Ask Ed

What’s your advice on reflective surfaces for increased light efficiency? Which do you think is better, reflective materials such as Mylar or using solid white paint on the walls? Is there a paint designed to be a better light reflector?

Gunnar W.,
Address Unknown

Plant growth is fueled by light so the amount of light a plant receives determines how big and fast it grows. All light that doesn’t reach plants is wasted. For that reason any light that escapes the plant area should be reflected back to the canopy.

This problem is usually more acute in small gardens than large ones because in small gardens the ratio of perimeter to area is much higher than in large ones. Thus, light is more likely to fall outside of the plant area in a small garden than in a large one where there is a bigger target for it to hit.

There are many ways to direct light back to the garden. If part of the garden is contiguous to a wall, it is easy to make the wall a reflector by painting it flat white. Flat paint diffuses the light as it reflects it, distributing it evenly. Shiny enamel surfaces reflect light as hot spots so it is distributed unevenly. Sometimes titanium white is available. It contains highly reflective metal and is more efficient as a reflector than regular paints.

Gardeners have a large choice of reflective materials. These include Mylar, aluminum foil, Styrofoam board, white or silver polyethylene, or white cardboard.

Mylar white polyethylene plastic and aluminum foil (dull side out) are easy to hang or tape to a frame. Initially, Mylar is more reflective than plastic or foil, but it spots and stains easily and its electrical charge attracts dust. Foil and polyethylene are easily washed and inexpensive so they can be replaced without busting a budget. Styrofoam board is extremely reflective but gathers dust and should be wiped clean after each crop. It’s easy to install because it is lightweight and easily cut to size. White cardboard shares many of those qualities but eventually gets sloppy from moisture spills and sprays.

If your reflector is not well designed for the space, it may spill lots of light outside the garden to the sidewalls. Placing an aluminum foil curtain around the perimeter of the reflector can ameliorate this. It can be custom designed to grab and reflect light. To make a curtain that holds its shape, use a heavy-grade foil or, for more precision, use a thicker material such as the aluminum disposable baking pans are made of.

Your small investment in time and material will have a great payback, especially when you consider how much it costs to generate light. The additional light the plants receive will result in more vigorous plants that produce a higher yield.


About three years ago I decided I’d had enough with dumping chemicals into my system and began to replace the unhealthy elements in my diet with organic materials. I quit eating red meat, refined sugar, processed foods?I’m sure you get the picture.

Part of this whole scenario was that I quit smoking pot, too. I’d smoked fairly consistently since I was 15, for about 25 years. In the past year I tried to smoke a couple of times. I found that my lungs reject the smoke. I cough uncontrollably and feel short of breath for hours after even a single hit. Then I got the idea that eating it would probably work so I’ve added some to baked goods once in a while to enjoy the high.

Last Sunday my husband and I went to a friend’s house. He broke out the weed. The three of them passed the bong while I sat there feeling sorry for myself. Our friend then offered me a bit of butter that he’d soaked weed in, I said yes and proceeded to spread it on bread. The only other thing that I imbibed that night was home-made chicken soup.

After about two hours my heart began to race while I was lying down watching a movie. Within a half hour I tried to walk and fell down. I blacked out when I fell and was unconscious. I came to with my friends standing around me and fell down, unconscious. They said my color was dark gray and my lips were blue. They thought I was OD’ing. After I came around I threw up everything in my stomach but it was another 45 minutes before I could move.

Now it’s two days later and I still feel the effects in the form of nausea and light-headedness. I looked online and found no reference for OD’ing on THC. Is it possible that I suffered an allergic reaction that was so strong it almost killed me?


I consulted about your case with Dr. Mike Alcalay, who has studied the effects of marijuana. The adverse reaction you had to the butter occurred as the effects were reaching their peak, which occurs one to four hours after ingestion.

We don’t know the full circumstances but from your description we believe that you exhibited symptoms of a substantial overdose: inability to move, increased hear t rate, and loss of consciousness. You may well have also suffered from a panic reaction as the symptoms became apparent.

Tachycardia or the sensation of racing of the heart rate is a common experience with first-time or occasional cannabis users. At least in ordinary circumstances this effect goes away with regular use, usually after a week or two. Interestingly, as the heart rate speeds up (usually up to 25% of normal in most people), the blood pressure actually falls?this has been documented by many patients who use marijuana for their hypertension.

You ate the buttered bread on an almost empty stomach so a much higher percentage was digested than if you had eaten it while full. The digestive blood passes through the liver where THC is converted to 11-hydroxyl cannabinol, which is at least as active as delta-9 THC. This potent mixture can build up to much higher levels in your blood and brain than would happen if marijuana smoke was inhaled. Higher levels can also build up when using concentrates such as hashish, oils or tinctures.

Your reaction does sound quite extreme; even lab animals that are given massive overdoses usually react by simply curling up in a corner and sleeping it off. It may be an allergic reaction, but more likely it is that you have developed a sensitivity to cannabis. When combined with a very strong dose, this made for a scary and unpleasant experience.

After such a traumatic incident, you may wish to abstain altogether. However, if you do decide to experiment, you obviously need only a very small amount as your tolerance level is very low. Smoking is the easiest way to selftitrate in small doses, and the onset is much quicker than eating, so you know when you have enough. When eating cannabis, there’s no way of controlling the dose once you ingest it. If you do try it, inhale it, don’t eat it.

I would not recommend marijuana because of your sensitivity. However if you do choose to try again, be very conservative. Take care with how much you inhale. Dr. Alcalay recommends starting with as little as a half-toke in the beginning. Wait for it to have an effect before trying more.


I live in the U.S. Is ordering seeds here illegal? How much does the government know when Americans purchase seeds online? Do they know, and if they do, is it technically legal for them to pursue me? I also want to buy a grow book, Closet Cultivator, but can’t seem to find it at any stores right now. I would purchase it online, but I don’t want to bring any unwanted attention to myself.

What should I do?

John B.,

Viable marijuana seeds are illegal in the U.S. If you are caught with them you could be charged with possession and an ambitious prosecutor may try to overreach and charge you with cultivation.

That being said, it is very difficult for the government to detect seeds crossing the border. They are very small, are usually well packaged in an appropriate unsuspicious package and they have no odor. Further, it is illegal for the government to open first class mail without a warrant.

There are several internet sites that rate seed companies. A few good sites are: