soil basics -- LINK

I wrote an article about soil for HTGSupply.com a couple years ago.  It is located under educational pages on their website. 
If you are going to grow outdoors or if you grow indoors with soil, or mixes that contain soil, I suggest you check out my soil ariticle.

Using a soil test kit is a good idea (LINK) you can do a web search for so many more.

Good Growing,
Dr. E. R. Myers


E-mail -- LED vs HPS-2

Dr. Myers
What is the effectiveness of LED grow lights (such as the new Tri-Band type sold by HTGS) in comparison to HPS lights? Are there any reputable studies available for review showing these comparisons?
Thanks you in advance,

Your question is a hot topic right now and one I can aswer from personal experience. I will be posting pictures of plants growing under LED in the next weeks.  Until recently, I never recommended LED lights b/c there was no proof they even grew plants.  When I started to do some research every study I read that was a scientific study (not done online by a grow store) said LED’s could grow plants, but they NEVER did so better than an HID. Most were not even close (50% less yield with LED). NASA has some studies online and I have read a few published articles from the USA and Japan. LED research is big in Japan I gather.
The new Tri-Bands from HTGsupply.com are indeed comparable to an HPS. The light frequencies of their LED’s are best for plants. I say this b/c all LED's use red and blue but not the exact color (wavelength) that is best for plants. Many grow stores make cheap red/blue LED’s to save money which means they are biologically not so great for plants. The trick/gimmick is that the colors your eyes see (red/blue) are not exactly the specific one’s that a plant uses ‘sees’.

LED as supplemental light: Last semester I used one 120 W. Tri Band LED in conjunction with a HPS and the plants under the LED looked real nice, and did not have the stretched stems that the plants next to them had (all HPS light). The LED allowed me to add several square feet to the area where I grew sun loving plants in my grow area. If you use an LED with other supplemental light sources (Sunlight, HID and/or Fluorescents) I know you will be happy.

LED’s Grow plants through whole life cycle: I have used the 120 watt triband and grown plants (basil, lettuce, Coleus and of course others) in a grow tent. I grew these plants from seed to flower with out any supplemental light and without a problem. While I did have success, the 120 w Tri-Band was not as effective as the 208 watt (4 bulb) T-5 HO that I did the comparison too.(Obviously, with that much difference in electricity usage the T-5 damn well better beat the LED)

I think though when you look at grow area square footage the wattages compares at about ½, meaning that a LED that is 120 watt is comparable to a 250 watt HPS… this is I admit in my humble opinion.  I have not measured lumens or photons per meter squared. I know HTGSupply.com did comparisons with light output etc. but I don’t use their data. This semester I am just eye balling plant growth so that I can at least give my opinion, in the past a few E-mails I have had to respond I don’t know about LED’s. I do know the Tri-Band from HTGsupply.com work great. I did a test with pictures if you want to see (LINKto LED test). Therefore I recommend, to replace a 400 w HPS two 120 w tribands and 3 tribands to replace a 600 w hps. This will cost you more but you’d still be way ahead in heat and wattage used per hour. Depending on where you grow and how long you will grow this may pay for itself in electrical usage in time.

If you are buying a light now, I always recommend an HPS as I know that you will be happy with the results. Exceptions are 1) if you are concerned with heat and 2) you are concerned with energy usage and 3) you are concerened about having to replace bulbs every year or two (which you should do with HID)  An LED does not put out nearly as much heat, or use as much electricity, so it will be your best bet in some situations.

Good Growing,

Dr. E.R.Myers


E-mail -- Watering and Fertilizer

Dr. Myers,
     I have just one more question please. I need to know about watering and feeding the plants. At first I read just to keep them damp. I need to know how much to water them when they sprout and then after they are transplanted if you could. Also when to feed them. Thank you so much for all your help.

Hello again,
I have written about watering on the blog, you can do a search on the blog to find more info about it.  Any topic abou growing plants indoors you think of you can do a search on the blog.  If I have not written about it, E-mail me and I will answer your question directly and then eventually put that up on the blog.  I am trying to create a place where all types of people (beginner and advanced) can come share and get information about growing indoors… so the more questions I get the better for everyone.

Plants need water but I don't know about keeping them damp all the time. No matter what size plants you are growing you should water the plants until water comes out the bottom of the pot. However, you don't want the plants to sit in standing water so after an hour if the water is still in the tray, you will need to dump out the water. I usually suggest you let the top of the soil dry out before watering again. You can also tip over or pick up the pots to see if they are heavy with water or are light and need watering. The biggest problem people have is over-watering not under. Most people don’t realize the soil you provide your plants needs air space as well as water. I recommend allowing the top of the soil dry out. Also with hydroponics I usually recommend a timer so that roots are kept wet but can also get oxygen from the air.

You should give young plants a fertilizer that is high in nitrogen like 10-5-5 (Nitrogen is ALWAYS the first number in any fertilizer). When you want the plants to flower or fruit you should use a fertilizer that is highest in phosphorus (which is the middle number) like 1-5-4. The actual numbers are not as important as the ratio. You want the first number highest when plants are growing and the second number when the plants are flowering/fruiting.  I always suggest you follow the directions of whatever fertilizer you use. More is not better, it is usually worse (See my fertilizer experiment at the bottom of a past post) You will need to get a small measuring devise and a gallon container (I use a small graduated cylinder or a tea spoon and re-use milk jugs) measure the fertilizer as directed and water plants making sure they dry out between watering. If you are using soil (and worm castings as you mentioned previously) you may be able to use a bit less fertilizer than directed.

Good growing,
Dr. E. R. Myers


Tap water and chloramine

Dr. Myers,
   Is it o.k. to water your plants with straight tap water? Obviously all tap water isnt created equal, but generally, is it o.k.? Also, I've recently found out that my local water company uses chloramines. Should I consider buying spring water from the grocery to water my plants with?

Thanks for this E-mail, you are on top of your environmental goings on, good for you.
There seems to be some debate about this issue.  Some studies say tap water with chloramine is fine to drink and therefore water plants with.   There is a link below of some studies by our federal government.  A lot of other places say it is bad.  One thing I read was that chloramine is a mutagen and it can cause respitory problems if inhaled.  They mentioned showers but if you grow hydropincally you will also have water vapor in the air so you are putting chloramine in  the air your breath.   The bad news is that it is NOT as easy to get rid of chloramine as chlorine.  (this is one reason it is used, it will kill/ disinfect for longer periods in larger water treatment facilities)  With chlorine you could boil the water or just let it sit in an open pot over night. Neither of these remove chloramine. More bad news is that most of the tests were on animals, not plants so there is not much scientific info. out there about plants.

I was contacted (see first comment below) by a chloramine organization about many possible dangers.  If you are worried use spring water and contact your municipality.   There is also a petition to sign on the first comment below.  I was then contacted (without a name so we don't know their angle of interpretation) by someone that compared chloramines to chlorine.  Saying they both are bad so why not use chloramine since it is more effective in large facilities.   Since both chlorine and chloramines seem to have many negative side effects, it sounds like many municipalities need to find a new way to disinfect water such as using UV light.
 A possible option for your home would be to buy a reverse osmosis filter from HTGSupply.com.  This will remove some of the chloramine (no studies have tested how to remove it all)  The filters are expensive, but will get rid of most bad things in your water, save you the hassle of going out to buy water, using plastic jugs and if you are going to grow a long time and buy a lot of water it may pay for itself over time.

Good Growing,
Dr. E. R. Myers



Win a prize coupon by reading this...

I just wrote about expanding your indoor hobby outdoors.  I know like me, many gardeners grow both indoors and out.  I have to travel a lot during the summer and I have gardens in a couple of the places where I visit each summer.  This means sometimes I can only tend to my plants once a month.  Does anyone know ways to keep plants watered and fed over periods of time... like if you go on vacation for a week or more?  Maybe even advice for people like me that have to plant plants and leave them much of the summer until they are harvested when I come home.

I use compost, recycled potting soil mix from my indoor garden over the winter, vermiculite and other organic mixes like coir  in my garden to help plant roots hold water and this mixture helps plants through droughts as well.

I want to have a contest for the best answer to this question;
What is a trick you have successfully used to help keep you plants watered and/or supplied with nutrients for long periods of time?

Send your answer to me at askthedoctor@htgsupply.com The best answer(s) will be featured on the blog and you get a 10% off next purchse coupon from HTGSupply.com .  
(I have multiple coupons so runners up win as well.)

Good Growing,
Dr. E. R. Myers


Start an Outdoor Crop Indoors for Best Results

(I have written about starting plants inside for the outdoors before)

I actually started growing indoors to compliment my outdoor love of gardening. Living much of my life in northern areas of the USA I was always eager for spring so I started it early on my window sill as a child and eventually in a closet with a grow light later. I always will grow outdoors, it is the way of nature, but growing indoors has its benefits as we all know.

One real trick to starting plants indoor early is that you need to harden off your plants before putting them outside. Hardening off plants is the process, where you are preparing plants started indoors for the environmental conditions outdoors. If you don’t allow plants to harden off, they will be negatively impacted by UV light and other environmental stressors like wind, rain, and nighttime coolness. In other words, if you are not careful your plants will die days after you put them outside. The process of hardening off plants involves a transitional period in which plants are left outside in protected areas for short durations that get longer over time. You want them to get exposed to sunlight gradually over a week or so.

EVEN IF YOU THINK YOU CAN NOT HARDEN OFF YOUR PLANTS, there are a few things you should do to help your plants survive and thrive outside. The first is to have a fan on your plants. Of course this is just good growing, providing ventilation to maximize growth; but you should for several minutes each day put the fan(s) on high so the plants wave and bend. This will have the plants grow strong stems so they can handle wind, rain, and hail. It is also good to expose your plants to direct sunlight sometime when they are growing. If you don’t want the hassle of taking several plants in and out of the house each day, the least you should do is when they are very small, (seedlings) put a lot of plants on one flat and put it out for a few minutes each day until the plants are too big to take out in one trip. It would be best to gradually expose the plants to sunlight right before you put them outside, but if you can’t do that try to get them a couple hours (no more) of direct sunlight as they are growing. You should also transplant your plants outdoors on over cast days, multiple over cast days with drizzle is best.  Hot sunny days are BAD. 
Always water your plants well when you transplant as they will be stressed with the transplant. Try to disturb the roots minimally, if the roots are in the shape of the container break them up a bit so that they grow out and down and not around each other. Gently pack the soil around the roots. A trick I learned was to fill the hole ½- ¾ full then pull the plant up by the stem an inch or two (These are one month old strong stemed plants, not seedlings). This will make sure any loose roots are pointing down. Then, as with any transplant make sure the soil is firmly packed around the plants so there are no air pockets. I like to put the soil around the plants so that it drains toward the stem to increase water getting to the plant. However, for some plants you will want to mound the soil so that it drains away from the stem (fungus problems). If you are not sure, try both and other combinations to find the best one. If you have plants that are several inces or bigger you should have dug a hole at least twice as wide and deep as the container (minimal for good growing).  If you are growing an annual you can dig a hole and fill it with potting soil, compost  or other amendments. If you are a dirt grower like me you can just mix your usual indoor mix with the outdoor stuff. (Or ditch the outdoor soil and grow in 100% indoor mix the plants won't be limited by a container) If you just want to add something to some decent soil, worm casting and other organic nutrients are good to add because they provide nutrients with minimal risk of harming the plants. Chemical fertilizers are usually not good to add to the soil, they are usually dissolved in water and applied. If you put chemical fertilizer in with the soil you risk burning (and killing) your plants.

If you can take care of your plants often, you should water them and give them fertilizer often to enhance their growth. If you can’t attend to your garden often you should water and give them fertilizer minimally. If you water a plant a lot it will have a shallow root system but more above ground growth (higher yields). BUT, if you water a garden a lot for a period and then stop, the shallow rooted plants have a greater chance of dying due to lack of water. Vermiculite or organic mixes like coir will hold water and help plants through droughts as well as help drain water in wet times.

I wish you a successful summer full of outdoor good growing!

Dr.E.R. Myers


E-mail -- LED vs HPS

Hello Dr. E.R. Myers,

I would like to thank you for taking the time in providing everyone with all the knowledgeable information that is posted on HTGSupplysaskthedoc. I read your posts more then the daily newspaper. I am new when it comes to ordering from HTG Supply but I am quickly becoming a loyal customer.
My question is...
Which would you (personally) use between a 90 Watt UFO LED or a 400 Watt HPS for flowering? I am torn between the two. I know there are pro's and cons to both but am I just going to be disappointed if I try to flower with a 90 Watt UFO LED? The area (enclosed) where either light will be used is 4' x 4' x 7' feet tall. Also, what is the minimum and maximum square foot coverage you would use for both?
Hope to have a reply from you soon and thanks for all the input you provide

Thank you so much for the kind words. I really hope I am helping people be better growers. I know I am enjoying hearing and learning from people like you. The best compliment is telling a friend. (I read that at my dentists office)

I personally would go with the HPS for flowering. I should say I am just getting into using LED's and have used HPS's forever. I will be writing about LED's in the next few posts. ( Link to first part of LED test) I know you can grow plants with the triband from HTGSupply.com but an HPS would be better if you can handle the heat. LED tend to have a more focused light, meaning it comes straight down. the HPS if it has a good reflector will bounce MORE light around a LARGER area.

If you have issues with heat, or electricity usage (400w vs. 90w) then you should go with the LED (or maybe two in that area which still has less heat and electricity usage). Otherwise I think you will be very happy with a 400W HPS in a 4x4 space. You do have some sort of ventilation to get rid of the heat right? If not, you may want to think about a 250 W HPS. I think even this would be a bit better than one 90 W LED for flowering.  Even leaving the door to the closet/grow room open with a fan when the light is on should be enough to keep the temperature below 100F (which is when most plants are very stressed). With the 7 feet of height you can keep an HPS a few feet above the plants. You could grow short plants and keep the HPS further away (use mylar etc.) and this may keep the temperature by your plants down. If the HPS is too close you will see the closest part of the plant turn brown, due to heat stress. If you can, buy a thermometer with a Min. Max feature and make sure the temperature by the plant tops (closest to the light) does not go over 100F. The 90's are a bit high but ok. Ideally you want the day (lights on temperature) to be in the 80's and night in the 60's for most plants.  I hope this helps.

Please read my latest post about LED vs. HPS

Good Growing,
Dr. E.R.Myers

p.s. In general you want at least 1000-1500 lumens per square foot, and you can go up to 3000 lumens per square foot.


April fools

I wanted to run a post that said HTGSupply.com will give the first person to E-mail me a 1000 dollar shopping spree. But, a lawyer said that I could not because, “Some jerk might sue” for lying, misrepresentation, you name it. All because they do not have a sense of humor and understand an April 1, 2010 (Fool’s) joke.
So, to everyone but that jerk (Who I am not speaking to, ever), HAPPY APRIL FOOL’S there is NO PRIZE

Keep the E-mail"s coming.  I enjoy hearing from you!

Dr. E. R. Myers