Dialing-in The Other Key Factors For A Perfect Plant Environment: Light, Air & Water
As you wait for your seedling to sprout above the surface bed of medium in your growing pot over the next couple of days, prepare the other factors of your grow tent or room environment. As your plant grows, it will change these environmental factors and you can be ready for the adjustments you’ll need to make in the very near future!
Grow tents come with their own reflective walls. But if you want to convert a room for your growing area, you’ll need to hang some before adding your light and ventilation system.
Seedlings don’t need high-intensity light, so make sure your LED light fixture is right up to the ceiling of your growing area. Over the first couple of days while your seed grows up and out of the growing medium with your light and ventilation system running 24/7, you will have already created the optimum environment inside your grow area for your baby plant’s first few days!
It is a very exciting moment on the day you first discover your seed sprout has emerged out of the growing medium to become a seedling with two tiny green leaves! You’ll notice its baby stalk has already started to green up from the light energy you’ve had waiting for it. Light energy provides the life-giving process of photosynthesis. Photosynthesis powers your plant to absorb carbon dioxide from the grow area air and oxygen from its roots with the trace nutrients and sugars in the peat/vermiculite mix to supply its own energy for growth.
You won’t need to add any nutrients to your water until your baby plant has grown its first three sets of leaves. Just gently add 1 to 3 ounces of pH-adjusted aged water a day around the baby stalk and let your new light do all the growing work. Make sure that your clear water for the seedlings is pH-adjusted to the ideal range of, 5.5-6.5.
After your plant has grown its first 3 sets of leaves, you can gradually lower your light by about one foot a day. Any faster, and your light will burn your baby plant. After a few more days of lowering your light, you’ll see your plant quickly starting to grow. After the top of your plant is 3 feet from the bottom of your light, maintain this distance as your plant grows. By the time (in no time at all) your plant is about a foot high you can lower the light a little more until it is 28 inches above the top of your plant.
At this point it’s time to change your light cycle on your timer from being on 24/7 to being ON 18 hours and OFF 6 hours for a full 24 hour light cycle. Visit to feed your plant and tend to your indoor garden in the mornings of its new day time light schedule—which is any time that works best for you! Do not disturb it during off time and give your plant a chance to rest, rejuvenate and relax so make sure it has TOTAL darkness for that 6 hours and keep your door closed and sealed off from all light.
After your plant is 8 weeks old or 2-3ft. Tall, its time to change your light into “Flowering” cycle by adjusting your timer to 12 hours ON and 12 hours OFF for TOTAL DARKNESS. Even though it is only getting 12 hours of light at this point, your plant will amaze you by continuing to stretch and grow!
NEVER allow light “leaks” to disturb your plant’s 12 hours OFF for TOTAL DARKNESS. Constant disturbances of light penetrating into the 12 hour dark period will either prevent your plant from flowering or shock it into a state of “hermaphroditism” where it will produce both male and female flowers. These will “self-pollinate” your plant causing it to produce inferior hermaphrodite seeds and inferior female Bud potency because YOU will have let your plant go to seed!
In another Blog post we’ll show how to determine the sex of your plant in the early weeks of flowering. You’ll want your new plant to be female because UN-pollinated female flower Buds use all their energy to create the high-potency THC and CBD’s we love instead of using their nutrients and energy to produce healthy seeds.
Carefully watch everyday for signs of burning. Signs of burning are the baby leaves turning yellow around the tips and edges. Burning signs mean your plant is not ready for that much light intensity, so pull up your light a few inches each day until you can see your plant is growing happily “green” out of the,“light intensity stress zone”.
If no signs of light stress occur after you’ve lowered your light to a distance of 28 inches above the top leaves of your plant (known as the “Canopy”) and it continues to grow vigorously, you’re all set! Just keep that distance of 28” right into the first several weeks of flowering.
We’ve let you see into the future of your new indoor garden, now let’s return the beginning: even after your plant isn’t even a full foot tall yet, it will dramatically change the growing environment inside your Grow Tent. And the major environmental factor it will change is the air…
Photosynthesis in an amazing process! As photosynthesis drives your plant’s growth, your plant will “drink” more and more water. Many folks don’t realize that only 5% of all the water a plant drinks in a day is actually used nutritionally. The other 95% of the water your plant will drink in a day is expelled right back out again through its leaves with oxygen as a waste gas, into the ambient air of your garden through a process called, “Transpiration”!
Without correctly managing the ventilation system you initially set up in your growing area, the air inside will build dramatically both in humidity and heat.
When the humidity and heat levels become too high, growth comes to a stand still. If allowed to continue, high humidity and heat will suffocate your plant by bringing both photosynthesis AND transpiration to a halt. And if, for some bizarre reason you allow the air temperature to fall and the humidity in the air to dry out completely, low heat levels will also stop both photosynthesis and transpiration. If allowed to continue, your plant will die. This last scenario rarely occurs, so what growers need to control most is heat and humidity levels. You can read more about transpiration and photosynthesis in our other blog post by clicking here.
Luckily, controlling heat and humidity levels inside your new grow area is not as precarious as it sounds. All you need to do is keep your silent-running ventilation system running throughout the entire life of your plant. If you find you need more control, in an up-coming post we will show you how to add a thermostat control box that will turn your ventilation off and on to maintain the perfect temp and humidity.
Cannabis plants love a little more heat and humidity than people do. The ideal ambient air temperature inside a cannabis grow operation is between 75 and 80°F (24 and 27°C). The ideal relative humidity level to maintain for your cannabis plant in the vegetative cycle is between 40 and 60%.
When you mount your exhaust fan on an upper wall or ceiling port, the fan will pull the rising heat created from your grow light out of the growing area while at the same time drawing the fresh air of the tent’s outer room (or grow room’s next door neighbour room) IN through an open intake port. This is great air ventilation, and your plant will love you for it!
When you visit your plant daily, take advantage of the Control Unit you’ve hung on the inside wall of your new growing area. This handy digital device will show you the temperature, relative humidity level and time of day with a thermometer, hygrometer and a clock respectively. During your plant’s “day time”, the Control Unit will show you the exact temperature and humidity level inside your tent. If they are a little too high, you need only turn down the heat in the growing area. As for summertime: if your residence does not have central air, then you can get a little “portable” air conditioner just for that growing area.
Never, NEVER exhaust the air from your growing area into another room and especially into a basement or an attic if you have one. Forcing your exhaust air into another room, an attic or basement will damage your residence with mold. Mold can be VERY expensive or even impossible to get rid of!
Forcing your exhaust air into another room will only increase the temperature and humidity inside of your living area which ultimately recirculates BACK INTO YOUR GROWING AREA!
(Stay tuned: we’ll be zooming in on the details so you can do this easily and successfully no matter where you live!)
So take advantage of some duct line and vent your growing air out of your growing area and completely OUT of your residence. Doing so will give your plant a healthy stable growing environment at the ideal temperature and humidity it will thrive in! This simple perfection will ultimately produce the bountiful, potent Buds you’re looking for! All you need to add after that, is the love…AND the water!
When it comes to “watering” cannabis, what experienced growers refer to is actually not only the pure fresh water, but the nutrients included in it!
Let’s begin with the water itself first.
What exactly is, “pure fresh water”? If you live in a small town or big city, the closet thing to fresh water you’ll find is rain, or melted snow water. But with heavy concentrations of air pollution the rain or snow absorbs on its way down, “acid rain” isn’t pure. If you live far from urban centres in a quiet rural area, rain or snow water is great. It isn’t exactly the most convenient source of water, however. So no matter where you live, if your tap water is certified “potable” and safe to drink, it will work fine with your plants.
You can easily remove the toxic chemicals like chlorine from your tap water by preparing a mini-reservoir in a 10-50 gallon food-grade bucket or “barrel”. Fill it up with tap water and let it stand uncovered for 48hrs., and all the toxic “water purification” chemicals will evaporate out of it.
There is one thing however, that will not evaporate out of your water: pH
The symbol of “pH” is actually a figure expressing the acidity or alkalinity of a solution (i.e. water and your plant nutrients) on a logarithmic scale in which 7 is neutral; lower values are more acid, and higher values more alkaline.
Most cities and towns jack up the alkaline in their tap water to prevent plumbing from rotting out. Therefore, you’ll have to get a pH test kit. Test your water for pH levels after you’ve added your nutrients to your water. Most test kits come with a small bottle of pH UP and pH DOWN.
The ideal pH for most cannabis plant’s water-nutrient solution is between 5.5 and 6.5. So, after testing your nutrient solution, if it is too high or too low, adjust it appropriately with a few drops of either pH UP or pH DOWN.
Just make sure you keep your main water reservoir outside of your grow area. Even if you cover your stored water after 48hrs, your grow light is powerful enough to generate Algae growth. Not only will Algae itself choke your plant roots, but it will use up all the oxygen your cannabis roots need.
More importantly, your main water reservoir should be kept out of your growing area to keep it cooler than the ambient air temperature inside your grow area. Remember, the optimum air temperature inside your grow tent, should be 75-80°F. Plants efficiently utilize water when it is roughly 5-10 degrees cooler than the ambient air temperature in their growing environment.
When water stands too long however, the life-giving oxygen in it, evaporates as well!
What’s a grower to do?
The answer is simple. Aerate your plant water!
This can be accomplished easily two different ways. The “automated” method is to buy an aquarium air stone, some air line and an air pump. Attach the air stone to enough air line that the air stone will be submerged and under the water on the bottom of your reservoir and attach the other end of the air line to air outlet on your air pump. Plug in your air pump, keep it running 24/7 and you will have a steady supply of fresh oxygenated water.
An even simpler and FREE way to aerate your water is to “hand bomb” it directly before you water your plant from your water/nutrient solution you keep inside your grow area in a small 5 gallon reservoir. With a clean can or large mug, scoop the solution up and pour it back in your water/nutrient bucket 3-5 times, and like a water fall, your water will be aerated!
When you keep a 5 gallon bucket of pre-mixed nutrient solution (adjusted to the correct pH level) inside your grow area between the bottom wall fresh air intake port and fan, and the drain pan, your ventilation system will automatically keep your nutrient solution 5-10 degrees cooler than the plant’s ambient air temperature inside the grow area! It will accomplish this the same way as your vent system removes the hot humid air out of your grow area: as your vent fan pulls hot air away from your grow light and out of the grow area, it will simultaneously pull fresh air into your tent through the intake port and fan. This continuous action will bathe your nutrient bucket with cool fresh air and keep it much cooler than the air your plants are breathing!
Most pre-mixed plant nutrients are formulated to be added to water meant for watering your plants, so the watering and fertilization process can be done at the same time. Your friendly neighbourhood grow shop stocks premium organic liquid plant nutrients (fertilizer) designed for explosive plant growth and flowering development so all you need to do is follow the instructions on the nutrient bottle to mix the correct proportion ratio of nutrients to your water so that after mixing, all you need to do is adjust the pH in the “water”!
Don’t worry about the pH level changing daily while you go through the 5 gallon bucket of your nutrient solution inside your grow area.
And if you don’t prefer the “hand-bombing” method to aerate your plant nutrient solution, just keep an air stone bubbling in the 5 gallon bucket inside your grow area. If you keep the air pump outside of your grow area, which will be cooler, your air bubbles with help keep your nutrient solution cooler too! Then, just sit back and watch your plant grow like gang busters!
But this leads us to the all-important question that professional growers are constantly debating: How often and how much should I water my plant?
You don’t need complicated numbers and formulas to answer this question. All you need is your 5 senses, particularly your sense of touch and your sense of sight. And this is why we originally recommended you start simple with a peat moss/vermiculite mixture growing medium: it’s high-drainage properties make it virtually impossible to over-water—a “killer” crime most new growers are notorious for committing.
Once your seedling has grown 3 sets of baby leaves you can begin adding nutrients to your water.
Your preferred nutrient company will give you the correct ratios to mix right on the bottle. You’ve pre-moistened your whole plant pot of medium even before planting your seed, so…
Now, all you need to do is water daily just a little bit at a time. Again, your nutrient company will specify how much. As your plant grows it will require more and more water/nutrients each day. An ounce a day to begin and quickly you will see your new plant “green up” to beautiful shades of emerald as it gets taller and bushier by the day!
Just remember, cannabis loves airier “drier” soil in a natural setting. In your artificial indoor grow area environment however, “drier” doesn’t mean “bone-dry”. Just stick your finger in your medium on each daily visit to your plant. If the medium feels moist and not wet, just water appropriately a little every day. As your plant grows, it will need relatively huge amounts of water just to keep the medium moist when its 6 feet tall compared to when it was just a baby at 3 inches.
You will find that growing your own Cannabis in your new growing area is truly a miraculous adventure where you can experience the relaxing and rejuvenating feeling of becoming at one with the world and Mother Nature right in your own home!
So take heart in your exciting new learning experience, for learning involves making mistakes and many questions along the way. We hope this post has helped you avoid the problem so many new growers make by “painting themselves into a corner” by germinating their seeds without first having a growing area to plant the seedlings in!