Instructional Video's Coming Soon

Hello,
  I have not written any posts because I am working on some instructional video's for HTGSupply.com.  I hope to start putting video's up in March.  I am always available for E-mailed questions and comments at Askthedoctor@htgsupply.com

Good growing,
Dr. E.R. Myers

E-mail - Comparing HPS and LED

I just read your article on LED vs. HID. My question is side by side how much is the yield affected comparatively? When grown using 300w led vs 400 w hid in flower stage
Sent from my iPhone

Hello,
  I have not done a "side by side" experiment, but I do agree with my article comparing HPS and LED, that LED's are comparable to HID's, even in flowering.  I have used a 400 HPS and a 300 W LED in the same grow area at different times with the same plant type.  They were comparatively equal.  The plants were different, (same strain so genetics were the same)  The plants under the HPS were bigger, with longer node length which was due to both the increase in yellow, and the fact heat was a problem, the temps were in the 90's when the light was on.  Under the LED, the plants were more compact due to more blue light and also that with the LED, the grow area never got above 85F.

The plants were bigger under the HPS, but I'd say that when it was time to harvest there was not much difference between the two.  If you are using a 600 w or 1000 w you might want to use two LED's to get the same area coverage.  The LED's are more focused so when you get into the larger sizes of HPS with their reflectors, they can cover larger areas.
Good Growing,
Dr. E.R. Myers

Small Spaces and Containers – Maximizing Growth and Yield

Pot up early and often for maximum growth and yield

In a post in 2009 I  posted pictures where I compared plants in various sized containers, and put different numbers of plants in containers.  Smaller containers result in smaller plants and smaller yields.   Multiple plants in containers lead to smaller plants and smaller yields too.  The trick is getting the smallest sized container that will allow your plants their maximum growth in the space you have indoors.  A rule I have read is one gallon of soil/medium for each foot of plant height.  This of course depends on the species of plant you are growing, but is a good rule of thumb. 

I have noticed another problem with small containers.  Many growers start several plants in small containers and then put them up into bigger containers as they grow.  This is a good way to pick the best plants too, especially if you are doing any plant breeding.  Remember; if you breed plants don’t get mired in mediocrity.   If you keep a plant in a small container, and it gets root bound, even when you pot up the plant it will not grow to its fullest potential.
The take away message, always keep your plants roots growing.  Once the roots start to twist around and around in a container, they send out hormones to the plant that resources are going to be limited, and growth should slow.  When you pot up the plants, they will grow more, however not as much or as big as plants that were never root bound.
You should pot up your plants as early as possible.  Here is what I noticed this semester; I had two groups of plants.  Group one, I potted up as soon as roots got to the bottom of the container.  I started with small containers, then went up to one gallon then three gallon containers when I put them onto flowering.   The second group, I kept in small containers for an extra two weeks, then put them in one gallon containers for two weeks longer than the first group.  My idea was that I could get two flowering cycles in one semester.  What I noticed is that the first group plants were all tall and bushy and the second group plants were shorter and single stemmed.  It seems that when a plants roots are not allowed to grow, the hormones that slow growth somehow prevent the plant from ever reaching its full potential.  I think this would be like if a child does not get all its nutrition, it will never be able to reach its full potential, even if has all its nutrition met as an adult.

Pot up early and often for maximum growth and yield

Good Growing,
Dr. E.R. Myers

Read my post on suggested container sizes for plants

Upgradeing Lights in the Mother Keep Grow Tent

Hi doc, looking to change out my lighting setup to something new.
I'm running t5 four bulbs 4 feet long which came with the motherkeepergrow tent from htgsupply.com.
I veg/flower in the same tent, but would like a stronger light for flowering only and not sure what to use. I’m sure 1000 watt lights would burn my  tent.
Just looking for ideas I have five plants only.  Thank u

Hello,
  You could get a 1000 Watt with ductwork andventilation, they have lights where the bulb is encased in glass connected to the duct work, and plants can grow almost right up to the bulb.  But, if you switch to an HPS, you may run out of room because your plants will probably get taller than they did under the T5.  So, if I were you, I'd get an LED.   You may want to get two 135 W LED's and put them in the grow tent about 2-3 feet apart.  I love the T-5's and use them to start my plants, but your plants will really flower better under an LED.  Get a 7 band, not a single color LED.  I think you'd be better with two smaller LED's than one big one, unless you wanted to also get a light mover but that might take away from some of your space.
I hope this helps.
Good growing
Dr. E.R. Myers