beds that the chicken flock has worked over for weeks to clear of insect pests that grew in the summer mulch. Water has been going on in these autumn/winter beds, even when they lay fallow under mulch during the hottest days of summer; this is an important part of the preparation for planting, as it keeps the soil biota (worms, fungi, bacteria, insects) alive and healthy for the arrival of the new seedlings.

So now a whole new round of plantings begins while the soil is still warm, while there is that wonderful soft yellow autumn light to drive photosynthesis and growth until well into May, and while we wait for the refreshing autumn rains.

Growing crops year round is an essential part of getting the garden to provide fresh food to the kitchen and for the maintenance of harmony between cook and gardener – a relationship often strained by early autumn as we try to cope with the sheer abundance of crops that must be handled.

And what are we looking forward to most at the moment? Fresh rain-fed salads and green beans, the first capsicums and a cold crisp evening worthy of new pumpkin soup!