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Article 3-4 Rules of Green Thumb

  1. When you receive your babies (cuttings or clones): Tender clones require fluorescent light, 1-4 inches above the top of the plant. When kicked (put into bloom) the 1000 watt light should be 4 ft inches above the plant the first day, watch plants for first 24 to 48 hours of okay lower 1 ft a day until desired height.

    Tip #1: The babies require low levels of N and K, but use large quantities of P. The numbers on a bottle of food describe what levels of NPK (in that order) are contained in the bottle.

  2. Plants grow in three stages:
    • Rooting stage: just clipped from the mother plant and developing roots.
    • Vegetative stage: green leaf growth and height.
    • Flower stage: the plant is producing fruit or buds.
    • Rooting stage: The baby enjoys humidity; misting is done with water alone, and do not over-water.
    • Vegetative stage: The plant likes a misting of water, three to three and a half hours before the lights turn on. The light is left on for 18 hours and shut off for six hours.
    • Flower stage: The plant also likes a misting of three hours before the light comes on. The light is left on for 12 hours and shut off for 12 hours.

    Tip #2A: The best time to harvest your garden is after a full day without water. It is better to exhaust air, than to have a fan directly blowing on your plants. Light, air, heat and friction break down the chloroform in the leaves.

    Tip #2B: Also, two weeks before harvest, no plant food is to be added to the water reservoir. This is done to remove the fertilizer out of the fruit or flower and the plant itself, known as flushing the plant.

  3. Always use tepid water at 60° to 80° Fahrenheit; not too cool or too hot. The reason for this is that the water penetrates the soil more efficiently and in your hydro setup, the nutrients are absorbed more easily by the plant. It's best not to shock the plants; would you rather jump into a cold or warm swimming pool? Check the condition of the plant's soil first before watering. It is better to under-water, than to over-water (you can easily kill a plant by over-watering).

    Tip #3A: The most efficient way to replicate the movement of the sun, e.g., the movement from east to west, is using a Sun Circle, Pro Track or the Light Rail. These methods are the best technology available right now. For plants to receive more light, rotating plants every few days would solve some of the problem. Otherwise the plant tends to grow towards the light, up and not out, severely shading the rest of the plant and garden.

  4. Nutrients: Know Your Letters
    Nitrogen: (N) Important in the vegetative stage, for leaf growth. Lack of N, would show poor leaf development and the plant itself would be soft and weak.

    Phosphorous: (P) Important for root and flower growth. The plant needs extra P at both the rooting and flowering stages. Lack of P would show signs of stunted or slow growth.

    Potassium: (K) Important for helping plant intake nutrients and regulating the intake. Lack of K would show irregular growth and not resisting disease (a sick plant). Give less K at flowering stage because excessive K slows fruit production.

    Calcium: (Ca) Important to filter other nutrients, aiding absorption and balancing an otherwise low pH level (over acidity). Ca is mostly used in the vegetative stage with N and is decreased in flowering.

    Magnesium: (Mg) Important in the plants production of chlorophyll (green) and in it's use of light. Lack of Mg shows more likely in flowering and you can tell when the leaves turn yellow, while leaf veins remain green.

    Sulfur: (S) Is used in small amounts by the plant. Lack of S would be recognized when new leaves turn yellow.

    Iron: (Fe) Like Sulfur, used in small amounts, and has same deficiency symptoms. Alkalinity (a high pH) will prevent the plant from absorbing Fe.

    Molybdenum: (Mb) Acts as an electron carrier in conversion of nitrate to ammonium, and is also essential for N intake.

    Boron: (B) May be required for carbohydrate transport in the phloem. Usually deficient in the soil outside. To much will kill the plant.

    Tip #4: Giberellic acid can be used to stimulate fast growth of all plants. It will elongate stems and increase flower or fruit size.

  5. pH Balance
    pH is a way of showing if your water is acidic or alkaline. pH is measured on a scale from 1 to 14. 1 is most acidic 7 is neutral 14 is most alkaline

    The average plant grows best in pH levels between 5.8 to 6.5. If pH is too low (acidic) the nutrients are chemically bound by acid salts and roots are unable to absorb nutrients. If pH is too high (alkaline) it will cause toxic salt build up and limit the root intake of water and food.

    Tip #5: pH is always tested after food is added to water, as food or nutrients will change the pH level. There are pH meters available on the market to measure pH. The pHMS, Continuous Monitoring System is available at your indoor gardening supply centres.

    Fertilizers are also known as food or nutrients for plants. When improperly stored, fertilizers will affect the potency of the vitamins and minerals contained in the nutrients. Store fertilizers in a cool, dry, dark and clean place.

    Application of plant food varies from stage to stage of a plant's life. There are CMS (Continuous Monitoring System) meters to measure how much food content is in your water.

    Average readings indicate the plant stages at which they occur:

    PPM = 4 - 6
    Ms = 8 - 12
    PPM = 8 - 11
    Ms = 16 - 22
    PPM = 10 - 14
    Ms = 20 - 28

    Symptoms of over-fertilization:

    leaves appear to be curled under, or
    leaves turn dark green with browning or burning at leaf tips

    Solution: Water with pH water for a few days. After plant appears to have improved begin spraying or mix in watering container and feed with diluted food.

    Tip #6: The readings on your meter may vary, so does the amount of food required for the plants. Keep a close check on the plants' appearance, and go from there. In time, you'll have developed an eye for how healthy a plant should look in all it's stages.

  6. Bugs and Fungi
    "Cleanliness" is the key to bug and fungus prevention. Washing of hands is important before and after handling diseased plants. Do not walk outside, then directly into the grow room. Always have your grow room clothing prepared, ready to put on, then remove when leaving. This is important, especially if: you happened to walk across a lawn covered in rust (rust is a rust-colored fungus), pet the dog that just came in from the garden, or touched the spider mite-infested philodendron in the living room. Be sure to check the following for potential problems: cleanliness, soil, climate or temperature, and animals that are in contact with plants. To help control these problems, surround plants with forced air circulation. This environment makes life miserable for bugs and fungus. When using chemicals, never spray three weeks before harvest, or the fruit or vegetables will taste tart and bitter. Plants must also be water misted a few days after the day you spray in order to get rid of the dead bugs and chemicals.

    Tip #7: The temperature of the grow room should range between 85-95 degrees Fahrenheit depending on CO2. If you are using CO2, increase to a higher temperature, and provide good air intake and exhaust.

    A Tip About Flowering
    The leaves of a plant are the only part that can carry the flowering signal. The mechanism that causes this signal is an interesting process. Plants contain very specific color pigments, two of which are called phytochrome (red) Pr, and Phytochrom (far red) Pfr. Pr absorbs light at 660 NM. Pfr absorbs light at 730 NM. A long, dark period allows the Pfr to dissipate and causes hormonal change that makes the plant flower. For production purposes, give the plant a good start by diminishing the Pfr; induced flowering is started with 36 hours of darkness before the first 12 hours of light and 12 hours of dark.

    Plant Stress
    Stress in plants is caused by imbalances in the plant's chemistry. Water stress in plants causes *abscisic acid to build up and close down the stomata. General stress in plants causes ethylene to start diffusing in the cells.

    Plants prefer to have a steady, stable environment in which to grow. Any unusual event in the plant's life will change its internal chemistry and result in diminished growth. Some causes of stress are:

    1. Lack of water or too much water.
    2. Irregular light cycles - changes the hormonal balance
    3. Plant damage - causes the plant to change its local chemistry to repair the damaged site
    4. Damaged roots through transplanting. Damaged root hairs and roots cause the plant to change its chemistry and to divert root structures. Roots do not repair themselves.
    5. Environmental extremes and diseases. This type of plant stress is treated with an application of Vitamin B1. This will stabilize the plant chemistry.
      • Stress can cause a plant to age and flower prematurely.
      • Stress can also cause a female plant to produce viable seeds without being fertilized.
      • Plant stress will also be indicated by poor growth.

    * Abscisic acid is also part of the plant's aging process. It controls seed development and causes the stomata to close under water stress.

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