Marijuana Horticulture: The Indoor/Outdoor Medical Grower's Bible

heat.

This large clone has been rooting for a week. The expert grower makes sure the climate is perfect, so clones suffer no stress.

Strong clone in an aeroponic clone garden has a mass of roots and is ready to plant.
    Step Seven: Clones root fastest when humidity levels are 95-100 percent the first two days and gradually reduced to 80-85 percent during the following week. A humidity tent will help keep humidity high. Construct the tent out of plastic bags, rigid plastic, or glass. Remember to leave openings for air to flow in and out so little clones can breathe. If practical, mist clones several times a day as an alternative to the humidity tent. Remove any sick, rotting, or dead foliage.
    Cut leaves in half to lower transpiration surface and to keep them from overlapping. Moisture that could foster fungus is often trapped between overlapping leaves. Keep the grow medium evenly moist so there is enough moisture to prevent cut leaves from bleeding out plant sugars that attract diseases.
    Step Eight: Clones root faster when the growing medium is a few degrees warmer than the ambient air temperature. A warmer substrate increases underground chemical activity, and lower air temperature slows transpiration. For best results, keep the rooting medium at 75-80°F (24-27°C). Growing medium temperatures above 85°F (29°C) will cause damage. Keep the air temperature 5-10°F (3-5.5°C) cooler than the substrate. A warmer growing medium coupled with cooler ambient temperature slows diseases and conserves moisture. Misting clones with water also cools foliage and slows transpiration to help traumatized clones retain moisture unavailable from nonexistent roots.
    Put clones in a warm place to adjust air temperature and use a heat pad, heating cables, or an incandescent light bulb below rooting cuttings.
    Step Nine: Some cuttings may wilt but regain rigidity in a few days. Clones should look close to normal by the end of the week. Cuttings that are still wilted after seven days may root so slowly that they never catch up with others. Cull them out, or put themback into the cloning chamber to grow more roots.
    Step Ten: In one to three weeks, cuttings should be rooted. Signals they have rooted include yellow leaf tips, roots growing out drain holes, and vertical growth of the clones. To check for root growth in flats or pots, carefully remove the root ball and clone to see if it has good root development. For best results, do not transplant clones until a dense root system is growing out the sides and bottom of rooting cubes.
    Cuttings are always strong and healthy-looking after you take them. After five or six days, leaves may start to change color. Leaves stay small and often turn a deeper shade of green. After about a week, lower leaves may start to yellow if their nutrient levels dissipate.
    A week after being taken, clones’ stems will develop stubby callused roots called primordia. The primordia are semi-transparent to white and should look healthy. Clones produce very little green growth during this process. Once the root and vascular transport system is in place and working properly, clones are able to experience explosive growth with the proper care.
    Rooting clones can handle increasingly more light as roots grow. Move the fluorescent lamps to two to four inches above plants when roots form. Fertilize with a mild fertilizer solution when all clones have started vegetative growth.
    Any sign of slime, pests, or disease means there are problems, and clones should be removed from the garden.
    Transplant only the strongest, well-rooted clones. (See “Transplanting.”) Slow-rooting clones should be kept in the cloning chamber or culled out. Do not move clones below bright light until they have fully developed root systems. Once transplanted, clones are ready to harden-off (see “Transplanting”).

This cutting needs to grow a bigger root system before transplanting.

This mass of roots is from a clone with a split stem; the outer layer of the stem was scraped away to expose the cambium.

Plenty of roots are growing from this clone rooted in a Jiffy cube. It is ready to transplant.
     
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Sequence of cloning for sex

    1. Make 2 cuttings

    2. Label each cutting

    3. Give 12 hours of light while rooting

    4. Cutting will determine sex in 2-3 weeks
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Cloning the apex of the tip

Swiss cloning expert is removing the tip of a mother plant to clone in an agar solution. Such clones are easy to maintain for long