First plant

Now is time to put in the plants. I had one Jalapeño plant that was on death's door, so I decided it would make a good first candidate for the system.

I will be using a type of deep water culture (DWC) system, which means the roots of the plant are suspended in a nutrient solution. This usually consists of a reservoir of nutrient solution with an air supply. Due to frequent power outages, such a system that depends on 24/7 electricity is not an option, so I'm doing an experiment, the roots will be suspended in the air, but just touching the surface of the water. Hopefully they will get enough air while still being able to reach the nutrient solution. I've seen this demonstrated before and apparently it does work. we will see.

First I cut open a 1.25 liter soda bottle to serve as the reservoir, and put a Styrofoam cup with holes poked in it to serve as a net pot. For a growing medium I am using cotton balls and coral chunks that behave much like hydroton, which i found washed up on the beach.

Hydroponic nutrients are not available here, So I bought some 20-20-20 in the capital which was sold by kilogram. Standard fertilizers like this lack something called micronutrients, which is what sets hydroponic fertilizers apart. However, if you look closely on the bag to see what its made up of it is possible to find regular household fertilizers that do in fact have micronutrients. One of the keys is magnesium, this one's got it.

Next, I take the plant out of the soil and wash all the dirt off of the roots, then wrap whats left in wet cotton. Afterwards, center it in the grow medium.

And we're ready to grow! I started spray painting the bottle so as to keep algae from growing inside, but ran out of spray paint. So later on I wrapped the bottles in foil and it seems to be a good solution. I even put in a bluetooth speaker to play music for the plants. Might sound crazy, but its been proven on many occasions that music aids plant growth. The same with talking to them.

 Finally, here are the foil wrapped reservoirs, with some newly added Oregano plants.

Setting up the grow light

In my case, we were able to find a few light bulb sockets very cheap at the hardware store on the island. Its a simple screw in fixture with two prongs for a regular plug. I got a pack of 3 6500k CFL bulbs, and one 2700k bulb, since we plan to grow mostly herbs the light requirement will be low, and mostly for blue light. We're only using about 60 watts in total at this time, maybe in the future we will add more bulbs or brighter ones.

We used a segment of a snap-together metal shelf as a frame for the light, and used electrical tape to connect the sockets to the frame. Also using this same tape to ensure the metal prongs were not in contact with the frame itself.

After that I rapped the whole thing in foil to provide a reflective background. Again, using tape to keep the metal foil out of contact with any wires or metal.

We bought some wire, and wired them together in sequence. This is a bit technical, so I'd advise not doing this at home unless you have some electrical knowledge. We stripped the ends of several segments of wire, and tied the ends to each prong of the sockets. Two lights on each side and 4 in total. We used black for hot and white for not. Then for the plug we wired them onto the cord we cut off from a broken floor fan.

To my surprise and great pleasure, it worked the first time. We then hung the light from strings above the shelf that would become the plant area, and made a curtain of foil all around the area to focus the light and spread it evenly through the growing area.

By the end of the project, the lamp was producing 5,000 lumens at the leaf-height, evenly across the growing area.

What plants need from your grow light

Plants are fascinating creatures. We know that sunlight is best, but why? what makes sunlight superior to artificial light for growing plants? Is it magical fairy dust that falls from sunshine and rainbows? no.

Sunlight is intense, direct sunlight can be as powerful as 120,000 lumens. It also contains the entire spectrum of visible light. But do plants really need ALL of that? well, no actually. Sunlight feeds all the life on earth, plants only use a small part of that. Photosynthesis is the basis of a plants life cycle, and it happens when chlorophyll cells in the leaves absorb light and a long with water, Co2 from the air, and nutrients absorbed through the roots, produce food for the rest of the plants cells, enabling it to grow and produce new tissues, even flowers and fruit.

An interesting fact, is that photosynthesis in most plants requires only two "colors" as we know them of the light spectrum: Red and blue. (They use small amo
unts of other colors as well but the majority of the light they need is red and blue) That is why some grow lights on the market, especially LED's which can be tuned to specific wavelengths have an eerie purple glow.

This need changes through the cycle of the plant though. During the vegetative stage, that is when the sprout is new and growing only leaves, it needs more blue light. When the plant starts to bloom and produce fruit, it gradually begins to need more red light. Using only blue light will result in a short but very leafy plant, using only red light will result in a tall spindly plant... I guess. Supposedly they figured all that out in a lab somewhere. I'd love to do some experiments like that but I don't have the time or money. mostly money.

Most light bulbs are labelled as to the color of light they produce. This is known as the "white balance" or "Color temperature". This rating is displayed in degrees kelvin, or just K. It has nothing to do with actual temperature, just color. The lower the number the more red the light produced is, the higher the number the more blue light is produced.

"daylight" fluorescent bulbs usually have a rating around 6400 or 6500k. This is closer to blue and is perfect for plants in a vegetative stage. "Warm white" CFL bulbs will usually have a rating around 2700k, which is beneficial for the flowering and fruiting stage. I've found the most success using a mixture. My current setup has 3 6400k bulbs and one 2700k. I used an LED panel once, but got the best results when I placed two 6500k tubes next to it.

Now when it comes to intensity, more is always better. Unless you're at risk of burning your house down you can't have too much light. Heat will damage the plants, as will UV light, but mere brightness isn't something you should be worrying about. The amount of light a plant needs changes through its life cycle. Seedlings can be started with very little light, usually one bulb is enough, but to grow to full cycle and produce fruit requires a lot more. I would say the minimum for most plants is 5,000 lumens for vegetative growth and 10-20,000 for flowering and fruiting. Thats a minimum, so adding more lights and more intensity will show immediate results and faster growth. There are many apps for smart phones that use your phones camera to give you a light intensity readout in "lux". Lux is basically the number of lumens reaching the sensor, so hold it where you plan to have your plants and that should tell you how much light is reaching their leaves.

60W CFL grow light, with foil tent

The closer your plants are to the bulb, the more light they will get, and you can also help to focus the light from your bulbs using tinfoil and home-made reflectors. A few sheets of tinfoil can easily double the output of your lights. I was able to get 5,000 lumens out of only 60 watts of CFL bulbs by making a "tent" out of tinfoil and electrical tape. In another post, I'll explain how we built it and include pictures.

What are the different types of grow lights?

There is no shortage of sunlight here in the Caribbean, but as explained in another post there are compelling reasons to grow indoors. Professional grow lights can be very expensive, but you might be surprised what you can come up with on your own, so long as you are aware of a few basic principles.

Firstly, when it comes to light more is always better. But intensity is not at all the only factor. You want lights that will be efficient and not produce too much heat, which could risk burning your plants. There are several major types of bulbs each with their advantages and disadvantages.

1. Incandescent
These are your typical household bulbs. They produce a yellowish-white light and are very cheap and very common. They are also completely useless for growing plants indoors. They are terribly inefficient, giving off 80% of their energy as heat and only 10-20% as light. They get extremely hot, they don't last long, and the light they produce in no way resembles natural sunlight. The average household incandescent bulb uses 60-100 watts of power and only gives off about 800 lumens.

2. Fluorescent
Fluorescent bulbs are nothing new but are gradually replacing incandescent bulbs even in household use. They are many times more efficient, converting about 80% of their energy into visible light. They get warm, but not so hot that you can't touch them with your bare hand when they are on. This means little or no risk of damaging your plants if they grow into the light and touch the bulb. The light they produce much more closely resembles daylight, and they are inexpensive and common in many countries. Fluorescent bulbs come in many sizes, shapes, and colors. Wattages can vary greatly. A 20 watt bulb can produce as much as 1,000 lumens.

3. Metal Halide
These are common in hydroponcis and indoor gardening, as they have a very high output. But they also use a lot of power. They are quite efficient, the only problem is they don't come in small sizes. They tend to be in the 400-1000 watt range and produce enough light to seem like there is a second sun in your closet. They get hot though, so if you go big with these you should think about cooling systems as well. Metal Halide bulbs are commonly seen in older street lamps and give off a blue-green light.

4. High pressure sodium (HPS)
Also common in large scale gardening and hydroponic systems, Very similar to metal halide bulbs, but using a different chemical reaction. They are equally bright, but slightly more efficient. The difference is mainly the color, these are bright yellow, usually these are used in combination with metal halides.

5. Light Emitting Diode panels
This is a new technology on the market of indoor gardening, I have experimented with it somewhat with mixed results, but I believe that it is by far superior to other grow lights. It also costs more. LEDs are extremely efficient and almost never burn out. They use a fraction of the electricity of a fluorescent bulb, but give off far more light. 120 watts of LED lights can easily be enough to grow large plants like tomatoes and chili peppers to fruiting stage. The light output may be deceptive, as they are often tuned to specific color spectrums. Be careful with high powered LED systems though, as looking directly into them can be like looking at the sun and damage your eyes. This is a good thing for your plants though.

So how do you decide what to use? Well I just use what I can get my hands on. In my case the only thing available was CFL fluorescent bulbs. But what really matters is providing what the plant needs.

Hydroponics with limited materials

One of the big challenges of designing a hydroponics system on an Island like this one, is the lack of materials. Some countries have big hydroponic supply stores where you can buy everything, even pre-made high end systems. In other places, you can still find nearly anything you need on the internet and have it shipped to you. Not so here. Where I live we don't even have a mail system, we can't even get letters mailed let alone packages. Also, even traditional garden centers do not exist in this country, gardening just isn't a thing. Farming is a thing, but here farming is walking into the jungle with a machete and chopping down any plant or fruit you need that just happens to be growing there.

Hardware stores, or "ferreterias" in spanish are a good resource. Here you can get basic materials like wire, pipe, tape, light bulbs etc. Nothing is labeled for gardening use so you need a bit of knowledge to know what to look for. Grow lights are not too difficult, My wife and I built our own grow light out of a metal shelf piece, tin foil, wire, and CFL bulbs. It has yet to catch fire, so thats good.

Selling seeds is rare also, so you will have to find most of you seeds in the wild, or take cuttings from the wild or from your neighbors (yes, I ask permission first). People here don't know Jalapeños, but I love them, so I went to the one market that sold them and bought the most shriveled up, over ripened Jalapeño they had. I got some strange looks for buying one single rotten pepper, but it was full of viable seeds. Sadly most of the sprouts died from salt and wind exposure, which is part of my inspiration for doing this hydrponic project. I also plan to grow lettuce, spinach, oregano and other herbs that are not available from the markets here.

I was able to find fertilizer in the capital on the mainland, but had to know what I was buying. Hydroponic nutrients can't be found here so I had to buy some other fertilizer by the kilogram, i'll go into more detail in another post.

In all I think I spent $10-15 on the entire setup, but it took some work and some creativity. In future posts I'll explain in detail each of the steps.