cycles for indoor growers are 18 ON / 6 OFF for vegetative growth and 12 ON / 12 OFF for flowering .
Questions to ask : Are the leaves and budsites of my plant receiving light necessary for photosynthesis ? What spectrum of light is my plant receiving ? Is that ideal for its current stage of growth ? How many uninterrupted hours of darkness is my plant receiving each day ? Is that appropriate for the intended stage of growth ?
Temperature and Humidity
Fundamental concept : Cannabis grows best in temperatures between 70 to 85 degrees Fahrenheit and humidity levels between 40 % and 75 %. If the temperature is held constant , plants prefer humidity towards the higher end of the range during vegetative growth and towards the lower end during flowering . Low temperatures with high humidity are breeding grounds for pests and pathogens , while high temperatures with low humidity limit the plants ’ ability to grow .
Questions to ask : Are temperature and humidity at or near the optimal range ?
Air Exchange
Fundamental concept : To perform photosynthesis , cannabis absorbs carbon dioxide ( CO2 ) present in the surrounding air . As CO2 in a room or tent becomes depleted and replaced by oxygen emitted from leaves , it must be replaced at least every three minutes .
Questions to ask : How frequently is CO2-depleted air being extracted from the grow area and replaced with fresh , CO2-rich air ?
Water
Fundamental concept : Cannabis grows best when provided clean water in a particular pH range that allows the full range of necessary nutrients to be absorbed by the plant . For soil , that pH range is typically 6.0 to 7.0 . In hydroponics , it ’ s 5.5 to 6.5 .
Questions to ask : Is my water free of harmful microbes ( i . e ., bacteria and fungi )? Is the pH within the optimal range for my particular grow methodology ?
Nutrients
Fundamental concept : Cannabis requires a mix of primary and secondary nutrients to grow properly . As a seedling , it needs almost no external nutrition because all the energy it needs to sprout and develop a root system is stored within the seed itself . Once roots have been established , a vegetative state of growth begins with heavy needs for Nitrogen and Potassium and about half that level of need for Phosphorous . During the flowering stage , cannabis requires very little Nitrogen but has heavy needs for Potassium and Phosphorous . Throughout both the vegetative and flowering stages , it will require small quantities of secondary nutrients , the most in-demand being calcium , magnesium , and sulfur . Manganese , boron , sulfur , iron , molybdenum , zinc , and copper are also necessary , but in much smaller concentrations . It ’ s not just a matter of making all these nutrients available ; it ’ s also important to keep them in balance . When one or multiple nutrients are far outside the proper ratio , they can impact a plant ’ s ability to absorb the others . For instance , overfeeding calcium and magnesium to cannabis can result in a potassium deficiency .
Questions to ask : What nutrients are available to my plant ’ s roots ? Are those nutrients appropriate for its current stage of life ? Are the concentrations of those nutrients balanced to what the plant requires ?
Oxygen
Fundamental concept : Roots require access to oxygen , just as they do any other primary nutrient . Starve them of oxygen , and they ’ ll quickly rot and die . Soil or grow media must be somewhat light and loose enough for oxygen to make its way to the roots . If it becomes waterlogged for a significant time , roots will suffocate . Similarly , roots suspended in water ( as with a Deep Water Culture hydroponic setup ) can benefit from an air pump and air stone combination , forcing fresh O2 into the standing water .
Questions to ask : Is oxygen reaching my plant ’ s roots ? Is my soil allowed to dry enough between waterings to prevent root rot ? Is there sufficient fresh oxygen being introduced to the water or nutrient solution in my hydroponic setup ?
Hopefully , these fundamental principles and questions will act as gentle reminders to keep your grow on track , no matter how deep down a rabbit hole you may have descended . If you ’ re a first-time grower , asking these questions will help ensure that your first garden is heading down the right path .
For more information about YRG , visit
www . year-roundgarden . com or call 816.216.6917 and be sure to tell them The EVOLUTION Magazine sent you .
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