Urban Hydroponics frequently asked questions
Urban Hydroponics offers all the advice you need to get you growing. We hope our list of cfrequently asked questions is useful. If you have any question please call Urban Hydroponics on 01204 522217 or send us an email: sales@urbanhydroponics.co.uk
What is hydroponics ?
Hydroponics is the science of growing plants without soil. Instead of soil, plants thrive on nutrient solution which contains the minerals that the plants need. So, rather than searching throughout the soil for minerals, your plants are able to get nutrients easily, directly from the nutrient solution. Grow media -- such as gravel, peat, vermiculite Perlite, diatomaceous earth, rockwool or expanded clay aggregates -- is often used to support the plants and their root systems and perhaps to hold moisture around the roots - the growing medium is totally inert.
Almost any kind of plant can be grown hydroponically, and because plants have access to the exact nutrients they need, they respond by growing more rapidly while producing bigger yields. Field tests have shown that hydroponically grown produce is packed with more vitamins and minerals than soil grown, either organic or non-organic. Not only are nutritional values higher, but the flavours and quality are also outstanding. Since plants start out in a disease and pest free medium, little or no pesticides are necessary.
How do I Grow Hydroponically ?
Urban Hydroponics stocks everything you need to get you growing. In order to have your own automated hydroponic system you need several key things; a reservoir to hold nutrient, a pump to circulate the nutrient, and growing trays and pots for the plants to be held in. Hydroponic systems can range in price and sophistication from under a £100 to several thousand. It all depends on the scale at which you intend to grow and the environment you need to produce for your plants. Take a look at our hydroponics systems for some ideas.
What is growing media?
Growing media helps to ensure that plants get the proper ratio of, water and oxygen - both which are critical to healthy plant growth. Growing media also provides support for plant roots and it protects roots from sunlight. Urban Hydroponics stocks many different types of media. Please a look at our grow media section.
What is Ebb and Flow ?
Often these types of systems are called flood and drain. The plants are usually grown in pots with their roots supported by a medium of perlite, Rockwool or expanded clay pebbles (Hydroton.) The pots sit in a plastic tray which in turn sits above a reservoir filled with nutrient solution. The growing tray must be higher than the reservoir because the system relies on gravity to do the work.
A pump in the reservoir is connected to the bottom of the tray. When the pump turns on, the tray fills with water. When the water level reaches a pre-determined height, through the use of the overflow fitting, the water falls back into the reservoir. When the pump turns off, the water runs back down through the pump into the reservoir. Poetry...
Most growers choose to control irrigation with a timer. A typical schedule would involve several short one-hour water cycles per day, but the duration and frequencies of watering cycles varies from one system to another and is dependent on the crop, the plant size and environmental conditions.
Ebb and flow allows for high density planting while providing a well oxygenated root system. The ebb & flow method supplies fresh oxygen to the root system of plants in two ways. First, as the tray is flooded with nutrient solution, carbon dioxide rich air is pushed out from around the root system. When the pump is turned off, the tray is drained and oxygen rich air is drawn down to the roots. This oxygen is then used by the plants until the next cycle begins.
Second, when the nutrient solution drains through the flow, it creates a splash upon impact, adding much additional aeration.
What are Drip Systems ?
Drip systems are the most widely used hydroponic systems in the world. They are commonly used in commercial facilities for growing long term crops like tomatoes and peppers. Drip systems provide plenty of aeration (more than ebb and flow) because plant roots are never totally submerged, but are never allowed to dry out. There is also the additional aeration that occurs from water falling back into the reservoir.
Click here to see how this aeration works. (note that the splashing has been artistically amplified - it doesn't really splash out of the reservoir in that manner.)
Drip systems operate very simply. A pump has tubing connected to it which then branches off to smaller tubes feeding many plants. It works just like a drip irrigation system in your yard. Nutrient solution is dripped onto the base of each plant where it then trickles down through the grow media and into the roots and finally drains into the reservoir where it is reused.
A drip system may be left to run continuously or it may be turned on and off with a timer. A good standard to go by is on for an hour and off for an hour, however we suggest experimenting to see what works best for you and your plants.
What is Nutrient Film Technique (NFT) ?
Nutrient Film Technique systems are some of the most productive available, and they are often the chosen method of commercial growing. Plant roots are grown in a light-tight and shallow channel. Nutrient solution is continuously circulated, flowing over the roots up to 24 hours per day. The name of this growing method was so coined in order to stress that the depth of the liquid flowing past the roots should be very shallow in order to ensure that sufficient oxygen is supplied.
A wide range of vegetables and ornamental crops may be grown in an NFT system. Depending on channel width, NFT is great for plants as diverse as tomatoes and lettuce. When choosing an NFT system, care must be taken to choose the correct trough size. Small 4 inch troughs are fine for most plants, but larger vine crops with extensive root systems could hinder nutrient flow, causing root rot and pathogen growth. Large commercial systems use wider troughs with greater flow capacity.
What is Aeroponics ?
Aeroponics is an exciting improvement on hydroponics that has been shown to greatly increase yields. The growing environment is similar to a misty rainforest with plenty of oxygen and moisture. In Hawaii, orchids are often seen growing freely in the trees due to the level of humidity in the air. Aeroponics strives to create this environment at the root zone.
The roots of the growing plants are suspended in the air, and they are misted by high pressure sprayers. The sprayers break the nutrient into small particles and saturate the roots. The levels of oxygen in the water are kept high by the constant circulation of the water. Aeroponics is beyond the age we're in now-- it's in the space ages. Aeroponic techniques are being investigated by NASA.
Why is good lighting important ?
Urban Hydroponics believes light is the most important factor in any indoor growing environment. It is also the limiting factor in any indoor growing environment. Lighting technology has vastly improved over what it once was and it is continually evolving with new and better technologies. Without good and plentiful light, a plant will not be able to perform photosynthesis, chiefly the main principle by which a plant converts food into energy. Plants are able to use artificial light, so long as it is of the correct growing spectrum & there is plenty of it. See our lighting section for our vast range of lighting solutions.
What are HID grow lights ?
High Intensity Discharge (HID) lights are the main source of light in any serious indoor garden. With the application of an HID light, gardeners are no longer limited by the number of lumens in the growing environment. HID lighting is also the most efficient source of indoor lighting available today. These lamps produce 4-6 times as many lumens/watt compared to any incandescent light of the same wattage and will last much longer. Bulbs range in sized from 100 to 1500 watts.
The main drawbacks to HID lighting systems is that they put out intense heat, which subsequently causes plants to dry out faster, and the fact that they are incapable of providing the entire natural spectrum. HID lights come as close to natural light as human technology can take us, but natural sunlight is still more full and vibrant. There are two types of HID lamps to be aware of, Metal Halides and High Pressure Sodiums.
What are Metal Halides ?
Of the two kind of HID lights, metal halides have the more balanced spectrum. They will bathe plants in light from the bluer end of the spectrum, which indicates to the plant that it's spring and time for growth. Generally speaking, Metal Halide light is used for plants which are encouraged to grow many leaves and become bushy such as lettuce, spinach, cabbage and herbs. They are also excellent for the vegetative stages of growth. They promote tight internodal spacing between branches, and help the plants to develop thick stems and large leaves which will support later fruit and flower growth.
Recent strides in lighting technology have begun to produce metal halide lamps that will reproduce a more balanced spectrum providing more of the orange/red end.
What are Sodium lights ?
High Pressure Sodiums (HPS) lamps reproduce light from the red/orange end of the spectrum, mimicking the colors of the harvest sunset. Plants use this kind of light in reproductive processes, and thus HPS bulbs help your plants to produce more fruits and flowers. At 97-150 lumens per watts, HPS light produce more lumens than a MH, but. exposing flowering plants to only a red spectrum light during the vegetative stage tends to make them stretch, lose their color and start to look downright unnatural.
HPS lights, like their MH counterparts have new bulbs which increase their less intense blue end to their spectrum. With the SunAgro (HPS) or the Hortilux, you can get a 25-30% increase in the blue end of the light spectrum. These lamps will produce more natural compact growth.
Can I use flourescent lights ?
Fluorescent lighting is mainly used to sprout seedlings and to initiate rooting in nascent cuttings (clones). Your average fluorescent bulb produces 2300 lumens, which is not enough to grow your typical tomato plant (requiring 41,000-46,000 lumens). There are specialized, full spectrum high output fluorescents which will vegetate plants at an acceptable growth rate, but the growth will still be slower and less full than an HID light.
There are some very important benefits to using fluorescent lighting. They are energy efficient, relatively inexpensive, and can emit a wide spectrum of light suitable for most plant growth. They also have a very low heat output. These lights excel at seed sprouting and growing very young plants.
How do I calculate energy costs ?
You need to first find out how much watts you will run. Next you must calculate your Kilowatt per hour (KWH), which is located on your last electric bill.
Note: 1 KW= 1000 Watts
Watts of light = Amount of Kilowatts you are running per hour
Example: 2000 Watts = two 1000 watt lights
2000 Watts X 1000 watts/1 kw = 2 kw per hour of use
So now say you are running your lights for 12 hours a day. You then multiply your kwatts per hour by 12 (hours running in the day)
So in our previous example: 2 kwatts/ hour X 12 hours = 24 kilowatts a day
Multiply by days in a month: 24 Kwatts per day X 30 days = 720 Kw per month
Now you take that and multiply it by the rate charged by the electric company.
What is pH?
The pH value of a nutrient solution is a measure of the acidity or alkalinity of a solution. A basic, neutral solution is numerically equal to 7. The solution gets more acidic as the numbers decrease and more alkaline as the numbers increase. The ph scale ranges from 0 pH (very acidic) to 14 pH (highly alkaline). Pure water has a pH of 7, indicating that it is neither alkaline nor acidic, but neutral.
What is EC ?
EC stands for Electrical Conductivity and is measured in mS/cm or miliSiemens per centimeter. An EC meter measures an electrical current in the solution and reads the conductivity produced from the motion of the mineral ions. Low conductivity means low nutrient concentration, often resulting in nutritional deficiencies and slow plant growth. High conductivity means more food for your plants. But be careful of not to get over zealous with the concentration of your nutrient solution; very high conductivity can burn or kill your plants.
Why do growers add Carbon Dioxide to their gardens ?
Carbon Dioxide, known as CO2 is a much needed resource for your plants' development and overall growth. Plants use CO2 in their respiratory cycle, much like we depend on oxygen. Plants can absorb much more CO2 than that which is available at natural atmospheric pressure levels. In most outdoor environments, CO2 is available at 450 parts per million (ppm). Most plants can use anywhere from 1300 to 1600 ppm. This is roughly up to 4X the amount that is available outside. If you give your plants these elevated levels of CO2, you will immediately notice a vast increase in plant growth, development and fruit/production.
What is cloning ?
Cloning is a form of plant propagation that has been around for a very long time. It's basically taking a growing portion of a plant - a stem with some leaves attached, and helping it to become a brand new plant that is genetically identical to the plant from which the clone was taken. This is often easy to do because plants often clone themselves in nature. It's called asexual reproducation. The methods currently used today include taking cuttings, layering, division, grafting, budding and tissue culture. Gardeners often trade cuttings and divisions as a way of sharing plants with their friends.
What are cuttings ?
A stem cutting is a terminal growing point on a plant. It is 4 to 6 inches long and is cut off at a node. A node is the point on a stem where a leaf is attached. The bottom leaves are removed from the nodes and the lower end is inserted into the rooting medium. Some plants are excellent material for cuttings; others never survive. Both woody and herbaceous plants may be used for cutting materials.
How do I germinate seeds ?
Urban Hydroponics recommends the below methods for germinating seeds depending on the variety of plant you wish to grow.
1. Put some moist tissue on a plate. Put the seeds on top of them and cover the seeds again with moist tissue. Cover the plate with another upturned plate, so that the seeds are in darkness and the environment remains moist. Put the covered seeds in a warm place (21°C). Check the seeds every day, spray the tissues with water if necessary to keep them moist but not soaked. Very carefully transplant (preferably with tweezers) the seeds to a planting medium as soon as they open and the tip of the root becomes visible.
2. Place the seeds under the surface in the planting medium at approximately the depth of the seed. Regularly spray the planting medium with water, but make sure that the soil or rockwool does not become too wet. The seedling uses the spare food present in the seed for growing so nutrient is unnecessary at this stage. Air is very important for its metabolism. So make sure that the soil remains sufficiently airy. One of the characteristics of rockwool is that it retains plenty of air. Make sure that the rockwool is not standing in water and that any excess water is able to drain away properly. Properly used, Rockwool is a fine germination environment for the seeds. Peat tablets are ideal for starting seeds that will grow in soil. Keep the seeds warm (21°C) and moist, i.e. in a propagator. Remove the cover as soon as the seedlings sprout above the medium.
Help, I've got young seedlings, what do I do ?
Young plants are very delicate. Therefore you should not place them in direct sunlight or under a 400 w propagation lamp. This might cause burning. Provide young plants with nutrient water with a low ec value (1.2) and add growth boost to strengthen the root system. When the seedlings have grown 2 or 3 sets of serrated leaves they are ready to transplant.
Finally.......
Hope this section is of benefit to you. If you require any further advice please contact us direct. Like Urban Hydroponics this section will continue grow, if you have any tips or advice please mail us at sales@urbanhydroponics.co.uk
Happy Growing !!!!!! Urban Hydroponics :)