Soil & Health
Association of New Zealand Inc (est 1941) Healthy
Soil - Healthy Food - Healthy People |
New Zealand's leading source of information on Organics & Sustainable Living
Levin Branch September 200721-09-2007Organic Growing News Newsletter 243 GARY WILLIAMS ON NANOTECHNOLOGY Sunday 30 September at 1.30pm Gary will talk about nanotechnology at Thompson House, 4 Kent St, Levin. This cutting-edge technology manipulates matter at the scale of individual atoms and molecules. Much speculation exists as to what may result from these lines of research, with potentially huge implications for many aspects of our lives. See page 6 inside for further details. All welcome. $2 gate charge. Sales table and afternoon tea provided. If you are coming from Wellington for any of our meetings, you might like to call Shirley Hampton on (04) 934 3621 to arrange a car pool. Future meetings:
TONY ROBINSON ON WEEDS More than 60 people attended our August meeting in Thompson House to hear Tony Robinson’s talk on weeds and what they can tell us about the soil. “Weed” is an old Anglo-Saxon word meaning “little herb”, with the word “herb” having a sense of “healing”. In effect, weeds heal and protect the soil. In 1855, Just von Liebig in his work Agricultural Chemistry proclaimed that only nitrogen, phosphorous and potassium (N, P, K) were essential for plant growth. He also claimed that there was no difference between fertiliser from a “dead” source and that from a “living” source. The burgeoning industrialists of the time seized on this, and the inorganic fertiliser industry was born. This proved to be highly successful, since the application of NPK appeared to work very well. After further study von Liebig changed his mind, but it was too late. By about 1920, it had become apparent that crops were not growing as they should. A number of people began to question and investigate this, including William Albrecht, Rudolph Steiner, Eve Balfour, Albert Howard and various American medical doctors. The answers that they, and von Liebig, came up with are this: Over time, artificial fertilisers and pesticides destroy the structure and biology of the soil. Degraded soil encourages the proliferation of specific weeds, depending on nutrient availability and the soil structure and type. The function of these weeds is to replace or make available missing nutrients in the soil. Healthy plants need a range of available nutrients and a healthy living soil biology. Almost every single weed indicates a lack of calcium (Ca) availability. Calcium is the transporter of all the other minerals, necessary to make them available to the plant. An element might be present in the soil, but in an unavailable form because of a calcium deficiency. The easiest way to add calcium is through flour or fine lime, up to 100 grams/m2/year. Flour or fine lime is available in 25kg bags from Farmlands, Otaki and Levin. The home gardener can also make a brew using hydrated or slaked lime and a little molasses. Carefully add one part lime to ten parts water – it will react – and leave overnight. Pour the water off, add a teaspoon of molasses per 5 litres, and leave a day or two. A very fine lime, Bio-Calcium, is now available in NZ. It is treated with formic acid, an extract of humic acid, which chelates the calcium and makes it available. Gypsum, or calcium sulphate, can be used at a maximum of 25g/m2, twice a year. Use around acid-loving plants such as rhododendron and azalea to add calcium without affecting soil pH. Good against thrips, which indicate a lack of calcium. Dolomite, containing magnesium, should be used sparingly. It’s great for making mud bricks. Add 25g/m2 maximum, plus plenty of compost. Epsom salts are a good way to add magnesium. With the lime you also need to add soil biology, through compost for example. Soil biology is the key to unlocking phosphorous. Healthy pasture requires only 1.3% phosphorous, so long as it is available. With good soil biology, and adequate calcium and other minerals, you will still have weeds. But they will only grow so high, and the crop will grow through and eventually smother them. The biology in your compost will be more or less fungal or bacterial, depending on how it was made. Different plants respond to different biologies. Simple pioneer weeds on cleared land require largely bacterial activity. At the other extreme, forest plants rely on mainly fungal activity – the forest mushrooms and toadstools. Vegetable gardens need a more bacterial balance, which can be achieved by adding more green material to the compost. Perennials and trees prefer a fungus-dominated compost – add more woody material and tree litter. Overall, your home-made compost should have a good mix of fungi and bacteria. It is a good idea to put all garden inputs (wood ash, rock dust, manures, etc) through your compost, to activate them and eliminate any harshness. Wood ash contains a lot of potassium (not liked by potatoes) and carbon, but becomes volatile in contact with air. Try brewing 2kg of good compost in a 10 litre bucket of water fitted with an aquarium bubbler for a day or two. Spray around garden after spreading calcium to get sluggish soil biology going. Another way to add biology and kick-start your garden’s nutrient cycling is protozoa water. Soak hay in a bucket for 2-3 days, stir, dilute 1:10, spray. The main groups of weeds are broadleaf, grasses, succulents, perennials, weeds of neglect and annuals. Note that, in assessing soils, you should always look at the whole basket of weeds and not any one in isolation. Broadleaf weeds, such as dandelion, indicate an imbalance between potassium (K) and phosphorous (P). P should be greater than K, 2:1 in home gardens or 4:1 in pasture. Often P is present but not available. Broadleaves’ taproots suck calcium up from the soil, releasing it when the weed dies. The calcium is then available to release locked-up minerals. Grassy weeds indicate tight soils. This can happen by using too much dolomite, leading to an excess of magnesium (Mg) in relation to calcium. A teaspoonful of dolomite per square metre is plenty. Rhizomes like couch grass open up the soil. Succulents indicate a lack of carbon (C). Carbon forms humus, which feeds the bacteria and fungi, which feed the soil. Carbon is lost through tilling, especially rotary hoeing. Succulents often thrive in dry sandy soil. They add carbon back to the soil around their root zone when they die. Perennials loosen up and aerate the soil. They also add calcium and phosphorous. Weeds of neglect, such as wild carrot, fennel and wild turnip, feed the soil biology and add calcium Annual weeds like chickweed and fathen indicate good soils. They help to release available nutrients and protect the soil. Insects indicate a lack of available calcium and phosphorous. Insects en masse show too much nitrogen through the over-application of manure or fertiliser. A brix level over 12 or 15 is good. Insects get drunk on the high sugar level and don’t like it. Fungal diseases like black spot indicate low phosphorous, calcium, copper and iron. For Tony’s ideal home garden treatment add, in order: * 20-30g/m2 soft rock phosphate (calcium phosphate, eg: Pacific Biofert’s “BioPhos”, available from HortMax Wairarapa) * 60g/m2 fine or flour lime (calcium carbonate) * light dressing of chicken or animal manure * 10g/m2 sulphate of ammonia * 2.5kg/m2 compost over the top of all Work in lightly, leave two weeks. Work in again, leave one week. Plant. Specific weeds and pests covered in the question and answer session were:
NANOTECHNOLOGY – A PRIMER Nanotechnology works at the level of individual atoms and molecules, with sizes measured in nanometres (billionths of a meter). Much of the fascination with nanotechnology stems from the unique quantum and surface phenomena that matter exhibits at the nanoscale. Copper becomes transparent, gold turns to liquid at room temperatures, insulators such as silicon become conductors. The ratio of surface area to volume becomes extremely high, with potent catalytic effects. “Molecular nanotechnology”, “molecular manufacturing” and “engineered nanosystems” refer to the concept of a machine that can produce a desired structure or device atom-by-atom. OCTOBER IN THE ORGANIC GARDEN (extracts from our “Regional Organic Growers Guide” by Kath Irvine, to be released soon) Don’t be in a hurry to plant out your vegies. Wait till the soil warms and the danger of frost is over. There is no harm done if you prick your seedlings into bigger pots and keep them under cover. Planting earlier doesn’t mean an earlier crop. In fact, if your young plants are hit with a spell of cold weather, a frost or random hailstorm you could lose or weaken them. If you are planting out now, make sure you keep your babies protected from the mad Spring weather. [Here’s hoping for a good Spring this year, though – Ed] Feed onions, garlic and roses with liquid seaweed, fish fertiliser or comfrey. The best liquid feeding days are 3 days before or after the full moon. Keep onion, garlic and carrot beds weeded. If you plant early potatoes, make sure they are protected from frosts. Herbs should all be planted out now. Plant some beneath your roses for good pest control. Plant citrus trees. Citrus have shallow feeder roots so make sure they are planted into good compost and mulched well to cope with Summer. I prefer to mulch citrus as opposed to growing a living mulch. They do better if they have no competition around their feeder roots. Citrus are hungry trees. Keep them fed once a month and be rewarded with glossy green leaves and bright fruit. Thin stonefruit. This is very important to get more quality fruit. Foliar feed stonefruit if you have a history of brown rot. Feed berries. Mulch under strawberries to keep fruit clean. Watch for botrytis (grey mould) on your strawberries at this time of year. Protect them by keeping them strong with regular seaweed sprays. Watch for aphids on new growth. Keep up your slug and snail watch. Use BT spray to manage diamond back caterpillar and cabbage white butterfly. Keep checking codling moth traps. Codling moths are grey-brown moths with fringes on their back wings. They fly at night and during the day rest on the trunk of your apple trees. Females lay up to 50 eggs on fruits or leaves. These eggs hatch within a fortnight and the pinky caterpillars bore into your fruits. When they are full (and your apple is holey!) they crawl down the tree to find a cosy spot to spin a cocoon. There they stay till Spring. Trim your hedges. Keep a nice layer of fresh Spring growth around the outside. Deadhead flowering plants to keep them flowering longer. MOON PLANTING GUIDE – OCTOBER 2007 last quarter 3rd - new moon 11th - first quarter 19th - full moon 26th During the month the moon moves through all the signs of the zodiac. Cancer, Pisces & Scorpio are the most fertile, then Libra, Taurus & Capricorn. Gemini, Leo and Virgo are the least fertile. Leaf crops (including garlic and onion) are favoured from new moon to first quarter. Sow salad greens, brassicas, silver beet, celery, parsley, spinach, lettuce, celery, herbs, spinach, cress, silverbeet from the 12th-15th and 18th. Flower, fruit and seed growth are favoured from first quarter to full moon. Sow tomatoes, beans, zucchini, peas, pumpkins, sunflower, eggplant, capsicum, corn, cucumber, flowering annuals on the 20th and 23rd-24th Root growth is most vigorous from full moon to last quarter. Sow carrots, beetroot, potatoes on the 1st, 27th, 28th and 30th. These are also good days for planting bulbs, corms, trees and shrubs. From last quarter to new moon, no planting is recommended. Weed, prune and cut firewood in barren signs (6th-10th). Spread compost in fertile signs (4th, 5th) Ascending moon: 3rd-17th, 30th-31st. Descending moon: 1st-2nd, 17th-29th The ascending moon gets higher in the sky, similar to the sun in spring and summer. The earth “breathes out” and growth flows upwards more strongly to fill the plant with vitality. This is a good time for sowing seeds. The descending moon is similar to the sun’s path in autumn and winter. The earth “breathes in”, drawing the etheric forces back below the surface to activate the lower parts of the plant, especially the roots. This is a good time for cultivation, making and applying compost, harvesting root crops, cutting firewood and pruning fruit trees. Nodes are on the 8th at 9am and the 22nd at 10pm when the moon crosses the path of the sun (the ecliptic). No garden work is recommended for at least a few hours either side. 2008 ORGANIC RIVER FESTIVAL The festival is now only four months away, to be held on the Saturday and Sunday of Wellington Anniversary weekend, 19 and 20 January. This is our biggest event of the year, our main chance to put across our message of Healthy Soil – Healthy Food – Healthy People. It also helps us to fill our coffers so that we can cover our expenses for the year ahead. We rely on the generous donations of you, our members, whether by way of plants, produce, baking or staffing the stall. Seed-grown plants will need to be started soon to ensure vigorous, well-rooted plants for January. Please also start thinking about any cuttings or divisions you would like to take. Plants in standard sized pots or potting bags are preferred, labelled with the name. Berry plants and herbs are popular items. We are still on the lookout for raffle prizes. If you have any suggestions, please contact a committee member. The next committee meeting will be held on Monday 8 October at 10am with Liz Baucke, 169 McLeavey Road, Levin. All members are welcome to attend. |
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Soil & Health
Association of New Zealand Inc (est 1941) Healthy
Soil - Healthy Food - Healthy People |
