E-mail -- How to use Molasses

Dr. Myers,

When is the right time to use Molasses in the growing cycle? How much should be used? I am using the Fox Farm nutrient package in soil-less mix. Do you add the Molasses to the regular nutrient feeding or add it to plain H2O that is
used in between feedings?
Hello and thanks for your question. I have not personally used molasses but there is a bit of information out there concerning molasses and/or sugar additives. Molasses is produced during the refining of white sugar from sorghum or from the juice of sugar cane. There is unsulfured molasses, but sulfur is a trace element so for plants I’d not use unsulfured molasses (Sulfur is not the most important thing so if you can only get unsulfured no biggie). Molasses is available in at least three colors/flavors light, dark and blackstrap. The degrees of color are a result of carmelation and how concentrated the molasses is. Light molasses is from the first boil of the cane, dark is a product of the second boil and blackstrap is a product of the third boil and before being sold as a plant supplement was mostly a waste product. This is the same story with coco coir it used to be a cost for a company to dispose of but now it is sold as a product. Maybe it is not so bad being green. If you find success in using molasses what a win-win; a former waste product that is sold to promote plant growth. If you are interested, I know blackstrap molasses does have another use, in brewing stouts and other dark beers.
Molasses if you break it down is a plant derived substance that contains potash, sulfur, and many trace minerals which can be limiting factors, it has a lot of carbohydrates (small carbohydrates are called sugars) which are an energy source for plants and/or soil microorganisms and in some studies the sugars act as a chelating agent, which means it will help plants to absorb nutrients that otherwise they could not.

There are studies that show the benefit of molasses is it provides sugar to the plant and/or soil microbes which will promote growth either way if nutrients are a limiting factor. I want to stress as I have in the past that if you want to improve growth the first and most importing thing is increasing the amount of light ALL your plants get, not just a few directly under the light. If the molasses provided a limiting nutrient you can apply it in any and all stages of plant growth at a tablespoon per gallon. But, read the limits of molasses below before you run to the store and buy up all the molasses.

Limits of molasses: I understand that many people think that adding molasses the last few weeks of flowering/fruit production will increase flowering, or that it might improve taste. Since the sugar will be metabolized (completely broken down) in the mitochondria of plant cells into CO2 and H2O and energy, it must be some trace mineral in molasses itself that alters flavor. I found no scientific study that showed improved taste due to added sugar. I did read one scientific study that said adding various sugars had no affect on fruit flavor good or bad.

While there certainly are benefits to using molasses, if you add the molasses (sugar) you do need to watch for unwanted species of mold or other pests growing in your soil . You are creating an all you can eat buffet, and you may get undesirable microorganisms in your medium.

I have also heard people suggest you foliar feed plants to get the benefits “right in there” the truth is the stomata or pores in leaves are designed to convey gaseous CO2 and H2O molecules and I don’t know how the sugar would move around inside the plant if it entered via the leaves. Also, since the stomata are on the under side of plants most water nutrients will wash off the plants if not sprayed on the underside. On the other hand, the roots are an organ designed to take in nutrients that are dissolved or soluble in water. Whether molasses can get into the leave or not can be debated but you can not argue that if you foliar spray molasses you are creating an environment that many harmful organisms can thrive in I would never recommend spraying sugars of any kind on leaves or flowers in any stage of growth.

I think there is a lot of truth in the school of thought that the sugars/carbohydrates in molasses actually feed the microbes in the soil, or hydroponic tank, and that this increase in microbe metabolism and its supply of available nutrients to the plant is what improves growth. Either way, it seems you can add molasses a table spoon per gallon at any stage of the growth cycle so long as you don't get harmful bacterial or fungus. I would be interested to hear if it makes a difference from any of the people that read this blog, maybe you could try using molasses on some plants and not others. The problem I read in many personal experiences with molasses on the web is that they used molasses on all plants and they were 'great', so therefore molasses is great? Nope, you don’t know if it was the molasses, genetics or the light from HTGSupply.com you are using that gave you the environment to be a good grower. A test with a control group is needed to prove it, you should use molasses in ½ the plants (that are all from the same mother plant or F1 generation hybrids at least) and compare them to the ½ you used molasses with.
That should answer the E-mail but in my next post I will continue discussing molasses in more detail, stay tuned!!

Good Growing
Dr. E.R. Myers


A Proven Fertilizer for Success - 1

Many of the E-mail’s I get are people asking me what fertilizer I use, or what the ‘best’ fertilizer to use is. The truth is it depends on the environment you create to grow in (Consider the medium plants are in, average temperature, high and low pH, source of water etc.) and most important what species of plant you grow. I can say that one thing that seems to be true in all cases is that organic based nutrients are beneficial and seldom harmful when used as directed. Keep in mind I have repeated a previous experiments (bottom of post) showing that adding more than the directed amount of nutrients actually SLOWS growth.

If you are starting out or want to try something different that you know will work… I like the Fox Farm products and recently I have been using a fertilizer that contains many beneficial organisms. Peace of Mind from Fox Farm

I use this indoors mixing about 1/4 cup of Peace of Mind with my soil/perlite  mixture when I potted up into 1 gallon containers. This semester my plants grew better than they have in a few semesters. This excellent growth continued even without adding more Peace of Mind as I potted up into 5 gallon buckets of soil mixture. I figured any microorganisms in the 1 gallon would grow and increase in number in the warm, moist soil waiting for them in the 5 gallon bucket. There was indeed continued good growth as the plants continued to grow for a week in vegetative and then begin to flower using my standard fertilizers. The plants had healthy looking dark green leaves through out the grow cycle (Seed to flower) where as in the past two grow cycles I had been dealing with some yellowing and necrosis as the plants began to flower. I lost one plant last semester and a few others I was worried would not make it. This semester I had none of that, which may mean I had a nutrient deficiency, or the plants had a weaken immune response and the beneficial organisms and/or nutrients helped boost the plants immune system.
I also used Peace of Mind from Fox Farm outdoors for my landscape plants. I had a great year in both growth and flowering for all the plants that I used the Peace of Mind from Fox Farm- with. The greatest example may be that the Bradford pear tree in my back yard is having a monumental year first with flowering and now in the fall fruit production. In fact it is sort of a pain, never in the 7 years I have lived here has the tree been dripping with pears as it is now. They cover the ground with the leaves and stick to your shoes so you have to watch for them. I sweep and rake them daily or face the consequences of the damn fruits squished in my shoes. There are many species of birds, squirrels, raccoon and opossum eating fruits on various day and night shifts but still so many fall to the ground and are left neglected to rot. I know comparing this tree to another in the front yard and a few around the block that did not get the fertilizer is not a scientific experiment, but I think there is a real benefit to all plants to have microorganisms living in the soil with them. After all, these organisms (plants, soil fungi and soil bacteria) evolved together and therefore why would anything be better for the expert or average Joe grower? If you want to grow ‘organic’ and be a good grower you will have to be mindful of beneficial organisms.

If you are looking for something to try, I am very happy with Peace of Mind from Fox Farm and I have used and will use again many products from Fox Farm all of which I get from HTGSupply.com.

Good Growing,
Dr. E.R. Myers


Day light savings, a timer and your life schedule

This year I have my home garden flowering 10 pm ‘off’ 10 am ‘on’. I like this because a couple days a week I get home at 9 and I like to unwind by watering, caring or just staring at my plants. With day light savings, I went down stairs after work and the light was OFF. Ohhh man. It took me 3 days to remember to alter the light back to my schedule and I figured this was a good topic to write about.

So, what is the best way to get your plants back on your schedule? Well, you could just leave the light at 9 pm ‘off' 9 am ‘on’, but I don’t like that. So, the second choice is deciding if you are you going to shorten a day or lengthen a night. It won’t make or break your growing but I would recommend having a longer night. I say this because as you may know plants keep track of day length with a molecule called phytochrome. There are two forms of phytochrome, light and dark. Light energy makes light phytochrome, and light phytochrome changes to dark phytochrome without light. The ratio of light to dark phtochrome molecules is what triggers a plant to flower. So, if you lengthen the day by an hour, you will have more light phytochrome than dark which may confuse the plant and if you are already stressing plants with too much nutrients, or light contamination at night etc. this added little stress might be the final straw that makes your plants have problems.

What I did is changed the on time an hour, so that the light would come back on at 10 am. This gave my plants a 13 hour ‘night’, which if anything would speed up the flowering response. Then, the next day with the lights on I moved the lights off time back an hour and now I am back to my original time of on and off.

Good Growing,
Dr. E.R. Myers


E-mail - Preventing Unwanted Seeds or Pollen Protection

Dear Doctor Myers,
I'm having a horrible time with my plants going to seed. My flowering room and vegetation room are separate. I don't know when or where the pollen has come from and I really don't know what to do. I will have the flower room empty very soon and can clean the room but it's lined with Mylar. How do I clean the pollen out of the whole grow room?

  Thanks for your question.  There are many reasons to prevent seeds first would be to ensure a true breeding line. To do this you will need to make sure there is no pollen (plant equivalent to sperm) in the room where you are inducing flowering. The easiest way to do this is to remove the male part of the flower (plant sex link), or male flowers or male plants, depending on the species of plant you grow. If you grow plants that have a perfect flower (male and female in same flower - like peas) you will have to remove the male part from every flower. If you have both male and female flowers on the same plant you can remove the male flowers but both of these situations you will have a hard time not getting seeds if you are not consistently and accurately checking your plants.. If you grow plants that are male and female (separate sexes) you can remove the entire male plant. A problem with plants that have separate male and female plants is that you may have a plant that is a hermaphrodite (has both flowers usually a small number of male flowers on an otherwise female plant), these hermaphrodites can be due to genetics or stress from high heat, or light getting in during the dark cycle, or poor nutrients (check for these problems in your garden as all can cause hermaphrodites)... If you think you have hermaphrodite plants, you may want to start over with different seeds to be safe.

Pollen from some plants can float in the air for days. You need to wipe down the Mylar and all surfaces in the room with a cleaner that has ammonia to kill any pollen. High temperatures and moisture can also kill pollen, so after you wipe down the room, try to have very high temperatures if you can for a couple days (leave light on with out exhaust fan for example). And spray the room with a water bottle once a day. Pollen usually is only viable for a couple days at warm temperatures.
I have written about pollination in previous posts

A carbon filter  might help cut down on pollen production, but it could also blow pollen around the grow room and make your problem worse if you have the air blowing across your plants like I have recommended in order to increase airflow and the growth rate. However, If you vent the carbon filter air outside the grow room, preferably outside the building, that might cut down on pollen.
Good Growing,
Dr. E.R. Myers