E-mail. Best Light for Seedlings

I got an E-mail asking what the best light for growing 'greens' is, meaning growing plants for leaves.
They asked if they needed any special color of light like red or blue.

All plants need BOTH red and blue light ALL the time.  However, blue light promotes vegetative growth, so a light like a T-5 is ideal.  Red light promotes flowering, but is also needed for day to day physiology maintenance in plants.  A T-5 will also have some red, enough for seedlings.  If you are going to flower plants, you will want a lite like an HPS, or an LED.  All the LED's from HTGSupply.com will have enough blue and red for both vegetative growth and flowering.

E-mail me with any questions,
Good growing.

Video - Easy Way to Measure Seedling Health

Please click here to watch my short video about how I measure seedling health
Good Growing,
Dr. E.R. Myers

Cleaning Mold of Walls of Grow Room

Click here to watch a YouTube video about removing mold from  your grow room, and general cleaning advice 

Good Growing,
Dr. E.R. Myers

Seed Germination Video

Please click here to watch a video on YouTube about seed germination.

Good Growing,
Dr. E.R. Myers

Day Light Savings and Your Light Cycle

If you had your lights go on or off based on your work or life schedule, the best thing to do to get the light back on your schedule after day light savings is to shorten the light cycle (turn lights off early).  You can shorten the night cycle (turn lights on early) it won't be too stressful to your plants to cause harm.  The reason I suggest shortening the day schedule is that will help speed up flowering if it does anything to the flowering cycle.

Good growing,
Dr. E. R. Myers

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

Pruning Plant Tops - Plant Hormones and Plant Growth Patterns.

If you read my post on how plants grow, you know that most plants (other than grasses) grow from the top, (specifically in an area called the apical meristem) and I mentioned in this post  some ways this knowledge can help you be a good grower.  There are other ways this knowledge can help with plant growth.  The apical meristem (link to plant growth article) is also where many hormones are created/secreted.  If you cut  off the top of a plant, most of you know the plant will get bushier.  I often do not recommend doing this*, as it stresses the plant to have its apical meristem removed.  Cutting plant tops can be necessary with some growth methods (read my post on the sea of green technique). 

The physiological reason why plants get bushier when the top is cut off or bent is that one of the hormones that will be no longer made by cutting the top of the plant used to prevent the branches from growing, this is termed apical dominance.  Without the plant top, the branches will be grow at an increased rate from their meristem tissue, termed secondary meristems.  This means each branch will elongate, and each branch will secrete more hormones.  In some plants, one of the branches will become ‘dominant’ and suppress growth of the rest of the plants, making the plant start to grow tall again.  Other plants will just become bushy and will have lessgrowth in height.

Good growing,
Dr. E.R. Myers

* I more often recommend bending the top of the plant, this will slow the hormones, and make the plant more bushy (less tall) without the stress of recovering from cutting off the top.  The benefit is that bending  does not result in several days where the plants do not grow because the apical meristem was lost and the growth hormones, are gone.

 

The Down Side of LED’s

If you have read my blog from the beginning, you know I’ve gone from thinking the best light is an HPS, to using LED’s and loving them.  The intensity of the tri-band and seven-band LED’s from HTGSupply.com have proven to be awesome at growing plants indoors.
No one light is going to be the best for everyone everywhere.  A friend of mine has a detached garage, and I helped him put in a 10x10 grow room in the garage.  The garage gets hot in the summer, and he is thinking about putting in an A/C unit.  I suggested he just grow outdoors in the summer and save electricity.   I also suggested when he wanted to try something different he use LED’s instead of the 1000 W HPS he had.  The plants are growing great.  However, what he’s noticed as the weather gets colder is that the often unwanted heat of the HPS was needed in the grow room.  The HPS was run at night, and keept the grow room in the 60’s on cold nights.  This week he noticed that the room was getting down into the 40’s when it was in the teens.  40’s won’t kill plants, but it can stress them out, and will really slow down growth.  Worst of all, winter is just getting started.  So, if you are in a situation where the heat from an HID is necessary to keep the room warm in the winter, then you may not want to switch to an LED.
Good growing,
Dr. E.R. Myers

Did Day Light Savings Change Your Prefered Light Cycle?

If daylight savings changed your light cycle, and you want to change it back, it is better to have a longer night than a longer day if your plants are flowering.

Click here to read my post on how best to switch your plants after daylight savings

Good Growing,
Dr. E.R. Myers

Drying Herbs

In my post in 2009 about drying herbs I mentioned you could quickly dry herbs with fans, and in fact air movement is important to prevent mold, but that slow drying often brings out the full flavor.  I want to expand on this, due to an E-mail I got from a reader.  He suggested that the slower the herbs dry, the better for the flavor.  He recommended putting the herbs in a Tupperware container after 2-3 days with the lid on but NOT sealed.  Open the lid in a couple hours, if the herbs seem wetter, keep the lid off.  After a day or two, put the Tupperware lid on tight on one corner (always make sure the herbs feel dry when doing this, if they feel wet, you will have mold).  Open the lid a couple times a day and feel the herbs.  When they are completely dry (I keep a stem in with them and when it snaps easily, and does not bend, the herbs are dry) seal the lid and store the herbs
Read my post on Herb Storage
 I concur with this slow drying.  In fact, even though plants are technically dead when you cut them, there are physiological reactions for many hours, and chemical reactions for days.  Once the water content becomes very low, most chemical reactions and all biological ones will stop.  By slow drying, you allow for the molecules in the plant cells to interact completely.  Now, the fun thing for me about biology is that there are always exceptions.  So, some plants you might want to dry quicker than others.  The best way to test this is with a scientific experiment.  Have two or more types of drying techniques with not just the same herb, but the same plant.  
Good Growing,
Dr. E.R. Myers

Create an Environment For Fast Germination and Maximum Seedling Growth.

Now that fall is upon us, and for most of us the outdoor growing season is done, or will be done soon, it is time to concentrate on our indoor garden.   I always encourage my readers, and students to try new things in a scientific manner.  This can be done if you are growing multiple plants in multiple containers, simply treat a group of pots one way, and compare them to the group(s) that you treated differently.  Hydroponic systems that share a reservoir do not lend themselves to this type of experiment.  However, with careful notes and measurements, you could compare one growing season to another where you tried something new.

With seed germination, you want to create a warm, moist environment.  I’ve hear many a gardener say to put germinating seeds on top of the refrigerator because this is a warm spot in the house.  That is free, and ok, but the AgroMax Heat Mats sold by HTGSupply.com are perfect for increasing germination.  You do not want hot, that can actually kill your tender young seedlings, so never use an electric heating pad, or put the seedlings in an area above 90F.  The heat mat heat raises the temperature a few degrees above room temperature.  You can use any medium for your seedlings, but as I’ve said, I really like the starter plugs.  You can also put seeds on a moist paper towel in a baggie and put the baggie on the heat mat
    With the heat mat, you should see seed germination in a few days.  If you are using the starter plugs, or if you put your seeds in soil etc. to germinate them, you have a week or two before you need to do anything.   I would keep the light on 24/7 for the first few weeks to maximize growth.  After a month, I switch to 18 on 6 off until I induce flowering.  If you are doing your germination on a paper towel you need to get the plant into the medium asap as soon as you see the root coming out of the seed.  There are no nutrients on the paper towel, and I have found you get mold if you do use fertilizers on the paper towel.  Moreover, the small roots are delicate, and if you break off the root tip when you plant your seedling, you just killed you plant, or at best set it back a week or two in growth.   You will want to keep the light a bit higher (1 foot or so) for seedlings than mature or flowering plants.  Too much light can stress out a young tender seedling.  After a week, you should see growth and you can lower the light and start to use fertilizer (I usually recommend ½ strength for the first 1-2 watering’s.)  You are well on your way to a successful growing season indoors…

Good Growing,

 Dr. E.R. Myers

 

Click here to see my test for the best medium for seedling germination.

How to Tell if Your Plants Are Growing at Their Maximum

Look at your plants.  Do you notice that the top leaves are small and seem not to be growing?   The plant can look healthy, but are the leaves on the branches growing?  For most fast growing plants grown indoors under a light from HTGSupply.com, you should see changes in growth every day.  If your plant seems to be stuck, your plant may be root bound. (click here to see pictures of a test I ran on pot size)
Even if you do not notice slowed growth, good growers know that when you harvest your plant, you should take a look at the roots.  If you see a white ball of roots and no soil at the bottom, or the roots are in the shape of your container try a bigger container next time.  When plants roots get compressed in a small pot, the plant will grow smaller and have less yields, as well as be more susceptible to fungal infestation and other diseases.
Good Growing,
Dr. E.R. Myers

What to do Between Vegetative Growth and Flowering

Good growers know that when plants are in different phases of their life cycle (seedlings, vegetative growth and flowering) they have different nutrient requirements. 
Read my post on how to improve flowering
If you just read the above post, you know you want to reduce nitrogen, but not eliminate it when your plants are in flowering phase.  All living things need nitrogen, and plants are no acceptation.  Many fertilizers labeled “For Improved Flowering” have no nitrogen, and I think this is a mistake.  Nitrogen is used by plants in all phases of the life cycle.  While nitrogen promotes vegetative growth in large quantities eliminating it will slow growth, and lower yields.  Everything in Biology follows the Goldilocks principle, not too much, not too little, just the right amount.  When my plants are flowering, I use a fertilizer that has a low number for nitrogen, like Big Swellwhich is 2-5-7.    
If plants are green, healthy looking and over all doing well when you alter lights for flowering) just use something like Big Swell2-5-7.  If you have brown leaf tips, stretching nodes, and reduced root growth you may have a lot of nitrogen and you should use something like Big Bud which contains no nitrogen after the plants dry out from  thoroughly  being watered with pure water.  After this, I'd go with a now nitrogen fertilizer for the rest of the flowering cycle.  Hydroponics like soil growers should always provide some nitrogen to their plants.  It is normal that yellowing should start to occur in flowering, this is a sign the plants are focusing on flowering, not making new leaves.  Be sure to give the plant a bit of nitrogen to keep it growing well through the flowering phase, which for most of us, is the most important part of plant growth.
Good Growing,
Dr. E.R. Myers

Fungus in the Grow Room

I get a few E-mail’s about fungal problems.   Many times I am not sure if it is fungus, or a phosphorus deficiency.  The leaves at the bottom would get brown/grey and dry and shrivel up.  I usually ask about phosphorus, but most people use too much nutrients, not too little.  I then recommend adding some lime to the water to adjust the pH, thinking maybe if the soil pH was too high, the phosphorus would not be absorbed.  It seemed the plants would limp along and people would eke out a small harvest.  I know most people would be happy to get anything when it looked like the plants were going to die, but after a second and third time, it is time to get this problem under control.

Air flow and lowering the humidity are too very important ways to reduce fungus.  Another very important factor is making sure the plants are growing in good soil, I like to add perlite or sand to most mixes I buy.  This allows the roots to grow.  Healthy growing roots send a message to the top of the plant to keep growing, nutrients and water are on the way.  If your plants are root bound, they will be more susceptible to disease and fungus. (read my post on potting up) If those environmental measures don’t keep the fungus away, you can try using Serenade.  I have used it and it works. 

Click here to read about fungus and cuttings

Click here to read more about fungal prevention

Please E-mail me with any questions or comments

Dr. E.R. Myers

E-mail - Is a LED the Right Light?

I am in need of a grow light.  I had bought a 90W 3 band ufo on another site claiming to out preform a 400W HID and cover a 4x4 area, but after several months I am very unimpressed.  HTG recently recommended the 430W 7 band LED as being able to cover a 4x3 area.  This seems to mean to cover the same size area I could either run a 400W MH (which I already have a ballast) or the 430W LED.  I switched to LED in the first place because my utility provider is very expensive compared to others around.  Currently what do you believe would be the best option?  In several of your old posts you recommended the tri band LEDs, but why not the 7 band?  I will need to ventilate either way so that is not an issue.  The HID lights are much cheaper, so what makes the LEDs so much better aside from longer life.  I want the ability to cover about a 4x4 area, but be as energy efficient as possible.  What are your thoughts?

Thanks

I agree with your thinking.  The LED, will cover that area, you can keep it 3 feet or a bit higher above the plants to cover more space.  White walls will be your best bet to increase reflection; don't forget to paint the inside of the door too.

The 7 Band 430 watt LED  uses about the same electricity, as a 400 w MH but the LED will grow plants great.  If energy conservation is a priority, you could get away with a 240 watt LED, but you might not be able to fill all your grow area. I can tell you any LED from HTGSupply.com will be better than a MH, especially if you are going to flower your plants.   With a MH or HPS, you will need to replace the bulbs every couple years, if you want to get the most from the lights.  LED's don't have this problem; they last for 80,000 or more hours with little to no loss of output.  So, the LED will save you on electricity and will give you great plant growth for years without having to spend any more money on bulbs.

I hope this helps, E-mail me with any more questions,

Good growing,

Dr. E.R. Myers

Plant Dermal Tissue – Stomata, Root Hairs and Trichomes

Plants like all complex life on earth are organisms, made up of organs.  Leaves, stems, roots and flowers and fruits are organs found in plant which are made up of tissues.  Tissues are just made up of a combination of cells working together.  The tissue types found in plants are ground tissue, dermal tissue and vascular tissue.    Ground tissue is where cells that do the basic plant metabolism are found. Vascular tissue is where cells form tubes to transport material around the plant, much like our veins, arteries and capillaries.  The dermal tissue is the outer layer of the plant.  Most plants have a waxy layer called a cuticle that protects the plant from UV damage, prevents dehydration and can help protect from predation.  Under the cuticle, in the epidermis we find some specialized cells.  Guard cells are specialized cells found in pairs.  The opening between the guard cells is called a stoma (stomata is plural).  The stomata are where plants take in CO2, and release H2O generated during photosynthesis.  Many plants have a lot of stomata under the leaf, and indoors without rain, you may find increased plant growth if you mist or apply foliar spray to the leaves to rinse the dust out of the stomata.  However, mold can also benefit from foliar sprays, if you are only growing plants indoors under a light, and they only live a few months, you might not need to clean out the stomata, but if you have plants indoors that are year’s old, maybe spring cleaning should include a shower for your plants.

Other outgrowths of the dermal tissue are trichomes and root hairs.  Root hairs occur below ground, and are very important to plants because the root hairs increase the surface area of the roots, increasing water and nutrient uptake.  Many beneficial bacteria and mycorrhiza fungi are actually smaller than root hairs, so they increase nutrient and water uptake.  Your roots should be white and‘fuzzy’ if your plants are healthy, the fuzzyness is the root hairs seeking water and nutrients for your plant. Root hairs usually only last for 2 to 3 weeks and then die off.  This means you will find healthy root hairs at the ends of your roots, which makes sense, since the plant may have used up nutrients around the old root hairs.  The take away message   is that you want to minimize damage when potting up, which is one reason I recommend using the starter plugs vs. just plain sol for seedlings.

Trichomes are a general term for outgrowths that occur on the stem and/or leaves.  I could write many posts about the different kinds of trichomes.   In many plants these little ‘hairs’ help plants regulate water and heat loss.  They can also help with predation with both small and even large herbivores.  In some plants substances are secretedseveral basic functions or advantages of having surface hairs can be listed.  Studies of trichomes on plants subjected to frost show the ‘hairs’ keep the frost away from the living surface cells.   Other studies show that dense coatings of “hairs” reflect solar radiation, protecting the more delicate tissues underneath

Good Growing,
 Dr. E.R. Myers

How to Get Cloning Success for 20 Generations and Counting…

Do you know about the first mammal ever cloned?  The sheep they names Dolly.  Dolly was just one of many attempts to clone a sheep, she was the first that survived.  It was heralded as great success.  However, many people do not know the end of the story,  Dolly had to be euthanized when she was only 6 (sheep live to 10-12 commonly)  The problem was she was suffering from geriatric diseases.  The problem with cloning is that cells keep track of your age, so if you clone a 5 year old sheep, its cells will know, and act, like they are 5 years old the day it is born.  This limits animal cloning today, since you need to wait for an animal to mature to know if it has the characteristics you want in the clones.  The same is true for plants, the cells know how old they are.

Good growers know that you can only clone a plant so many times.  Many scientific publications have shown as few as 5 times are possible to get a plant to clone without changes in growth, yield etc.   I have a friend that has cloned her plants over 20 times, and has no noticeable difference.   Here is the trick...  Plants measure days in light and dark cycle, with a substance called phytochrome, (click here to read a post about phytochrome and plant flowering)  so it would make sense that a plant that was kept on 24 hours of light might think it was one day old.  This would make a HUGE difference in cloning longevity compared to growers that use an 18/6 light cycle.   A plant on 18/6 will be a month or more old when you clone it, (it will have had 30 days and 30 nights) and if its offspring are cloned using 18/6 they will add another month to the age.  After a few generations of cloning, the plants will think it is a year old, which for annuals means they will start to show growth abnormalities and have reduced yield etc.  Compare this with a plant that was on 24/7 for a month, it might think it is only a single day old!  If the next generation are then put on a 24/0 light and then cloned, the plants would be two days old.  This could be a way to have cloning work for maybe 100’s of generations. My friend is at 20 and counting with no signs of problems.  If any readers have any input, on this topic, please let me know.

 

Good Growing,
Dr. E.R. Myers

Click here if you'd like to order clonex which will also help improve your cloning success