1. Noting or pertaining to a class of chemical compounds that formerly comprised only those existing in or derived from plants or animals, but that now includes all other compounds of carbon.
2. Characteristic of, pertaining to, or derived from living organisms: organic remains found in rocks.
[FONT="]3. Of or pertaining to an organ or the organs of an animal, plant, or fungus.
[/FONT][FONT="]1. Soil texture[/FONT]
[FONT="]Soil texture refers to the size and proportion of the mineral particles in the soil. Specifically, it refers to the relative percentages of sand, silt and clay. Sand is the largest of these three particles. It is easily visible with the naked eye. Clay, on the other hand, is much finer (you need a microscope to see the particles). Silt is in between the two extremes.
Depending on the proportion of each type of mineral, soils can be divided into four groups: sandy soils, silty soils, clay soils and loams. Each group has distinct features.[/FONT]
[FONT="]1.1 Sandy soils (light soils, yellow soils)[/FONT]
sand.jpg 54.05K 450 downloads
[FONT="]Sandy soils[/FONT][FONT="] [/FONT][FONT="]consist mainly of coarse sand. Soils of this type are easy to work and warm up quickly in spring. They are well aerated and have good drainage, but are subject to leaching (of water and minerals). They are usually lacking in nutrients and tend to be acidic.[/FONT]
[FONT="]The grains of sand are visible to the naked eye. The soil runs between your fingers like sugar. It is very gritty and rough.[/FONT]
[FONT="]The soil doesn’t clump together easily, and breaks apart when prodded with a finger.[/FONT]
[FONT="]You can improve the structure of sandy soils by regularly adding organic matter in the form of compost or composted manure. It is best to work these amendments into the soil in early Spring, because working sandy soils in the Fall promotes erosion. Adding basalt to these soils is one way of improving their ability to retain water and minerals. To improve the structure of sandy soils, it is best to work them as little as possible.[/FONT]
[FONT="]1.2 Silty soils[/FONT][FONT="] [/FONT]
silt.jpg 27.71K 477 downloads
[/FONT] [FONT="]Silty soils consist mainly of fine sand and silt. Rain and watering tend to form a crust on the surface of this type of soils, making it impossible for water and air to penetrate. They also compact very easily, suffocating the plants’ roots and the organisms in the soil.[/FONT]
[FONT="]The soil looks powdery or floury. The soil feels soft.[/FONT]
[FONT="]The soil is very soft and slippery, like soap. It can be rolled into a coil, which breaks apart if you try to bend it. The soil isn’t very sticky.[/FONT]
[FONT="]You can improve the drainage and aeration of silty soils by adding large amounts of organic matter in the form of compost or composted manure. It is best to work these amendments into the soil in late Fall.[/FONT]
[FONT="]1.3 Clay soils (heavy soils, clayey soils)[/FONT]
clay.jpg 39.56K 399 downloads
[FONT="]Clay soils contain over 25% clay. These are usually rich soils with good water- and nutrient-retention properties. However, they are poorly aerated and drained and tend to be alkaline. In addition, they are difficult to work, slow to warm up in Spring and easily compacted. [/FONT]
[FONT="]The soil contains very hard lumps that are hard to break apart. [/FONT]
[FONT="]The soil is very sticky; it is smooth and shiny. The soil is easy to mould; it can be rolled between the fingers into a long, flexible coil.[/FONT]
[FONT="]You can improve the structure of clay soils by adding organic matter in the form of compost or composted manure. It is best to work these amendments into the soil in late Fall. Poorly drained clay soils can also be amended by adding sand. Some clay soils are very high in sodium, which prevents mineral particles from forming aggregates. The structure of such high-sodium soils can be improved by working in gypsum (if their pH is neutral or alkaline) or lime (if their pH is acidic).[/FONT]
[FONT="]Compact clay soils can be turned over with a fork in Fall. Over the course of the Winter, the large clumps will be broken down by alternating freeze-thaw cycles. In Spring, you can further break them down into small aggregates to obtain a granular structure. Avoid overworking clay soils that have a good structure.[/FONT]
[FONT="]Clay soils should never be worked when they are too dry or too wet. They become hard and cracked during dry spells, and are easily compacted during wet spells. The best time to work such soils is when clumps break apart when squeezed.[/FONT]
[FONT="]1.4 Loams (loam, loam soils)[/FONT]
loam.jpg 26.96K 458 downloads
Loam soils contain about 40 to 60% sand, 30 to 50% silt and 15 to 25% clay. These are excellent soils for growing plants, because they are well balanced in terms of aeration, drainage and water and nutrient retention. They are also highly fertile. These soils are suited to growing most plants (weed).
The soil is a bit gritty. The clumps will not break if handled carefully.
If rolled between the fingers, the soil will form a coil that cracks slightly
[FONT="]2. Soil structure[/FONT]
[FONT="]Soil structure refers to the way in which the sand, silt and clay particles are arranged relative to each other. [/FONT]
[FONT="]In a well structured soil, the particles of sand and silt are held together in aggregates (small clumps) by clay, humus and calcium. The large empty spaces between the aggregates (macropores) allow water and air to circulate and plant roots to grow down into the soil. The small empty spaces (micropores) hold the water the plants need. This “ideal” structure is called granular, or crumbly.
microscopic.jpg 22.94K 459 downloads
[FONT="]Soil with a granular structure is the best type of soil[/FONT][FONT="]. It holds water and nutrients well, has a good drainage, good aeration, good plant root system development. The soil is easy to work, it warms up quickly in Spring, good biological activity, it resists erosion and compaction.[/FONT]
[FONT="]Clay, sandy and silty soils rarely have an ideal structure. They can be improved, however, by working in amendments. Regularly add organic matter (compost or composted manure). Encourage [/FONT][FONT="]biological activity in the soil[/FONT][FONT="]. Correct the pH as necessary. Avoid overworking the soil. Hoe the soil or turn it over lightly. Use mulch.[/FONT]
[FONT="]2.1 Jar test[/FONT]
jar test.jpg 14.88K 387 downloads
[FONT="]Place one or two cups of soil in a clear glass jar that holds about 1 litre and add water almost to the brim. Shake the mixture vigorously for a few minutes, then let it stand for at least 24 hours, because the clay may take several days to settle (it will settle more quickly if you add 2 tsp reg. salt).[/FONT]
The mixture will gradually form layers, with sand on the bottom of the jar, silt in the middle and clay on top. Clay is lighter, sand heavier. Organic matter will float to the surface. You can calculate the percentage of each element according to the depth of each layer.
Sandy soil: 70% or more sand, from 0 to 30% silt and O to 15% clay
Silty soil: 0 to 20 % or more sand, 80% silt and 0 to 15% clay
Clay soil: 0 to 40 % or more sand, 0 to 45% silt and 25% or more clay
Loamy soil: 40to 60% or more sand, 30to 50ù silt and 15 to 25 % clay.
sandy soil jar.jpg 19.19K 364 downloads
Sandy soils are are very common near mountain foothills, along rivers and streams and certain coastal areas. Sandy soils are typically comprised of approximately 80 - 100% sand, 0 - 10% silt and 0 - 10% clay by volume. Sandy soils are light and typically very free draining, usually holding water very poorly due to very low organic content.
loam soil jar.jpg 18.13K 364 downloads
Loam soils are common in valleys and flat areas (flood plains) surrounding rivers and streams. Loam soils are typically comprised of approximately 25 - 50% sand, 30 - 50% silt and 10 - 30% clay by volume. Loam soils are somewhat heavier than sandy soils, but also tend to drain because of their rather low organic content.
clay soil jar.jpg 17.91K 355 downloads
Clay soils are very common in certain areas, particularly around urban areas where fill soils have been used to establish grade in subdivisions and developments. Clay soils are typically comprised of approximately 0 - 45% sand, 0 - 45% silt and 50 - 100% clay by volume. Clay soils are not typically free draining, and water tends to take a long time to infiltrate. When wet, such soils tend to allow virtually all water to run-off. Clay soils tend to be heavy and difficult to work when dry.
2.3. Visual Test.
- If the color is dark brown, black, it’s rich in vegetable debris, more or less decomposed. Acidic. Rich in humus.
- If the color is towards the white, if it gets whiter as you dig, the soil is rich in limestone (chalky). This is not dolomite lime (!). Alkaline.
2.4. Manual test.
- make a ball of soil with your hand and drop it. If it doesn’t break when hitting the floor, it’s clay. Clay pH varies also but tend to be alkaline. Clearer soil (with Calcium) is usually alkaline.
- you try to make a ball but can’t (crumbly). The soil is rich in sand. Sands are often alkaline.
- you can make a ball which breaks in small/smaller pieces when hitting the floor: this is ideal free top soil. Find it under trees, bushes (protected from rain wash) but not oak or pine (acidic). Check pH when using outdoor soil to be sure.
2.4. Hole Test.
Dig a hole (1-2 ft deep). Fill it up with water and let it drain. If it drains in 3-4 hours, the soil drains well. If it’s 5-12 hours, drainage is medium. If there’s still water in the hole after 12 hours, your soil retains water too much.
pH: It’s the hydrogen potential. The more hydrogen ions there are, the more acidic the soil is.
This scale is exponential. For example, a soil with 6 for pH is 10 times more acidic than a soil with a pH of 7. A soil with a pH of 5 is 100 times more acidic than one with a pH of 7.
Buy a cheap pH meter and make sure the pH is ok (not necessary if you use store bought soil and old manures, compost). Mj likes approx. 6-6,8.
An inadequate pH can cause certain elements to not be accessible to the plant (even if they’re in the soil), and also cause several elements (like aluminium, iron etc…) to become toxic. It can also hurt the benef. micro-org. in the soil and develop harmful mushrooms. But outdoors, pH shouldn’t be a problem if you bring most of the soil. Many GC growers don’t check the pH. PH is not a big outdoor issue. Nute burn due to excess ferts is more common than nute lock due to pH problems. If burned, she won’t be hungry –if still alive- even if the pH is good. So go easy on the nutes, and check the pH before planting if you're unsure.
Acidic soil: Amend it with dolomite lime or wood ashes (=alkaline).
Alkaline soil: Amend it with sulfur, iron sulfur, pine needles (=acidic).
3. Other interesting organic amendments (besides manures, meals, worm castings...):
- Seaweed: Used forever by people living near the waters. Red seaweed was used before to lower acidity. Has all trace elements. Use directly in soil (decomposes quickly, no burn) or compost it. Rince if used fresh (salty). Contains Potassium (K). Gives a nice structure to the soil (binds it together). Used to make light soils heavier (thicker). Use 1-1,5 kg/m2.
- Basalt : Comes from volcanoes. Has all trace elements (Calcium, Potassium, Iron...). It has 10% of Magnesium (can replace Epsom salts) and Silica. Very rich, excellent amendment. Basalt thickens sandy soils, and lightens heavy soils (clay). Use 600g/m2. For best results, place in compost heap.
- Rock phosphate: Comes from ore-mining. Has a lot of Phosphorous (P) and Calcium. The calcium reduces acidity. Half as strong as lime.
- Wood ashes: The high Calcium reduces the acidity. Contains Potassium too. Used in Spring or in the compost pile. Don’t use on seedlings. Works fast but effect is not long. Don’t use too much or there will be excess Lead and Cadmium (toxic). Use 500g/m2.
- Lime: Use dolomite lime for Mj (has Magnesium which ashes and other limes don't). The Calcium lowers acidity. Calcium makes clumps with heavy clay soils and helps make them lighter. The effect can last up to 3 or 4 years according to how much was added and the type of soil. For sandy soils, put the lime in Spring. For other soils, the best time is Aug-October. Wait at least one month before fertilising (manures etc…) a soil that was amended with lime. Dosage: 1 ounce per gallon.
- Compost: In a compost pile, billions of micro-organisms who decompose elements live and die. This decomposition process is constant in nature. You can find natural compost outdoors (test the pH to be sure). Making your own compost pile just accelerates this natural process for making excellent organic fertilizer. Compost is not top soil or potting soil (compost is richer, and is a fertilzer). Compost takes 1 year to be ready approx.
Micro-organisms need humidity, heat, airing out and food. A good compost is as wet as a soaked sponge. Too much water will drown the m-o, taking away their air. Keep a good level of moistness/humidity by alternating layers: humid things, dry things. Don’t add very bulky things (break them apart before adding). Turn over your pile to eliminate any excess humidity (good airing out). Cover the pile if there it rains a lot. Place wooden stakes in the pile as you add layers. Later, take the stakes out (to air out).
Make sure the bottom of the pile is sawdust, hay, wood shavings so air circulates from the ground into the pile (don’t do a compost on a cement platform: won’t work). Use a medal bar to air it out too.
The recommended temperature is 50°C. To attain this temperature, the pile should be at least 1 m3. If smaller it won’t work. You can buy a compost thermometer (long).
Start the pile with hay, scrub, shavings, shredded leaves…
DO NOT ADD: cat and dog manures, meat products, bones, fats (butter…), chemicals (to acc. process).
Add layers of:
- fruits and veggies (cut if big size).
- coffee filters, teabags, crushed eggshells.
- old bread, rice, noodles.
- grass, hay, ditchweed (don’t use gas lawn mower grass –contain gas-). I don’t know about electric ones (ok?).
- farm manures: leave 6 months under stable (no rain) to use. Or buy “composted” manure, and use 1-2 months after placed. Separate from roots with good pH (not hot) soil mix. Do not use fresh manure directly.
- Mushroom compost: Contains all trace elements. Ideal for heavy clay soils. Contain a lot of Gypsum. Very rich in Calcium. Using this type of compost will cause a deficiency in Magnesium. Use only for very acidic soils.
- Hop pulp: If you live next to a beer brewery. Has a lot of Phosphorous and many trace elements and organic elements. Use as mulch or in the soil mix. 1-1,5 kg/m2.
Using organics encourages micro-biological life. Organic amendments do not pollute the Earth and the ground water as chemicals do. Soils without micro-organisms are eroded or compacted by the chemicals with time. M.-o. hold elements, air out the soil, and protect plants from diseases. Organic soils protect and feed the plant without buying many things from the store (chemical ferts, pesticides). Even if you don't have time/place to compost, add some humus/compost (you find outside), some composted manure and meals to have an organic grow. Then, feed the micro-organisms and the plants with organic teas. Your buds will taste better and keep longer.
Edited by Corto Malteze, 09 February 2009 - 10:29 AM.