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

chart shows different growing mediums’ ability to hold positive charges that are ready for root uptake. Note the zero CEC of perlite and rockwool. Roots must be constantly bathed in nutrients. Other mediums do not provide a constant flow of nutrients and the CEC regulates the ability to hold a positive charge to make nutrients available for root uptake.
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Containers

Ceramic containers are durable but heavy.
    Container preference is often a matter of convenience, cost, and availability. But the size, shape, and color of a container can affect the size and the health of a plant as well as the versatility of the garden. Containers come in all shapes and sizes and can be constructed of almost anything–clay, metal, plastic, wood, and wood fiber are the most common. Cannabis will grow in any clean container that has not been used for petroleum products or deadly chemicals. Clay fiber and wood containers breathe better than plastic or metal pots. Heavy clay pots are brittle and absorb moisture from the soil inside, causing the soil to dry out quickly. Metal pots are also impractical for grow rooms because they oxidize (rust) and can bleedoff harmful elements and compounds. Wood, although somewhat expensive, makes some of the best containers, especially large raised beds and planters on wheels. Plastic containers are inexpensive, durable, and offer the best value to indoor growers.
    Rigid plastic pots are the most commonly used containers in grow rooms. Growing in inexpensive, readily available containers is brilliant because they allow each plant to be cared for individually. You can control each plant’s specific water and nutrient regimen. Individual potted plants can also be moved. Turn pots every few days, so plants receive even lighting and foliage will grow evenly. Huddle small, containerized plants tightly together under the brightest area below the HID lamp, and move them further apart as they grow. Set small plants up on blocks to move them closer to the HID. Individual plants are easily quarantined or dipped in a medicinal solution. Weak, sick, and problem plants are easy to cull from the garden.
    Grow bags are one of my favorite containers. Inexpensive, long-lasting grow bags take up little space and are lightweight. A box of 100 3-gallon (13 L) bags weighs less than 5 pounds (2.3 kg) and measures less than a foot square. One hundred 3-gallon (13 L) grow bags can be stored in two 3-gallon (13 L) bags. Imagine storing 100 rigid pots in the same space!

White pots reflect light and heat. Black pots set inside the white pots keep roots in a dark environment

Grow bags are economical, lightweight, and reusable.

The potting soil bag can also be used as a container.

Woven coco fiber pots from General Hydroponics breathe well, do not compact, can be used several times, and are biodegradable.

Containers on casters are easy to move and stay warmer when up off the floor.
     
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Containers must be:
Clean
Have adequate drainage holes
Big enough to accommodate plant
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    Grow bags are very easy to wash and reuse. Empty out the soilless mix and submerge bags in a big container of soapy water overnight. Wash each one by hand the next day and fill with soil. I like them much better than rigid pots because they are so practical.
    The potting soil sack can be used as a container. The moist soil inside the bag holds its shape well, and the bags expand and contract with the soil, lessening the chance of burned root tips that grow down the side of pots.
    Fiber and paper-pulp pots are popular with growers who move their plants outdoors. The bottoms of the pots habitually rot out. Painting the inside of the fiber container with latex paint will keep the bottom from rotting for several crops.
    Set large pots on blocks or casters to allow air circulation underneath. The soil stays warmer and maintenance is easier. Planters should be as big as possible but still allow easy access to plants. The roots have more room to grow and less container surface for roots to run into and grow down. With large pots, roots are able to intertwine and grow like crazy.

Planting directly in the floor of a basement or building gives roots plenty of space to expand.
    Grow beds can be installed right on the earthen floor of a garage or basement. If drainage is poor, a layer of gravel or a dry well can be made under the bed. Some growers use a jackhammer to remove the concrete floor in a basement to get better drainage. An easier option