Water brings life to animals and plants alike and without clean oxygenated water, cannabis plants and plants in general can and will not survive.
When choosing a water source for your garden it’s important to take into consideration what is IN your water and how it might effect your garden, for instance maybe you live in Oakland, California and you’re using EBMUD water straight from tap without any advanced filtration (Reverse Osmosis etc), this water will (depending on time of year) be very mineral rich (mostly calcium) and is considered hard water, which in turn will have a higher PH of around 8.0 and if given directly to plants it might cause stress because cannabis plants crave a soil environment that is around 6.5- 6.8, for this reason it is important that every cultivator owns at least one PH meter and at least one PPM or TDS meter so that they can check their source water, be it from a stream or from tap to ensure that the PH and the Total Dissolved Solids remain in a healthy range, and if your water is not optimal you can always adjust PH with PH up and down solutions (alkaline and acidic solutions) and lower TDS by way of multi stage filtration.
[never use a water softener when growing cannabis! Softeners commonly use salt which can build up on your roots and kill your crop!]
When using water directly from your tap it is important to check the PH and as to make sure not to use water that is exceeding 1200PPM and to check that the PH is around 6.0-7.8, we recommend checking your local water supply PDF that should be available on your cities municipal website.
Adding nutrient solutions to any water will effect the PH and PPM vastly depending on the initial water solution.
Active charcoal carbon filters effective at removing chlorine, sediment, volatile organic compounds (VOCs), taste and odor from water. They are not effective at removing minerals, salts, and dissolved inorganic compounds which means they should only be used as pre-filter and are often part of muli-stage RO systems as described bellow.
RO (Reverse Osmosis)
RO filtration is slow and in some cases wasteful but will bring your total dissolved solids down to around 0 allowing a clean slate to add just the minerals that your plants desire and adjust the PH accordingly.
RO works by forcing water through a tiny membrane that allows only pure H20 to pass and holds back any minerals or impurity’s, the mineral rich waste water is then put directly down the drain or into a holding tank for other uses at a rate of about 1 gallon pure water for every 1 gallon of waste water.
(When using RO it is important to supplement with 1-5ml Calcium/Magnesium solution at every watering because without these two important micro nutrients your garden will suffer.)
Irrigation: Larger plants will always use more water than small plants but size is not the only factor that dictates a plants water consumption. The age of the plant, the size of the container and soil quality all come into play! Irrigate soil and soil-less mixes when it feels dry one-half inch bellow the soil. Check this by gently pushing your finger into the soil feeling for moisture. As long as the mix has good drainage it is very difficult to over-water rapidly growing cannabis but not impossible.
(NEVER water larger plants every day! If a smaller plant needs water each and every day its time to transplant!)
Overwatering: This is a very common issue for newbie cultivators, the result in which literally drowns the roots and starves them of much needed oxygen.
Underwatering: Underwatering is usually less of an issue but if you are growing in smaller containers you need to frequently check the moisture level using either your finger or a store bought soil meter.