Posts published on May 2010

Basic Kit to Grow Indoors


indoor-garden2Basic Kit to Grow Indoors

You don`t need a lot to start growing great flowering plants.  Apart from the plants the lamp is the most important thing. There are two types used for growing light hungry plants. Metal Halide (MH) or High Pressure Sodium (HPS). HPS lamps used with horizontal reflectors (shades) produce the most usable light per watt of electricity and flowering plants love the light they produce. A 600 watt HPS lamp will light about 1 square meter of growing space. All the kit listed below can be found at a San Diego Hydroponics & Organics.

Basic Kit to Grow in Pots

1. High Pressure Sodium Lamp (600 watt is the most efficient but a 400 watt may suit a smaller space).

2. Fan running 24 hours a day if possible and oscillating.

3. Pots, trays and chosen growing medium. 50% potting compost 50% Perlite is a basic mix. Raise the pots in the trays with bricks or bits of wood so they don`t sit in a puddle when watered.

4. 24 hour timer to control light periods. This should be used with a high power switch known as a relay switch as grow lamps can easily burn out regular timers used on their own.

5. A pH tester to test water and nutrient feed solutions.

6. pH adjuster such as phosphoric acid to adjust water and feed solution to around pH 6.0 – 7.0.

7. Nutrients, ones aimed at growing the plant you want to cultivate are best.

8. White Paint for a grow area or we recommend a grow tent.

9. A measuring bucket, eye dropper and measuring shot glass jug.

For more indoor,outdoor, and hydroponics information, please visit San Diego Hydroponics & Organics website.

Watering Plants


dirt_soil_lgHow much water should I give my plant?

Over-watering is the most common cause of death in indoor plants. Over-watering kills the plant by rotting the roots and preventing the plant from absorbing much needed oxygen.

There is no easy answer to “how much water should I give my plant?” This amount could depend on the type of plant you have, where it is located, how old the plant is and the type and size of the pot. Even soil conditions come into play as some soil holds more water than others.

Plants with large or thin leaves usually need water more often than succulent plants.

During dormant conditions, or just after heavy flowering or growth periods, plants require watering less often.

Water your plant whenever it is necessary. The best way to know when it is necessary is to touch the soil. If the plant soil is dry to the touch, does the plant need water?  If it sounds hollow, watering is needed.

How to water a plant

When the soil is dry, water the plant thoroughly. In fact, water the plant until the water comes out of the bottom of the planter. This will guarantee that the bottom roots in the planter have gotten water as well. However, don’t let the pot sit in the water on the saucer. Empty the saucer once it is done draining.

Make sure the water temperature is between 62 and 72 degrees F. You don’t want to shock the plant.

For more indoor,outdoor, and hydroponics information, please visit San Diego Hydroponics & Organics website.

Summer Heat


resizer.111The least expensive way of reducing the heat in the grow room is to vent out the heat and replace it with cooler air.

Sounds simple right? Well it is, but what most beginners forget is that you can’t blow the hot air out without a way for the cool air to get in to replace it. The best way to setup a venting system like this is to mount one exhaust blower on the inside of the grow room up high to blow the heat out, and another blower on the outside mounted down low blowing cool air in. Hot air rises, cool air settles.

Exhaust blowers are rated or sized in Cubic Feet per Minute (CFM) of air, like “265 CFM”.

This is the amount of air the blower will move in one minute without any restrictions on the intake or exhaust. If a blower is rated at 265 CFM but it’s connected to a 25 foot long tube like a dryer hose, it’s not going to move 265 CFM because of the resistance in the hose. Aluminum tubing with smooth inside walls creates less resistance and the blower runs more efficient. So what size blower should you get? Well it just depends on how fast you need to exchange the air. If your grow room is 6 feet wide, 6 feet long and has an 8 foot ceiling you have 288 cubic feet of air in the room (6x6x8=288). So if your blower is rated at 265 CFM, and it has no restrictions on the intake or exhaust side, it should take about a minute to replace all the air. Of course if the air your replacing it with is already hot, it doesn’t do much too cool the grow room. So it’s best to draw cool air from outside.

The exhaust blower can be turned on with a thermostat so it only runs if the temperature gets too high.

The thermostats plug into the wall and have an outlet for the blower. When you set the temperature at, let’s say 80 degrees, the blower will turn on at 80 degrees. It will stay on until the temperature drops to 80 minus the differential. The differential is the difference between the turn on point and the turn off point. It’s usually about 4 degrees. This means that if the thermostat is set at 80, the blower will turn on at 80 degrees and turn off at 76 degrees. This gives the blower some working time. If the thermostat had no differential the blower would turn off as soon as it turns on, then off, then on, etc., not very efficient.

Sometimes the air coming in is just too hot and can’t cool the room.

When this is the case the blower can be run on the same timer as the grow light, or another timer set to go on at the same time. This is not really solving the problem, just a cheap fix. The problem is the air coming in is too hot, so why not cool it. An air conditioner can be used for the supply air and a blower can blow out the heat.

An alternative to moving all the air out is to capture the heated air and vent it.

This can be done with an air cooled grow light. The advantage with this setup is that you’re using less energy to move the heat out. The volume of air in the reflector might be 3 cubic feet and you can vent it out in a few seconds. It doesn’t matter if it’s hotter, just how much of it you have to move. Venting a 288 cubic foot grow room that’s 95 degrees takes a lot longer than venting a 3 cubic foot reflector that’s 150 degrees.

Another advantage with an air cooled system is when you’re using a CO2 system too. The CO2 doesn’t get blown out when the blowers turn on. The air in the air cooled system is a separate environment from the grow room. Your CO2 cost will be lower since it’s not being wasted.

For more indoor,outdoor, and hydroponics information, please visit San Diego Hydroponics & Organics website.

Carbon Dioxide (CO2) Explained

Carbon Dioxide Molecule
Carbon Dioxide Molecule

Many gardeners, indoor or greenhouse don’t utilize a tool well used in commercial agriculture. We humans exhale the very gas vital to a living plant’s existence; of course the opposite being true that plants output oxygen for living people to breath. That being said, have you ever heard of talking to your plants? With each breath exhaled or whispered over a plant’s leaves CO2 wraps around their foliage ready for up take.

So just how does one supply their garden environment with boosted levels of CO2?

First lets discuss a little about CO2. PPM stands for parts per million and is the scale used for measuring CO2. In ambient nature CO2 exists at about 350 PPMs, however, in an ideal garden or greenhouse plants thrive best with 1500 PPMs. CO2 is also only useful during the photoperiod of growing and should be shut off at sun down or lights off. Because CO2 is heavier then air the output source or CO2 emitter must sit higher then the plant canopy in any garden.

In my ventures into the gardening world I have heard many growers talk of using dry ice as a CO2 source in their garden. It is true that dry ice produces CO2, however, the amount put off in addition to the inconsistencies experienced with dry ice leads me to recommend leaving this method for your friends to experiment with. For those wishing to avoid the sizable investment into a complete CO2 system, Supernatural nutrient company presents Excello Fizz, the CO2 puck! This little guy is perfect for boosting ambient CO2 levels in small gardens 6x6x8 or smaller. Simply add water to a small bowl placed as high as possible in the room and the puck slowly dissolves over the day into a viable source of CO2. Remember: because CO2 is heavier than air, it’s source whether an Excello Fizz puck or hose emitter must always be placed above your canopy of plants.

The bottle and tank system utilizes liquid gas compressed into a bottle hooked to a regulator that controls the output via the solenoid and flow valve.

The solenoid is attached to a power cord that triggers the release or retaining effect of the regulator. The flow valve controls how much gas is released from the bottle after the solenoid is powered open. The instruction manual offers a few calculations on how many cubic feet your room is, and its corresponding rate to set the flow valve to. The power cord for the regulator is plugged into a timer that controls how often the regulator emits CO2 into your garden. If your garden system operates with a 24-hour exhaust fan some re-engineering to limit the need of that fan must occur. CO2 is useless and expensive if constantly sucked from the garden atmosphere. Using an air conditioner, air or water cooled light reflectors to combat heating issues is advised to decrease fan usage.

For those wishing to avoid refilling CO2 bottles the propane or natural gas burner is advised.

Both units can be hooked into an existing gas supply within your home or branched off to the outside green house. A CO2 burner hangs 18 inches off your ceiling (18 inches of clearance must be maintained on all sides of unit due to open flame) and has a pilot light. Hooked up to a digital reader and controller the CO2 generator releases gas that is ignited via the pilot light and burns off of 1 to 8 burners. The burnt natural gas or propane results in CO2 boosting to 1500 PPMs before the reader/controller shuts the gas supply to the generator off. Using a CO2 generator increases temperature, however, it is ideal for gardens larger then 8×8 requiring massive amounts of CO2 in a quick manor. With proper temperature control generators are great for small gardens, as they require no tanks to refill if plumbed off an existing gas main. Propane generators can also operate off BBQ style propane tanks.

A variety of different meters are available to gardeners. The CO2 control wizard is a plastic syringe growers fill with ambient air from their garden and then blow through a glass rod indicating with a purple mark how many PPMs of their garden air is CO2. This unit is an inexpensive method for gaining insight to the garden climate or testing the accuracy of digital meters. The PPM-3 manufactured by CAP both reads the CO2 levels by “breathing” the garden environment and controls output from a regulator or generator. The PPM-3 boosts CO2 up to a desired level and shuts either regulator or generator off until PPMs again fall below set limit. CAP also makes a unit called the FUZZY LOGIC, which activates the generator or regulator as PPMs of CO2 begin to drop, maintaining a more consistent level of CO2 during the photoperiod. Digital controllers such as the PPM-3 and FUZZY LOGIC take the guessing game out of gardening with Co2 ensuring that your plants live in the best environment possible.

Grow Room Feng Shui


Grow_room_1Designing your space is an integral part of creating an indoor grow room.

A good place to start your planning is at the top and bottom of your room. Airflow and circulation are essential considerations for the design of your grow room, as everything from temperature to humidity to plant respiration depends on your exhaust and intake systems.

Start by plotting out where your system will stand; usually this is in the center of the room, but depending on the doors or windows, it can vary. Then mark the floor with tape to get a visual on your layout. Next, think about light placement over your garden. This is particularly important for your room design if you plan to air-cool your lighting set-up.

Air-cooling your lights is a great way to control the atmosphere and temperature.

But be forewarned: Using an advanced strategy like this can create twice as much work in terms of building your room. Because using an air-cooled lighting system requires an exhaust/intake system that is separate from your general room-exhaust/intake system (used for ventilation and air circulation), this means twice as many fans, holes and duct work.

The bonus here, however, is that with a separate cooling system for your lights, you can safely use a CO2 system in your garden without worrying that the gas will get sucked out when your room exhausts. Because you’re air-cooling your lights, your room’s fans should vent the air much less frequently, since garden temperatures will be lower.

Recirculating the air in your garden serves multiple purposes.

Besides blowing fresh air (with more CO2) past your leaves, grow room intake and exhaust fans help keep humidity down and prevent heat pockets from building up over your garden.

Heat build-up is a big problem in poorly ventilated grow rooms.

When all of this is taken into consideration, a simple conclusion is that every grow room should have an intake fan low in the room to bring in cool air and an exhaust fan near the ceiling to expel hot air. Some growers may even use ducting to extend the fan’s range or to exhaust a specific area, such as directly above the lamps. Keep in mind that in larger spaces, ducting from lights, vents and fans will need to be suspended throughout the area, and this is no easy endeavor.

Also remember that if you decide to utilize an air-cooled light, you will need to find two additional points—one to intake cooler air to run over the bulb, and one to exhaust the lamp’s heat.

However, depending on your room’s size, it may not be necessary to use outside air to cool your bulb. In some smaller set-ups, it can be efficient enough to simply suck hot air right off your lamp by attaching some ducting to a flange on the hood of your light and a fan at the other end. For beginners, this can be a great technique to use, since it would allow the same fan to serve as your room’s overall exhaust fan. In a smaller room, this simple system could keep temps low enough to effectively kill two birds with one fan.

For more indoor,outdoor, and hydroponics information, please visit San Diego Hydroponics & Organics website.

Grow Year Round



Do you love fresh fruits and vegetables?

Why not consider an indoor grow box or closet. Why pay all the high prices at the local grocery store when you can grow your own amazing veggies at home. Most people think that hydroponics is a relatively new concept, but in fact the concept has been around since 1627.

So what’s an indoor grow closet?

It’s a device used for growing plants indoors and they are usually designed to be self-contained and small enough to fit in a closet or in a small corner of the basement. They are automated systems that keep a flow of water constantly supplying the roots of the plants with a nutrient rich solution. Generally they have a couple of vents, one fresh air vent to bring in air and an exhaust vent to remove stale hot air. Some really high end systems may even have air conditioning to keep running temperatures down as well as help put more CO2 back into the system to boost the plants growth rate. These types of grow boxes are usually used by people who don’t have enough room for an outdoor garden or they live in a small condo and still want to grow their own fresh veggies. Indoor grow closets can be used year around no matter what the weather decides to do, even in the dead of winter you can still grow some sweet fresh tomatoes. A good closet grow box should include a sturdy cabinet type of box, high intensity lighting, ventilation, a hydroponics system, CO2 generator, odor eliminator, and a temperature monitor. These are the essential components needed for your indoor grow cabinet to really work well.

Indoor grow closets can also help you save water, on average they will use 1/20th the water you would use on a regular soil garden.

Outdoor gardens are beautiful and fun to nurture, but they can have an negative effect on the water quality of your local water supply, run off form your garden may contain harmful pesticides and chemicals that could damage the local Eco-system. Another fundamental component of an indoor hydroponic grow closets are the lights. the best lights for growth are Metal Halide for the growth stages and High Pressure Sodium for the growth and flowering stage. The one main drawback to these types of lights is the cost to run them, they draw a lot of power which means higher electricity bills. Some high end indoor grow closets may contain lights mounted on a track with a motor to move the lights back and forth so the plants get the maximum exposure to the lights for greatest growth results.

For more indoor,outdoor, and hydroponics information, please visit San Diego Hydroponics & Organics website.



NASA-Aeroponics_International-lettuce-day12Aeroponics is the process of growing plants in an air or mist environment without the use of soil or an aggregate medium (known as geoponics).

The word “aeroponic” is derived from the Greek meanings of “aero” (air) and “ponos” (labour). Aeroponic culture differs from both conventional hydroponics and in-vitro (plant tissue culture) growing. Unlike hydroponics, which uses water as a growing medium and essential minerals to sustain plant growth, aeroponics is conducted without a growing medium. Because water is used in aeroponics to transmit nutrients, it is sometimes considered a type of hydroponics.


The basic principle of aeroponic growing is to grow plants suspended in a closed or semi-closed environment by spraying the plant’s dangling roots and lower stem with an atomized, nutrient-rich water solution. The leaves and crown, often called the “canopy”, extend above. The roots of the plant are separated by the plant support structure. Many times closed cell foam is compressed around the lower stem and inserted into an opening in the aeroponic chamber, which decreases labor and expense; for larger plants, trellising is used to suspend the weight of vegetation and fruit.

Ideally, the environment is kept free from pests and disease so that the plants may grow healthier and quicker than plants grown in a medium.

However, since most aeroponic environments are not perfectly closed off to the outside, pests and disease may still cause a threat. Controlled environments advance plant development, health, growth, flowering and fruiting for any given plant species.

Due to the sensitivity of root systems aeroponics is often combined with conventional hydroponics which is used as an emergency “crop saver” – backup nutrition and water supply – if the aeroponic apparatus fails.

Ecological advantages

Aeroponic growing is considered to be safe and ecologically friendly for producing natural, healthy plants and crops.

The main ecological advantages of aeroponics are the conservation of water and energy. When compared to hydroponics, aeroponics offers lower water and energy inputs per square meter of growing area.

When used commercially, Aeroponics uses one-tenth of the water otherwise necessary to grow the crop but this can be reduced to as little as one-twentieth.

NASA has funded research and development of new advanced materials to improve aeroponic reliability and maintenance reduction. It also has determined that high pressure hydro-atomized mist of 5-50 micrometres micro-droplets is necessary for long-term aeroponic growing.

For long-term growing, the mist system must have significant pressure to force the mist into the dense root system. Repeatability is the key to aeroponics and includes the hydro-atomized droplet size. Degradation of the spray due to mineralization of mist heads inhibits the delivery of the water nutrient solution, leading to an environmental imbalance in the air culture environment.

The relatively low solution volumes used in aeroponics, coupled with the minimal amount of time that the roots are exposed to the hydro-atomized mist, minimizes root-to-root contact and spread of pathogens between plants.

More control of plant environment

Aeroponics allows more control of the environment around the root zone, as, unlike other plant growth systems, the plant roots are not constantly surrounded by some medium (as, for example, with hydroponics, where the roots are constantly immersed in water).

A variety of different nutrient solutions can be administered to the root zone using aeroponics without needing to flush out any solution or matrix in which the roots had previously been immersed. This elevated level of control would be useful when researching the effect of a varied regimen of nutrient application to the roots of a plant species of interest. In a similar manner, aeroponics allows a greater range of growth conditions than other nutrient delivery systems. The interval and duration of the nutrient spray, for example, can be very finely attuned to the needs of a specific plant species. The aerial tissue can be subjected to a completely different environment from that of the roots.

More user-friendly

The design of an aeroponic system allows ease of working with the plants. This results from the separation of the plants from each other, and the fact that the plants are suspended in air and the roots are not entrapped in any kind of matrix. Consequently, the harvesting of individual plants is quite simple and straightforward. Likewise, removal of any plant that may be infected with some type of pathogen is easily accomplished without risk of uprooting or contaminating nearby plants.

More cost effective

Aeroponic systems are more cost effective than other systems. Because of the reduced volume of solution throughput (discussed above), less water and less nutrients are needed in the system at any given time compared to other nutrient delivery systems. The need for substrates is also eliminated, as is the need for many moving parts, resulting in lowered manufacturing cost and reduced maintenance costs.

Pathogen control and disease prevention

Plants are most susceptible to loss from pathogens during the first 21 days of their life cycle.

The aeroponic technology developed by the PI utilizes a patented plant support structure that separates the plants from one another. In a hydroponic or aggregate-based system, pathogen infections can easily spread throughout the entire system due to the plants’ common source of water or medium. In the ideal aeroponic system pathogens can be reduced and controlled by:

* separating the plants – thus preventing the pathogen from spreading infection from one plant to another.

* applying disinfectants and fungicides to the aerial and root zones individually,

* applying the water/nutrient at intervals that are best suited for plant development and growth,

* allowing the plant to expand without interference of restricting physical barriers,

* reducing the per plant exposure to surfaces where pathogens can linger or proliferate.

Use of seed stocks

With aeroponics, the deleterious effects of seed stocks that are infected with pathogens can be minimized. As discussed above, this is due to the separation of the plants and the lack of shared growth matrix. In addition, due to the enclosed, controlled environment, aeroponics can be an ideal growth system in which to grow seed stocks that are pathogen-free. The enclosing of the growth chamber, in addition to the isolation of the plants from each other discussed above, helps to both prevent initial contamination from pathogens introduced from the external environment and minimize the spread from one plant to others of any pathogens that may exist.

For more indoor,outdoor, and hydroponics information, please visit San Diego Hydroponics & Organics website.

Building a Grow Room


Grow_room_1Building a Grow Room?

Here are some things to consider:


The main requirement here is that there is easy access to the grow room. There should be enough space to allow you to come and go with ease and also be able to take any articles that you may need to move both in and out of the area. The entrance to the room should have a lockable door on it to stop unwanted visitors from accessing your growing area. This is particularly important if you have curious children in the house, because there will be chemicals in the room which could cause harm to them if mishandled.


The provision of fresh clean water to your grow room is of vital importance. However, it is also essential to have a means of removing that water once it is no longer required. Adequate supply and drainage is not difficult to arrange in this modern age. You can use a system of hoses and storage tanks, together with pumps and multi-way valves to direct the water where you need it.

If you are building a new grow room is it in an area where the weight and humidity will cause damage to the fabric of your building? Remember that hydroponics systems often utilise large quantities of water and water is heavy. (250 litres is about a quarter of a ton) It is essential to work out your loadings and then allow a safe margin for error. It is also highly recommended that you use a waterproof membrane to cover your floor area, as any spillages can cause the ceiling below to become unstable and collapse.


Light pollution is also an area to be looked at. All extraneous light must be blocked out if you wish to grow high quality plants. When you are running on a 12 hour cycle the darkness must be complete as any light at all will trigger the growth hormones in your plants to either turn on or off. It can be very damaging to your crops if this is allowed to happen at the wrong times.


The warm stale air will need to be extracted to the outside, another room or the attic and clean fresh air brought in. This is normally achieved by sucking the air out of the growing room using an in line extractor fan and some suitable sized ducting.


The supply of electricity to your grow room should be carried out by a qualified electrician. Ask him to install a separate ring main for this area protected by an RCD circuit breaker. Make sure that he provides more sockets than you think you will need and that they are placed at high level. This will ensure that you always have enough outlets for any additional equipment you may install at a later date. It will also ensure that you are not getting your electrics and any water in close proximity to one another, a recipe for disaster. The extra ring main will see to it that your house is never affected by a problem in the grow room.


Both the daytime and night time temperatures within your growing area are important. The temperature should, where possible be kept even, without either hot spots in the daytime or cold ones at night. It is possible to purchase environmental control systems which will help you achieve the desired results.

For more indoor,outdoor, and hydroponics information, please visit San Diego Hydroponics & Organics website.

What is Mycorrhizae?


RootsMycorrhizae are symbiotic associations that form between the roots of most plant species and fungi.

These symbioses are characterized by bi-directional movement of nutrients where carbon flows to the fungus and inorganic nutrients move to the plant, thereby providing a critical linkage between the plant root and soil. In infertile soils, nutrients taken up by the mycorrhizal fungi can lead to improved plant growth and reproduction.

They promote root development, fight off disease, break down fertilizers, and they can even fight off harmful soil borne microbes and encourage the growth of beneficial microbes.

Plant responses to colonization by mycorrhizal fungi can range from dramatic growth promotion to growth depression. Factors affecting this response include the mycorrhizal dependency of the host crop, the nutrient status of the soil, and the inoculum potential of the mycorrhizal fungi. Management practices such as tillage, crop rotation, and fallowing may adversely affect populations of mycorrhizal fungi in the field. Where native inoculum potential is low or ineffective, inoculation strategies may be helpful. With the current state of technology, inoculation is most feasible for transplanted crops and in areas where soil disturbance has greatly reduced the native inoculum potential.

For more indoor,outdoor, and hydroponics information, please visit San Diego Hydroponics & Organics website.

Why Use Earthworm Castings, Bat Guano & Humic Acid In Soil?



Why do you use earthworm castings, bat guano, and humic acid in soil?

Earthworm castings are teaming with beneficial microbes that help plants thrive.

Scientists have tried to reproduce every nutrient worm castings contain in the laboratory, but they’ve been unable to create a formula that feeds plants as well as that rich, black, worm poop does.  Earthworms – and their castings – help roots access nutrients that are in the soil, and help plants fight off pests and diseases.

Bat guano is naturally high in phosphorus.

Which helps create dazzling color, scent and taste.  It is also packed with beneficial microbes and helps fight off harmful nematode infestations.  Bat guano also helps facilitate the transformation of soil nutrients into a form that is easier for plants to absorb, making it the perfect catalyst for fertilizers and soils.

Humic acid is a natural by-product of organic decomposition.

It contains trace amounts of nutrients and it helps hold other nutrients in the soil where plants can use them.  It can improve the humus content in the soil, hold water in the soil, and generally improve soil health for better seed germination and plant growth.

For more indoor,outdoor, and hydroponics information, please visit San Diego Hydroponics & Organics website.