Learning how to grow can be overwhelming, and entire crops can be lost if not done right. This web page and video is meant to show a method of growing that is useful for the home-grower.
For a complete guide on growing, Jorge Cervantes wrote The Cannabis Encyclopedia. It is available on Amazon in soft and hard-cover. The links are to the right.
First, we need to start some seeds. Place some seeds in a wet paper towel, and place them in a zip-top plastic bag. Make sure the paper towel is not over-saturated with water, that could kill the seeds. If you are able to let the bag of seeds hang, the taproot will grow straight down.
Fill up a container, or plastic cup with soil. Be careful with some off-brand plastic cups. They can leak a chemical taste, and those chemicals can affect the plant. Poke a hole or two on the bottom of the cup to allow for drainage, and give it some water. Reverse osmosis, or distilled water should be used if your tap water has too much chlorine or contaminants. With something like a toothpick, make a hole in the middle of the of the wet soil, and gently place the taproot down the hole. Lightly bring the soil around the root (as shown in the video).
Soil is expensive to ship. It is usually a lot less at gardening and hydroponic stores
Keep seedlings under 18 or 24 hours of light, but what type of lights? LED lights have taken over the home-grower market. They produce a lot less heat, and use a fraction of the energy. Metal halide and high pressure sodium lamps need to be cooled down (usually with air-conditioning), while many new LED lights have their own built in fans!
Plants under 18 or 24 hours of light tend to grow better with light on the blue spectrum. Metal halide bulbs are bluer, and were typically used for vegetative growth. In Jorge Cervantes' encyclopedia, he recommended trying 6500oK bulbs if you are looking for LED. Just for comparison, metal halide lamps range a lot, but growers often use 4200oK. The blue spectrum bulbs were also supposed to help increase the number of female plants from regular seeds. It may also help reduce hermaphrodites.
When it is time for flowering, the plants prefer light on the red spectrum. As well as the lights to be at 12 hours on and 12 hours off. High pressure sodium lamps, often rated at 2100oK are used. The LED option is to use full spectrum grow lights.
In most soils, nutrients are needed. I have had great luck with FoxFarm and Advanced Nutrients. The FoxFarm nutrients will need ph adjustment, and I have not needed to adjust the ph with Advanced Nutrients.
If you want to keep it very simple. Use as directed:
There is much more to nutrients You can add on extra nutrients for a massive harvest, or just keep it simple with base nutrients. I do prefer adding on extra nutrients such as:
Learn more at https://www.advancednutrients.com/
Once the cotyledons on seedlings have started to turn yellow, the plants will need nutrients!
As the seedlings grow, remove the lower branches to make the plant grow taller. When the seedlings need watering every day, then it is time for them to be transplanted into a bigger home.
Grow bags are a great way to grow. They are inexpensive, reflect light, keep the roots cooler, and reusable.
Mycorrhizae and beneficial bacteria are helpful to reduce transplant shock. I use this one per week for the first month, and when transplanting to a larger container.
As the plants grow larger, keep removing the bottom branches. Don't let the plant waste time on growing parts that are not needed. Some of this space will need to be filled with soil, especially if they will be moved outdoors to flower. This will help stabilize the plants from the wind, which could damage roots and make the plants lay flat on the ground.
Once your plants have reached the desired size, it is time to make them start to flower.
If you are growing indoors and tents, 12 hours of light on and 12 hours of light off will be needed. Usually within 2-3 weeks, signs of flowering will show.
The problem with growing weed, is that is smells like weed! If you don't want to smell it all the time, get a couple of carbon filters. If you are using a grow tent; hook one fan/filter setup going into the tent, and the other going out of the tent. Add extra fans if needed to circulate the air, or if you place the duct fan just right; then that might be enough.
I personally vegetate the plants indoors under 18 hours of light, and them let them flower outside. The area they flower in only gets about 8 hours of direct sunlight, and the rest of it is shade. Under this type of condition, they will be done flowering about the same amount of time indoor batches will take. I am able to harvest every 3-4 weeks using this method.
During mid flowering, the fan leaves should be removed. This helps prevent mold growth, and lets the plants spend their energy on flower and trichome growth.
Before cleaning up
After cleaning up
Once the white (or pink) pistils have wilted down, and the trichomes have turned white. Then it is time to harvest. You can harvest early if you need to while the trichomes are still clear, but the effect will be less psychoactive.
Not even close to being ripe yet
Fully ripened flower
Flushing agents are necessary for hydroponics and coco-coir about 5 days before harvesting; then nothing but water. If you are ever unsure if you need a flushing agent or not, consult your local hydroponic store.
For soil users, give plain water for the last 10-14 days if you don't want to mess with a flushing agent. The only times you will need to flush soil is if you need to harvest soon (5 days), or if your soil is very rich in slow-releasing nutrients.
If you ever smoked buds that never turns into a white ash, and it stays a black resinous mass, then the weed was not flushed enough. Unflushed weed has residual metals and nutrients in it that will not burn.
When it is harvesting time, clip all of the trim off. Let the trim dry on some parchment paper. Hang the flowers upside down. Use a small fan to keep the air circulating, and to prevent mold growth. Drying in a dark place is ideal, THC is light sensitive.
Textbooks recommend that the freshly harvested flower needs to lose 75% of its weight while drying before curing in a jar. After a few harvest, you will know by the way the buds feel when they are done drying. They should not feel cold or moist at all.
If the buds start to smell like hay, then they dried too long. If that happens, pack the buds in an air-tight jar. Some of the terpene aroma might return in a week or two
When you are ready to cure the buds. Place the clipped off buds into glass jars. Air-tight jars will keep the buds the freshest for the longest time. Screw-top jars work fine too, but they tend to let the weed dry a little too much.
If you have a problem with climate control (humidity of 45-55%, and a temperature of 65-75oF), humidicant packets can be useful. Check out the curing problems page for more information.
While the buds are curing, open the jar and check for moisture. Empty the jar out and check for rogue moist buds. If they are cold or moist, lay them out flat on parchment paper with air circulating. It could take a few hours, to overnight for them to dry enough to be placed back into the jar. That is not usually necessary if the flowers have dried enough. After about 14 days, they should be ready to smoke.