Tuesday, October 20, 2009

LED Grow Lights

As winter time fast approaches, the summer window sill season is coming to an end for many of the plants that require more light. This year however, I might be trying a new artificial lighting system, namely LED grow lights. Traditionally, Metal Halides (MH) and High Pressure Sodium (HPS) lights have been used as they have a high output of particular light frequencies which plants need.

As mentioned in previous posts, fluorescent lights typically do not have enough of an intense output to provide the necessary requirement for high energy plants like tomatoes. This means that if you are serious about growing, you will need to invest in a lighting system that will create the necessary lighting requirements for the species of plants.

But there are some drawbacks to these high output lighting systems. The efficiency of the lights themselves are relatively poor, which means a few issues coming to light. One is that the energy not being used for light is primarily turning to heat requiring some form of temperature control in the room to prevent scorching. This is exceptionally true for new growth plants. The other concern is the expense of having these lights operating. If you have a good size garden, say 50 sqft, you are looking at requiring a wattage of about 25W/sqft with 3 - 400 W MH lamps. If you are running this an average of 14 hours per day (16 hours during vegetation and 12 hours during flowering) this adds up to 16.4 kWh per day. Using the US national average for April 2009, this is roughly $60 USD per month. The fact of the matter, is that it adds up pretty fast.

Over the course of a year, that is nearly $750. Starts to make you wonder whether your tomatoes are really worth that much to you!

Why I am thinking of switching to LED Grow Lights


The first reason to go with LED grow lights is the control of the light spectrum used. Plants primarily use blue and red light for synthesis (hence the reflected green color). LED grow lights have the benefit of controlling this spectrum very well.

LED grow lights are exceptionally economical due to the efficiency of transferring energy to light energy instead of heat. LED's require approximately 75% less energy compared to MH or HPS lights. This would be an annual saving of approximately $500 per year.

LED grow lights also last significantly longer than MH or HPS grow lights. A Metal Halide light bulb typically has a rated life of approximately 15,000 hours and the High Pressure Sodium has about 25,000 hours. LED's on the other hand are twice as long as the HPS lights at about 50,000 hours of useable life.

Since the heat is exceptionally lower for the output, there is also less of a need for controlling the temperature of the room. This can also be additional savings with respect to air conditioning cost as well.

The growing results in studies speak for themselves. See this article on NASA and it's development for space farming with LED grow lights.

So, all things considered, I am thinking I might make the switch. I'll keep you posted.

Keep growing!

Friday, August 21, 2009

An Indoor Garden Showcase: Stevia!

It wasn’t always a plant I loved. To be clear, I was raised on a diet of ice cream like many kids across North America today. The sweetness of this plant was not comparable to the overwhelmingly refined taste of white sugar and maltodextrin, but as I am becoming increasingly conscious of my own health and working to reduce the amount of sugar I am consuming, it has become a great help in reducing those sugary cravings.

Throughout the last few decades, there have been controversies surrounding the use of stevia and its safety. For those who understand the extremely negative effects of artificial sweeteners like aspartame this has seemed rather counterintuitive and concerning regarding the hypocritical nature of those decisions. More recent information however has led the WHO to conclude that it is safe for consumption, in fact with health benefits. Since this study, many of the previously banned statuses have since been opened for public use.

I’ve been consuming it for a few years now, mostly in the expensive store bought liquid extract form, but have recently been inclined to start growing it myself. So, for all you health conscious gardeners, if you haven’t yet, you should give this little guy a chance.

Stevia: A Member of the Garden.

This baby is a perennial which is convenient and every time you harvest it just seems to come back a bit stronger. Do not let its South America heritage fool you; it has great potential to be grown in North America as well. It is a hardy plant that can be let go to seed and it will multiply easily. However, unless you are trying to build a family, harvesting is best done prior to the formation of blossoms to maximize the sweetness. After this time, there is a slight bitter after taste which is completely avoidable. It can grow as large as 30 or more inches, so ensure you have a good amount of space for this bushy fellow.

To ensure a quality plant, it is better to start from an existing plant. When you are at the greenhouse, rip a leaf off and chew it up! It should be sweet. Sweetness between plants varies, so try to pick the one that is best for your indoor garden.

Harvesting and Use:

The fresh or dried leaves of the plant are added to your food/drinks. A favorite of ours is adding the leaves in with our drip style coffee and having it naturally sweeten our drinks in the morning. The leaves can also be dried and crushed/blended into a powder and mixed in with your foods.

I should say that we still don’t exclusively use stevia grown from our own indoor garden. There is a refined stevia powder that is more potent then the leaves themselves and this is typically used for baking and as a stronger sweetener. From my reading, the stevia leaves will typically have between 10-15% of the “stevioside” while the refined extract is typically between 80-90%.

Still, for warm drinks, the subtle flavors in stevia are unequivocal to sugar and I recommend the home grown stevia.

Tuesday, August 11, 2009

Indoor Garden Climate, Light, Nutrients, Watering and Pests

Last post I talked about vegetable selection, soil and containers/pots to use. I will continue by talking about Climate, Light, Nutrients, Watering, and Pests!

Indoor Garden Climate and Light Suggestions:


As mentioned, additional light will be a necessary accessory to your indoor garden. There are many different ways in which this can be done depending on the quality of the vegetables you plan on producing.

For the larger leaved vegetables such as spinach, lettuce, cabbage, beets etc. are capable of doing quite well under fluorescent lights with full spectrum or aquarium lighting. Standard fluorescent lights do not have sufficient amounts of the red and blue spectrum and will likely produce meager results. These full spectrum/aquarium lights are readily available in home and garden stores and won't cost you much extra. Cheap 4' light ballasts are also available and can be picked up for relatively cheap. The higher the wattage of bulbs, the better you can expect the plants to do. It is best to have the fluorescent lights adjustable in height as you will want to keep the lights 15cm (6") from the top of the plants. This can be done by using a light hung by a chain which can then be moved up to the next rung when the plant grows.

Having the lights on a timer will work well, set to ensure that a total of 8 hours of light is met. If by a south facing window, have the lights come on at 5 pm or so until 9 pm to give them the extra boost of light required. The plants can also be grown in a basement, however, the timer should ensure 10 hours per day as the light quality is not as good as sunlight. For the broader leafed vegetables, moderate success can be achieved with solely the fluorescent lights.

For tomatoes, peppers, beans etc. which require more light, you may want to think about using a more powerful light to ensure that it does better. I will discuss more advanced lighting techniques in another post however, in bright rooms I have seen tomatoes do relatively well with fluorescent light supplement. However, it is nearly impossible to have a successful yield if using fluorescent lights as the sole light source for these light intense plants.

The broader leafed plants will do better under cooler growing conditions (15'C or ~ 60'F) while the tomatoes and peppers will do better under the warmer (20'C or ~ 70'F) temperatures. In all cases, a bit of air circulation can go a long ways to ensuring the plants are breathing sufficiently, especially during the daily photosynthesis periods. In the evenings, transpiration will produce marginal amounts of carbon dioxide, but in small amounts that will not need additional air circulation. Regardless, air circulation is optional unless you have a dense crop being grown.

Nutrients, Water, and Pests

Fertilizer will be necessary on a regular basis (weekly) as the growing plants will be eating like a teenager. I prefer a natural fertilizer such as seaweed based or fish emulsion, however other options are available from your local home and garden shop. Whatever you do use, be sure that you do not add to much as you can cause some serious problems to your roots and destroy your plants. Fertilizer is not like steriods, you cannot force the plant beyond it's potential just ensure it is getting a balanced diet.

Water levels are important to keep a close eye on. Unlike the indoor herb garden I talked about in my other blog, vegetables are a bit more selective about their environment. Ensure that the plants do not become too dry by watering them regularly. Like you, the plants will not survive without water for long.

On the other hand, do not over water them! Over watering is more common of a problem and will have as much or more effect on the plants. If you see any mold, think about your watering schedule. All the plants may require a bit more or less water than the others so keep an eye on them. If your plants are looking droopy, it is likely in need of a drink. If they are dropping leaves or are not seeing much growth, watch out for over watering. I might get around to discussing hydroponics in a later post.

Growing indoors eliminates many of the pest problems that you typically get outside. However, if you do see any pests such as aphids or meal worms, there are organic soaps which can be used to get rid of them. Do this as soon as you notice them to avoid any spreading to other plants. If used too close to harvest time, ensure to give all your vegetables a good scrubbing before you eat.

All in all, it is a great project and a lot of fun to maintain. Fresh vegetables all year long is a great joy and helps getting through the winters. It's also a great project to have if you have kids and will teach them a lot about how plants grow!

Have fun!

Indoor Garden of Vegetables!


So you want to set up an indoor garden? That's great!

However, we do need to consider and plan a bit before we get started. In this post I will discuss each of the following:

  1. Vegetable Selection - what veggies should you grow?
  2. What type of soil should you use?
  3. What are the best containers and pots to use?
  4. What type of climate and light do I need to provide?
  5. How to maintain nutrients, water levels and avoid pests.


Vegetable Selection and Suggestions

A common problem with the indoor garden is finding sufficient space. With this in mind, it is often beneficial to look for miniature versions or vegetables that you can eat while immature. Some examples of this would be baby greens, baby carrots, spinach, short-vine cucumbers, as well as cherry and/or grape tomatoes.

Personally, I tend to mix it up so new flavors are mixed into my diet throughout the year. I tend to primarily cycle through these vegetables:

  1. Spinach is a staple in my diet, so I keep this going year round. It is easy to maintain a steady crop by sowing a new row every couple of weeks to replace the row you are currently consuming. Spinach will reach maturity in as little as 4-6 weeks from seed.
  2. A few radish seeds can be planted weekly in a similar style to the spinach.
  3. Tomatoes. Requires a large amount of light but worth it. See the light section to get a better idea of what that means. Cherry and grape tomatoes tend to be the best for indoor gardening.
  4. Peppers also require a large amount of light and are paired well to grow with tomatoes. Smaller varieties like the hot peppers or sweet peppers are best, but bell peppers are doable as well.
  5. Baby beets are best to avoid long wait times and reasonable size. These will take 6-8 weeks till mature, but a delicious compliment to your vegetable dishes. Great with fall and winter meals.
  6. Carrots are also a great addition. If you are using a baby carrot variety, you can plant rows with 3 cm space between.

Indoor Garden Soil

You should not consider using outdoor "dirt" as soil for your garden. The "dirt" is also quite dense and will ultimately lead to a lack of proper aeration and insufficient drainage. A good mix is 25% sand, 25% vermiculite, 25% peat moss, and 25% perlite. Be sure that mix is sterile to avoid any pathogens that might bring diseases to the plants.


A standard potting mix from the home and garden center is typically fine to use. However, I would recommend adding some worm casting and/or compost to the mix as well to give it a head start with the nutrients. The vegetables will eventually use all the original nutrients in the soil and additional nutrients will need to be added regularly. This can be done through adding some compost to the top, but often, will require some additional fertilizer.
What kind of container should be used?

Pot type is subject to your own preference and will need to be chosen based on the location(s) you plan to keep your garden. The material of the pot itself is not important, however sufficient drainage is critical! Anticipate that you will need to switch the plant to larger pots eventually so keep an eye out for roots in the drainage holes. Pots that are too large for the plant will not use the water adequately which may lead to root rot, so ensure that the pot you are growing it in is reasonable for the current size of the plant. Old yogurt containers with holes in the bottom act as a good segway for smaller plants which can then be transferred to a 5 or 6 inch pot when ready.

To repot, get your larger pot ready with some additional soil with space to add your plant. Pull the plant, soil and all from the smaller container by flipping the plant and container upside down and sliding it apart. Break the soil up with your hand, fit into the new pot, and add soil around and on top of the rooted area. Be sure not to add too much above the planted area, we want to allow the roots room to grow and they will grow down and out, not up.

Depending on the plant, you will want to consider what type of containers you are using. Carrots and beets will require depths relative to how large you want them to be before you harvest. I find 4-6" is sufficient for these and I like to use trough like containers. Larger plants such as tomatoes and peppers need larger pots to support the taller growing, heavier plants. Ensure to transplant when necessary to let those roots have some space to grow. The smaller leaf veggies like lettuce, cabbage and spinach do not need much depth as they are typically harvested young. A 3-4" pot or planter is all that is really needed to maintain them. No matter which container is used, ensure it is sterile and has proper drainage! (this can't be stressed enough)

Continued on next post...

Sunday, August 9, 2009

Starting an Indoor Garden

Getting started with an indoor garden takes a bit of planning. If you have never had an indoor garden before, it is probably the best idea to choose plants that are easiest to work with. As you become more experienced, it is easy to move into more difficult plants and alternative grow methods like hydroponics.

Sunlight and Water:

The first thing that should be determined is the location of where you can provide enough light for your indoor garden. For herbs, you should have at least 5 hours of sunlight. Depending on the plant, more sunlight would be required. We will talk about that in a future post. Generally, a south facing window would be suffice for most climates. However, in northern climates, winter hours may need to be supplemented with artificial lighting.

Most herbs like to have lots of water, however, they do not like to be saturated and proper drainage is critical. More plants die from too much water than under watering. In fact, it is good to be a bit hard on your herbs to maximize their flavor potentials! Once they are growing well, letting the soil grow completely dry for a while will not cause too much strain on them. All in all, herbs are typically resilient and are pretty hard to kill.

The soil should have a high content of sand and/or vermiculite to ensure good drainage for the plant. Since sand and vermiculite tend not to hold much nutrients themselves, fertilizer is typically required. Even in a premixed potting soil, the nutrients will eventually dissipate and will require some added nutrients. At home and garden centers, you should be able to find fertilizer for edible plants. Once a month, it will be necessary to add these nutrients to your plants.

If you are new to indoor gardening, using individual pots for each plant is the best starting point. 6" pots are a good size for most people as this provides a sufficient amount of harvest potential while still allowing the herb to recover and regrow for additional harvesting at a later time.

Best Herbs for the Indoor Garden:


Here is a list of herbs that tend to do well in an indoor herb garden:
  1. Oregano takes care to get started from seeds, however, once going putting them in a south facing window will help them continue to thrive.
  2. Basil starts well from seeds. Placing in a south window is best as it likes a lot of sun and warmth.
  3. Chervil starts well from seeds and also grows well under lower lighting conditions.
  4. Chives love lots of light and are an excellent indoor herb.
  5. Bay Leaves are perennials that require lots of air circulation to thrive. You can put it in an east or west facing window by itself for optimum yield.
  6. Parsley likes full sun, but is capable of growing either on east or west windows as well. More sunlight equals better yields.
  7. Rosemary is a personal favorite of mine and can be started easily from a cutting in an existing plant. Keep the cutting in a moist paper towel until it roots, and plant. South facing windows are best.
  8. Sage grows well in dry environments and is a sun lover. Keep in the south facing windows for best results.
  9. Thyme is a versatile plant which will do well in lower light conditions, but prefers south facing windows to optimize its yield.
This should be enough to get you started on the joys of having fresh herbs grown right from your home! Later we will talk about harvesting, alternative growing methods, and vegetable growing.

Have fun!