MarijuanaCannabis Growing Guide Part 8A Marijuana Garden At HomeTable of contents [Overview] [Genetics And The Marijuana Plant] [Germination] [Growth Stage] [Flowering Stage] [Grow Lights][Male And Female Plants] [Sinsemilla] [Growing With Hydroponics] [Soil Growing Indoors] [Shelf Growing With Soil Indoors] [Soil Growing Indoors And Outdoors] [Growing Outdoors] [Guerrilla Growing] [Harvesting] [Storage] [Security] [Odors] [Pests] [Nutrients] [Foliar Feeding] [pH] [Carbon Dioxide] [Temperature] [Venting] [Transplanting] [Pruning] [Cloning] [Breeding] Carbon DioxideElevating carbon dioxide levels will not increase the potency of marijuana but it can increase growth speed a great deal, perhaps even double it. This will allow you to harvest more often, meaning more marijuana will be produced in the same area. It seems that the plant evolved in primordial times when natural CO2 levels were many times what they are today. The plant uses CO2 for photosynthesis to create sugars it uses to build plant tissues. Elevating the CO2 level will increase the plants ability to manufacture these sugars and plant growth rate is enhanced considerably. CO2 can be a pain to manufacture safely, cheaply, and/or conveniently, and is expensive to set up if you use a CO2 tank system. CO2 is most usable for flowering, as this is when the plant is most dense and has the hardest time circulating air around its leaves. If you're strictly growing vegetatively indoors, (transferring your plants outdoors to flower), then CO2 will not be a major concern unless you have a sealed greenhouse, closet or bedroom, and wish to increase yield and decrease flowering time. CO2 can be obtained by buying or leasing cylinders from local welding supply houses. If asked, you can say you have an old mig welder at home and need to patch up the lawn mower (trailer, car, etc.) For a small closet, one tank could last 2 months, but it depends on how much is released, how often the room is vented, hours of light cycle, room leaks, enrichment levels and dispersion methods. This method may be overkill for your small closet. It is generally viewed as good to have a small constant flow of CO2 over the plants at all times the lights are on, dispersed directly over the plants during the time exhaust fans are off. Opportunities exist to conserve CO2, but this can cost money. When the light is off you don't need CO2, so during flowering, you will use half as much if you have the CO2 solenoid setup to your light timer. When the fan is on for venting air outdoors, CO2 is shut off as well. Environmentally, using bottled carbon dioxide is better because CO2 is captured as part of the manufacturing process of many materials, and then recycled. Fermenting, CO2 generators, and baking soda and vinegar methods all generate new CO2 and add to greenhouse effect. Vinegar over baking soda will work if you don't vent hot air outdoors to reduce heat. Just pour 1-2 ounces of vinegar into a container with an ounce of baking soda and close the door, (you will lose your CO2 as soon as the fan comes on if you vent heat outdoors). This method is not easy to regulate automatically, and requires daily attention but it does work in a small grow room. Even though CO2 enrichment can mean yield increases, the hassle, expense, space, danger, and time involved can make constant or near constant venting a desirable alternative to enrichment. As long as the plant has the opportunity to take in new CO2 at all times, the plants will have the required nutrients for photosynthesis. Most closets will need new CO2 coming in every two or three hours, minimum. Most cities will have high concentrations of CO2 in the air, and some growers find CO2 injection unnecessary in these circumstances. Some growers have reported to High Times that high CO2 levels in the grow room near harvest time lower potency. It may be a good idea to turn off CO2 2 weeks before harvesting. TemperatureIndoors, proper temperature for most marijuana strains is between 70-80 degrees, but using carbon dioxide will allow you to grow in temperatures as high as 85 degrees. At night, the temperature can drop 10-15 degrees without harming the plant. However, the temperature should never go very much below 60 degrees or above 90 degrees (even for short periods) or growth will slow down. If these extremes are exceeded for an extended amount of time, the plant may be permanently damaged or killed. Outdoors, low temperatures at night are ok down to about 60 degrees, then they start to effect the growth in a big way. Mid 50's will cause mild shock and 40's will kill your plants with repeated exposure. Keep your plants warm, especially the roots. Elevate pots if you think the ground is sucking the heat out of the roots. This is an issue if you have a slab or other type of cold floor. VentingVenting means using a fan to vent hot air from the growing room to another area (usually outdoors). You may have to vent with HID lamps like metal halide or high pressure sodium but less so for fluorescents. Also, humidity build up may require that you vent a few times per day. For a room with a hot lamp that builds up heat quickly, the best vent would be one that cleared the room in 5 minutes, then would stop for 25 minutes before venting again, or similarly, vent 3 minutes, shut off 12 minutes, etc. The trick is to find a timer that will do this sort of thing. Not easy to find and not cheap. Once you need to regulate CO2 on and off inversely with the fan, your looking at a climate controller. Alternatives are a thermostat that turns on a fan when a certain temperature is reached, and turns it off when the temp recedes 4 degrees. But it is hard to coordinate CO2 release with this one, since you don't know when the fan goes on. All you really want is a fan that clears the air in a few minutes, a temperature switch that turns on and off the fan, and an inverse switch that turns off and on the CO2. If you can vent the room really quick and the heat does not build up too quickly, the CO2 could be run in a slow, continuous fashion, and would build up in-between the occasional quick exhaust cycles. Two timers synced can be used, so I could have a fan run 30 mins on, then 30 mins off. I could also sync it to the light so that I don't vent when the lamp is off. I can sync this to an identical timer that will turn on CO2 during the time that the fan is not on, and vise versa. It would be difficult to sync them closer that 5-10 mins, but at least there would be a possible inexpensive solution. Fans are expensive to buy for venting, but if you can find a local electronic parts liquidators, they usually have good fans for $50-$100. A good vent fan will keep the humidity and temperature down, and distribute CO2 to your plants from new incoming air. Internal air movement is very necessary as well. An oscillating fan A good grow room needs good internal air circulation. For the first time grower, a cheap model ($20-$40) designed for home use is preferred over an expensive heavy duty industrial unit. Depending on the size of your grow room, one or more 12" to 16" units may be used. TransplantingThere will be little or no shock if you are quick and tender in your handling of the plants. Make sure you only need to transplant twice, or better yet, once if possible, through the entire growth cycle. Transplanting slows you down. It takes time, it's tricky, it's hard work, and threatens the plants. When using hydroponics, you may have to transplant once if you start growing in a cloner and later move the plant to a hydroponic garden. Or you may start the plant in the hydroponic garden as soon as the seed has germinated, in this way the plant never has to be transplanted. When growing indoors with soil, start in as large a container as possible, square is best. 16 ounce plastic cups work OK, and 2 litter soda bottles cut down may be big enough for the first harvest when growing hydroponically. One-gallon plastic milk or water containers (squarish) will work too. Or start seeds and rooted cuttings in 16oz plastic cups. It's better to have less seedlings than it is to have many seedlings that need constant transplanting. These larger cups take only a little more space, and allow you to transplant only one time before harvesting the first crop. Transplant into a gallon water jugs (cut down to 3/4 gallon) before forcing flower growth. To regenerate this plant after harvesting, transplant it into a larger pot after it goes into vegetative growth once again, 5 gallon paint buckets work pretty well if you can spare the space, and a 2-3 gallon container would make this plant's 2nd harvest better than the first, given enough vegetative regrowth first. A Russian study showed that seedlings with at least 4 inches of soil to grow the tap root were more likely to go female. The source I'm quoting says This may be why some farmers get female/male ratios as great as 80/20. © toon - updated by www.a1b2c3.com/drugs/ Books Grow Great Marijuana: |
should be used to circulate air within the grow room, to help circulate CO2. It will also keep the humidity down, allowing the air to absorb more moisture, and reduce risk of fungus.