THC - Times Have Changed, So GROW with them



COMPANION PLANTING - Why not try with Cannabis …?


How do different factors affect the rate of photosynthesis and transpiration in plants?

Effects of light intensity and air velocity on air temperature, water vapor pressure, and CO2 concentration inside a plant canopy under an artificial lighting condition.


Red Light and Plant Growth


Detect Powdery Mildew Early

English marigolds (Calendula) are quick to get powdery mildew so we use them as an indicator plant.

Marigolds are one of the easiest plants to grow hydroponically, they prosper in a hydroponic setup. Starter plugs are the best way to get growing, but other media will suffice.

Although the seed itself naturally contains all the nutrients it will need to start life. Pre-treating the hydroponic media with a 1/4 strength nutrient solution is helpful as the seeds germinate.

Air temperature should be in the ballpark of 60-70 F day cycle and 45-55 F night cycle. Solution temperature should be within a few degrees of 70 F. See: Hydroponic Temperatures. Marigolds will not tolerate cold.



This concept is going to sound backwards to many, but years of cannabis growing experience have shown that the best way to produce the highest quality product is to cull plants at each stage of growth.

Professional gardeners know this rule well, but most cannabis growers do not. In fact, it seems backwards to many cannabis gardeners to throw out parts of plants as they are transitioned through the different stages of the plants life-cycle (i.e. clone/seedling, vegetative, flowering) as they have put effort in keeping these plants alive and as healthy as possible. However, culling plants at each stage will produce a more robust and higher yielding crop through the selection of the strongest individuals and the discarding of weak sections of plants.


As plants grow, their true character comes out. Plant growth characteristics can be delineated as: sensitive to low, medium or high amounts of dissolved solids in water, preference for direct or indirect light, susceptibility or resistance to disease and pests, short or long internode length, etc. Some are large growers, some are not. Some are prone to bugs and infections while others are more hearty. Some can thrive on limited nutrients and others need to be pampered to reach their full potential.

These differences cannot be seen simply by looking at a seed or clone cutting. Instead, they only show up once the plants have a chance to grow and are exposed to your individual growing style and cultivation environment. As such, it is recommended to cull plants at each stage, before moving them into the next phase. This means that you survey your tops, select the best ones to move on and destroy the rest or use as clones.

Let’s repeat that, at each stage of the grow, throw some leaf/tops away and keep only the best performers.

In order to make this work, culling losses must be factored in from the beginning. For example, let’s take a conservative estimate of 10% culling loss at three stages; clones, rooted clones, and vegetative growth. strong text This culling loss can (and should!) be adjusted based on your success rate and cultivation style. When losses are not factored in from the start the pressure to produce often overrides plant quality. Gaps in your healthy plant count are filled with less than desirable replacements which in turn brings yield potential down and increases the potential for pest/disease incursion, both of which create more work for facility personnel.


By doing this, the tops that make it through to harvest will be the best performers. You won’t be struggling with underperforming plants or playing “catch-up”. The culling process can help avoid many common cultivation setbacks associated with pests, disease, and genetic drift, since sickly plants are often the most vulnerable. The plants selected in this process will produce higher yields and better looking products. You will easily be able to make up the cost of starting extra plants through the quality of the ones that make it to flowering.


Consider Essential Oils for Your Garden

ILGM CherryPie - Seed to Harvest, First Grow Journal
Help...fungus gnats

How to Deal with Humidity in the Growroom

New guy about to take the plunge