Friday, May 31, 2013
big marijuana
harvesting and potency
Potency is measured by the percentage by weight of THC in a dried sample of the uppermost leaves or growing shoots until flowers appear. It shows that generally potency increases as the plant develops. Cues such as phyllotaxy changes and rate of growth are helpful indicator to changes in development and the chronological age of the plant has little significance.
The development of the cannabinoids, resin glands, and, in practical terms, the potency in the living plant is not clearly understood. It is believed for the most part, potency does not increase steadily throughout the entire plant. Rather, each plant part reaches a point of maximum potency as it individually develops. A leaf that is formed when the plant is four weeks old does not increase in potency during the rest of the season. To say that potency is increasing means that the leaves that are now forming are more potent than those previously formed.
It is believed that cannabinoid formation is very fast as each plant part forms. Once matured (for example, when a leaf is fully expanded), cannabinoids are decomposing. This is one reason why the potency can decrease as well as increase during growth, especially late in the season, after the flowers have formed.
Leaves
The potency of each new set of leaves is higher than the last pair until a plateau is reached, usually during the middle of vegetative growth. Thereafter potency of new leaves stays about the same as in those preceding. Often there is a noticeable decline in potency just prior to flowering. Leaves that form during flowering are usually more potent than those formed during the vegetative plateau. Leaves that form after the bloom are less potent.
Of course, not all varieties or individual plants will follow this rhythm. Faster-developing plants may reach the plateau sooner, and slower plants later. Potency of plants that have a longer life cycle may stay at the vegetative plateau for several months. Some plants do not seem to experience any drop in potency before flowering. Potency of these plants continues to increase gradually after the initial quick increase during early vegetative growth.
Whenever you harvest green leaves during growth, you should always take the uppermost leaves, since these are the most potent. Also, the smaller leaves that form on the branches are more potent than the large leaves on the main stem. These large stem leaves (fan, shade, or sun leaves) are often the first leaves that growers pick. But these are the least potent of all leaves, and the may not get you high at all. As long as these leaves are healthy and green, let them stay on the plant for the plant's growth. Many growers simply use these leaves for mulch or compost as they die.
Don't think that you should harvest each leaf as soon as it appears; this procedure would seriously affect normal growth and result in a small harvest of buds. The potency of individual leaves does not increase during the course of the season, but the decrease in potency is not great. Some of the loss in potency may even be made up for by the loss in tissue weight that a leaf experiences as it dies. Many growers prefer to harvest leaves during growth only after they lose colour, preferring the taste of the smoke to that of green leaves.
Male Plants
Male plants usually do not have the dramatic increase in potency during flowering that the females do. Male flowers take about two weeks to mature, from the time they are first visible as tiny knob-like buds. New flowers continue to appear for several weeks.
When male flowers open and are about to release pollen, they reach their maximum potency. Since all flowers do not mature at the same time, for maximum potency the plants should be harvested after the first few flowers have opened.
Male flowers actually make up little of the total weight of the harvest, and few new leaves form once flowering begins. There is no significant loss in either potency or yield if the male is harvested before its flowers open. Once male flowers appear, there is little change in their potency. Also, once the flowers do open and release pollen, they shortly fall from the plant and are lost to the harvest.
Males should therefore be harvested before any flowers open unless you want the females to produce seeds. In a small garden, male flower clusters can be individually harvested as they mature. Most growers treat male flowers more as a novelty. Potency of male flowers is quite variable, and seldom are they as good as the female flowers. To remove male plants, cut them near the base of the stem. Don't rip them up by the roots if they are near females that will be left to grow.
Male plants normally begin to lose their vigour after the initial bloom. When the weather is mild, or the plants are indoors, they can be encouraged to bloom a second and sometimes a third time before they finally die.
Harvesting Female Buds
The decision of when to harvest females can be simplified by understanding that you want to pick the buds after they have developed fully, but before degradation processes begin to lower potency. There are two criteria you can use to tell when the plants have reached full bloom. The first is recognising the rhythm, with which the plants are blooming. A second is the condition of the flowers as judged by the health of the stigmas and the colour of the resin.
Sinsemilla
Since sinsemilla flowers are not pollinated, the flowering period may last for many weeks. The most common rhythm for sinsemilla is that plants go through a stage of rapid bud formation, and the plants do indeed bloom. This bloom often lasts four to five weeks. The bloom ends when the rate at which new flowers form noticeably declines. At his time you should be able to sense that the bloom is completed. Buds are at their peak potency about one week after flower formation slows. This is the time to harvest. True, the plant may continue to grow slowly, but the main harvest is ready and should be taken.
With sinsemilla, some marijuana varieties have an extended bloom that may last more than two months. With this rhythm, the rate at which the buds form is drawn out, and progresses at a slower but steadier pace. The point at which the bloom is essentially over may not be as obvious as in the first case. Here, use the condition of the buds to make your decision. Stigmas wither first at the base of the buds (older flowers). Those stigmas at the top of the buds (younger) will still be white and healthy, although their tips are often brown. Harvest the plants when about half the stigmas in the buds have withered. The coating of resin glands should still be clear or white, with only a few golden or browned gland heads.
A third type of flowering rhythm is sometimes seen on plants from Thai seed. Flower buds bloom and ripen at different times. These plants also have an extended flowering stage that can last for over two months. You may choose to harvest individual buds, colas, or branches as they ripen.
Seeds
If your primary interest is seeds, the plant should be harvested after the seeds have developed their mature colour. Mature seeds can be seen splitting their sheaths or bracts. When enough seeds have ripened, the plants should be harvested. If the plants are left in the ground and die, many of the seeds will fall from the plant.
For most growers, potency will be of primary interest, seeds only a secondary. With seeded marijuana, flowering is initially rapid until the plant is well-pollinated. If pollination occurs early in flowering, the plants often bloom for another week or two. Generally, you want the plants to flower for at least four weeks before picking, and usually longer, about six to seven weeks.
With seeded marijuana, the bloom is of shorter duration than with sinsemilla. Once growth slows, wait another two to three weeks before harvesting. All the seeds may not be matured, particularly at the top of the bud. But potency of the buds should be about maximum at this time.
Weather
Because of such variables as variety and growing conditions, there can be so much variation in the ripening process that no one criterion for judging when maximum potency is reached will be reliable for all cases.
Warm, sunny weather encourages rapid flowering and a long period of receptivity by the stigmas. Cool, rainy weather can wither the stigmas and dampen the vigour of the bloom.
If brief frost or long, cool rain has withered the stigmas, use the plants' growth as a guideline, because ultimately this is the most important criterion. You want the buds to reach a mature size, and to ripen for about another week. You do not want the buds to be left on the plant longer than necessary.
Ideally, harvesting should follow a period of warm, sunny weather. In northern and mountainous parts of the country, many tropical varieties will note flower until late in the season, when the weather has cooled and night-time frosts are threatening. Most mature plant can withstand mild frosts and continue to grow well if daytime temperatures are mild. In this case, let the plants mature, since formation of the buds is more important than the weather in determining potency. Watch the plants carefully, and harvest when the buds reach mature size. Marijuana killed by frost may smoke harshly, but potency does not seem affected. Well-formed buds should be picked if heavy rains are expected. Cannabinoids are not water-soluble, but gland heads will be washed away.
Barring a catastrophe, such as a long frost, death to Cannabis is usually not sudden. The plants will continue to grow, and may infact rejuvenate the next year if the stalks are left in the ground. But after the main bloom, the growth that follows is usually much less vigorous and sometimes forms abnormally. Leaves at this time are simplified, and have one blade. Later leaves are smaller, and tend to have entire margins (no serrations). Sometimes they are twisted or misshaped, as are the flowers that form along with them. This slow growth that follows the initial bloom will contribute little to the weight of the harvest. Additionally, this post-bloom growth is much less potent than the original bloom. Resin glands on these plant parts are feeble and poorly developed. When this abnormal growth forms, the time for harvesting is past.
When a plant seems to persist in growing, and you are not sure bloom is past, the best procedure to follow is to try for a double harvest.
Double Harvests
Most marijuana plants take at least five months to reach maturity. Once the plant has reached maturity, it is forming its most potent marijuana, and should not be cut down completely. You can often induce the females to flower a second (and sometimes a third) time, especially if the plants are indoors or if the weather is expected to stay mild for several more weeks.
To encourage a second bloom, first take the bulk of the harvest: all but the smallest buds, and most of the leaf. Some green leaves should be left on the plant to maintain the plant's growth. After harvesting, give the plants a thorough watering, and water with a soluble, complete fertiliser that provides a good supply of both N and P. This will encourage new growth and continued flowering.
Indoors, the best procedure is to treat the plants like a hedge. Cut all the plants back to equal heights, about two to three feet tall. Remove most of the grass, but again leave a few green leaves on the plant. Don't remove lower branches even if they are leafless, since these will sprout again. Lower the light system to the tops of the plants, and maintain the daily cycle at about 12 hours. The second crop of buds will be ready for harvest in four to eight weeks. With this system, the plants appear like dense hedges of buds. If the second crop of buds forms quickly, you should try for a third crop. Continue to fertilise the plants regularly, and watch for signs of magnesium deficiencies, which often show up when the plants have been growing for an extended time.
Double and triple harvests are one of the benefits of indoor growing. Although plants are relatively small indoors, the original harvest of buds can be triples in the next four months.
You also have the option if a perpetual operation indoors. If you are skilled you can produce up to 13 harvests in one year.
Potency and Decomposition
It is said that when buds are picked too late, the potency may decline because of decomposition of the cannabinoids, especially THC.
Light rapidly decomposes THC into unknown products (possibly polymers (122,164)). Light also converts CBD to CBS and CBC to CBL. Air (oxygen) slowly converts THC to the less active CBN. Conversion to CBN is hastened by higher temperatures.
Degradative processes do not occur as quickly in the living plant as when the cannabinoids are purified or in solution. Resin glands seem to function well in storing the cannabinoids in dried plant material. However, Temperature would be higher, and light stronger, under full sunlight.
Studies with fresh plant material usually show negligible CBN content in fresh marijuana from immature plants. When mature buds are tested, their CBN content is generally equal to at least five percent of their THC content. When growing temperatures are higher, such as in the tropics, CBN content can account for more than 20 percent of the original THC. Even if we assume a low figure, such as five percent conversion of THC to CBN, there is actually a much greater decline in THC content because of the simultaneous degradation of THC by light.
When the slow rate at which THC oxidises to CBN is considered, five percent decomposition in a period of less than two months represents considerable exposure of the THC to air, and most of this exposure occurs in the last critical weeks when the resin glands begin to degenerate.
Stalked glands that cover the female flower bracts sometimes rupture or secrete cannabinoids through pores in the glands head. Secretion is not a continuous flow, but more of an emptying of the glands' contents. At this time, gland heads may dehisce. Also, because of their abundance and raised positions, resin glands on the female bracts are exposed to strong sunlight and possible physical damage. These conditions may explain the significant decline in potency of buds that are overripe.
Leaves are also affected by decomposition of the cannabinoids, but not as quickly or seriously as the buds, probably because the resin glands on the leaves are most numerous on the undersurface, where they are somewhat protected from light. These glands rarely rupture or secrete cannabinoids. Often they are intact, clear, and apparently unchanged for many weeks on the living plant.
As the plates show, one can, with the naked eye, see the glands change colour, from colourless or white to golden, and then to reddish or brown. THC is colourless. If the colour changes of the resin do indicate decomposition of THC, then decomposition in the stalked glands that cover the buds can be considerable.
Buds have been smoked that seemed to lose about half their potency when left on the plant for an additional three weeks. Colour changes are after the fact. If many of the glands are beginning to brown, the flowers should be harvested.
Timing the Harvest
Many growers will disagree on when the best time is to harvest the buds (female plants). When the plants are left in the ground, and are alive but past the main bloom, the resinous qualities of the plant may become more apparent. The bracts and tiny leaves may swell in size, and the leaves feel thicker. The coating of resin glands will change colour. Leaves often yellow and fall form the plant. Much of the green colour in the flowering buds may also be lost. Harvests of these buds more closely resembles commercial Colombian grass than typical homegrown. The resin content of the dried buds may be higher, and the grass will smoke more harshly than if the buds were younger when picked. You may prefer these qualities in your grass, and some growers insist this grass is stonier. The herb will give you the highest high when it is picked as described previously. Smoking is a personal experience, and you should try different approaches and come to your own conclusions.
The first time you grow marijuana is largely a learning experience. Most growers can't wait to start their second crop, because they are certain that they'll improve on both the quantity and the quality of their crop, and this is usually true. The wise grower will not put all his proverbial eggs in one basket. It is a good idea to monitor potency by taking samples every few days when harvest time is drawing near, just as such monitoring is for deciding when to harvest growing shoots during vegetative growth.
In any garden, some of the plants will mature sooner than others. Use the plant(s) that is earliest to mature to decide at what point in its development the plant reaches maximum potency. This finding then serves as a guide for harvesting the rest of the plants.
Try to use buds from approximately the same position on the plant each time you sample. Take only enough to make a joint or two. The more you standardise your testing (and this includes your smoking evaluation), the more accurate your results may be.
Final Harvesting
The time of harvest is a time of joy. It is also a time for caution. Unless the safety of your garden is assured, you will want to harvest quickly, quietly and as efficiently as possible. Ideally, each plant is harvested as it matures, but some of you will have to harvest all at once.
It is best to take cardboard boxes or large, sturdy bags to carry the harvest. You want to harvest the plants with as little crushing or damage to the flowers as possible.
Bring a strong knife, heavy shears, or clippers for cutting the stalks. The quickest way to harvest is to cut each plant at its base. Once the plants are on the ground, cut the stalks into manageable lengths for boxing or bagging. Separate large branches as needed for packing.
Indoor gardens have more flexibility and do not need to rush as much. You are able to harvest them as they mature and get them into manageable sizes at the cut.
The bagged or boxed material should be moved to the curing or drying area as soon as possible. If you let the plants sit in the trunk of a car or in plastic bags, they will start to ferment and small in less than a day.
Thursday, May 30, 2013
start at the beginning...
Wednesday, May 29, 2013
bubba blast
Tuesday, May 28, 2013
h2oooooohhhh!
blast off!
Houston, we have a problem....
Monday, May 13, 2013
a touch of Co2
heat
Before getting started it is highly recommended that every indoor garden has a max/min thermometer. This product allows the gardener to see exactly the fluctuations in temperature within their garden. Without this useful tool there is no accurate way of knowing the different temperatures between daytime (lights on) and nighttime (lights off). The difference between the two temperatures is very important to plant growth. Anymore than a 10F-15F difference between daytime and nighttime temperatures and you risk shocking and stressing the plants. In general the optimal daytime temperature for plant growth is between 70F -75F. Drift too far above this range or too far below and growth can be severely affected. Daytime temperatures exceeding 90F or under 62F will stunt a plant's growth. If the temperature drifts higher than 95F the plant’s enzyme production will drop off and the plant will begin shutting down. At temperatures that high photosynthesis shuts down due to the stomata in the leaves closing to conserve water. At normal temperatures the stomata will be open, taking in CO2 and sweating water to keep the plant cool and allowing for transpiration.
These temperature ranges will vary depending on variety and species of plant. For instance, some orchids require more than a 10F-15F difference between daytime and nighttime temperatures in order to flower.
Ideal temperature also varies depending on whether or not CO2 is being introduced to the environment. A more suitable daytime temperature when the air is being enriched with CO2 is 80F-85F. This temperature range promotes the exchange of gases between the plants and the environment. Also, it can speed up the process of photosynthesis. A plant in an environment at 86F can perform carbon extraction from CO2 twice as fast as at 68F. It is still recommended that the night time temperature drop no more than 15F from that of the daytime temperature. There is another relationship between temperature and the absorpsion of gases by plants that many hobbyist growers are aware of. That is the relationship between the temperature of the water in your reservoir and the amount of oxygen the water can hold. The best range that your reservoir can be between is 60F-75F. Ideally the reservoir temperature should be at 65F because this level contains the most oxygen. Also this temperature will help control transpiration (the act of drawing up nutrients by evaporating water through out the leaves), and humidity levels. Buying a simple floating thermometer will allow you to know where you fit in this range.
Another great reason for regulating the temperature in your grow room is that biological processes can be sped up exponentially by every degree. This is true for your plants as well as the potential pests that may invade your grow room. Pests such as spider mites can reproduce up to 10 times faster with every degree the temperature rises. These pests can destroy a garden in no time flat, you really do not want to make it any easier for them. With a daytime temperature at a steady 72F and nighttime temperature of 65F it is much easier to control and destroy spider mite, thrip, and many other pest populations.
The same principal can be applied to the prevention and control of fungi, molds, mildews, and bacteria, which can spread more rapidly when temperatures in the grow room or reservoir exceed 90F. Also, the warmer the air, the more water it can retain which means humidity levels can easily go beyond the recommended 40-50%. This high humidity coupled with lower nighttime temperatures can cause condensation to form on leaves. This will invite molds, mildews, fungi, and bacteria to take over you grow space. With high temperatures the likely-hood of losing control of the problem, such as powdery mildew, is very high. Once control is lost your plants may be the next to go.
Temperature is also very important when it comes to starting seeds and getting cuttings to root. Placing seedling trays on a heating mat will reduce germination time dramatically. Speeding up germination time usually leads to stronger and healthier plants. Also, less time spent between crop cycles makes a garden efficient. More harvests provided in less time can equal big bucks in the pockets of professional growers. The ideal temperature to achieve these results is 80F. Any higher and you risk burning the roots. Also, many seeds simply will not germinate at temperatures over 90F. The seeds will become dormant and never sprout.
The same principal used for seeds is used on cuttings to coax roots out quicker. The sooner cuttings can establish roots the better. If roots can be forced quickly they will grow strong and stay strong. A bottom temperature of 80F-85F, roughly 10F warmer than the air, will speed up rooting time and help to jump start those roots once they do begin. Let the temperature get too high or too low and roots growth will be hindered or they will never grow at all. Using the proper technique and the proper temperature for bottom heat not only can rooting time be sped up from 2 weeks to as little as 3 days, but the survival rate of your cuttings will drastically improve.
Products such as digital ballasts, exhaust fans and cutting heating mats all will help the a gardener save precious time and money. Ventilation of any garden is very important. This is especially true when the garden is indoors. Good ventilation will provide fresh air and help maintain proper temperatures. The best way to keep the air in your garden with an ideal temperature of 70F -75F is with an exhaust fan. Exhaust fans are used to remove hot, stale air from your grow space and bring in cooler air from either an adjacent room or outdoors. The proper fan for your room can exhaust your room in less than five minutes. This is essential during hot summer months when the outside temperature can cause the temperature in the grow room to rise past 90F. Your exhaust fan should be timed to turn on at least once an hour for five minutes.
An easier way to have the temperature of your room stay in the range that you want is to have your fan hooked up to a thermostat. Simple thermostats will plug right into the wall and the fan will plug into it. The thermostat will have a coil on it that will tell temperature. Place the thermostat in the room and set it to the temperature that you wish the air not to exceed. When the room reaches that temperature the thermostat will trigger the fan to come on. The fan will then exhaust the room until the thermostat reads that the grow room is no longer at that temperature.
An oscillating fan aimed at the space between your bulbs and the canopy can be quite beneficial. Oscillating fans won’t lower the overall temperature of the garden but it will help to keep heat from building up directly around the plants. Using exhaust and oscillating fans are simple, almost foolproof ways of making sure that your indoor garden never exceeds certain temperatures. The same thing can be done for rooms that temperatures drift too low (below 62F). A space heater can be plugged into a thermostat and set to come on when your growing environment gets too cold.
High reservoir temperatures can cause the gardener many problems. This can cause water to evaporate, which concentrates the nutrient solution. High temperature also increases the possibility of water-born disease. If this is the case it may be time to invest in a reservoir chiller. Reservoir chillers cool the nutrient solution by circulating it through refrigerated coils set by a thermostat. When the temperature gets high, reservoir chillers are worth every penny.
Light movers are an excellent option for indoor growers who need to distribute the heat underneath the bulb. Light movers are also a great alternative from growers who need more evenly distributed lighting but do not want to add another lamp. By moving the lamp around the grow space, light movers help keep heat from accumulating directly under the lamp. Instead heat is spread out more evenly. This also means that lamps can be moved much closer to the tops of the plants without burning the tender leaves or delicate flowers. I have used rail light movers in the past.They are interesting to say the least and do work to ensure heat distribution. Maintenance on them is a little different and they tend to be noisy. Another time I will go into what I have tried and used over the years and what I prefer to use. Remember that light strengths (lumens) increase exponentially as it moves towards the source. A plant two feet away from its light source will only receive a quarter of the lumens that a plant one foot away will.
There are two common kinds of light movers. The first systems will consist of two or more lamps in small reflectors attached to arms that turn constantly in a circle. The other is the lights rail system, which consists of one or more lamps in reflectors constantly moving back and forth down a rail. Light movers not only provide more intense light with the lamp closer to the plants but they can provide far more even lighting. This allows three lights with a light mover to do the work of four. Another overlooked benefit of light movers is what the motor for the mover will be using around 1 amp, which is around 75watts-100watts. With 1000watts HID at 120 volts just of 9 amps, with house circuuits generally designed for 15 amps -20 amps, any way to save electricity is essential.
The sooner cuttings are established the better and this means growing roots fast. The best way to have almost any cutting root quickly is to have and maintain a bottom temperature of 80-85F. Keeping the roots 10F warmer than the air will speed up rooting on cuttings and drastically improve their survival rate. The best way to achieve this is by having a heating mat under the tray of cuttings. This can speed up rooting clones from two weeks to three days. Personally I have never used a heating mat in my own garden. I have not needed to as I am not located in an area of the country that weathers go through too many extremes, lucky me!
Friday, May 10, 2013
Wednesday, May 8, 2013
city council
Sunday, May 5, 2013
Friday, May 3, 2013
find a system
What are the different types of hydroponic systems available?
Nutrient Film Technique (NFT)
The nutrient film technique was developed in the mid 1960s in England by Dr. Allen Cooper. He was interested in building a low cost, large scale system to be used in parts of the world where soil quality is poor. NFT ensures a continuous flow of nutrient laden solution over the root system, allowing the plants to feed constantly, resulting in increased productivity and yield. NFT systems use little or no growing medium, thereby keeping operating costs down, but because of the lack of medium to act as a buffer, plants may suffer if a long-term power failure occurs. Trellising may be required when growing larger plants in NFT systems because of the lack of medium to hold the plants in place.
Ebb & Flow
An Ebb and Flow system consists of a growing bed in which individual containers filled with medium hold your plant's root systems. The growing medium also acts as a buffer, holding water and nutrients around the root system, and reducing the risk of crop loss due to power or equipment failure. The growing bed is flooded periodically to feed and water the plants and allowed to drain freely to pull oxygen into the root zone. Ebb and Flow systems' low maintenance, high productivity, and ease of use make them among the most popular hydroponic systems for not only the beginner, but for the advanced gardener as well.
Top Feed Systems (drip systems)
A top feed or drip system operates by using a pump and tubing to deliver nutrient solution to the top of the growing medium, where the solution trickles through the medium and then returns to the reservoir. Top Feed systems can use a variety of growing media and are available in a wide range of configurations. Top Feed systems are reliable, require little maintenance, and are suited for all types of plant growth.
Aeroponic Systems
Aeroponics systems use pumps and sprayers to continually spray oxygen rich nutrient solution directly onto the root systems of your plants. Aeroponic systems have shown extremely fast growth rates and clone- rooting success rates due to the large amount of diffused oxygen available in the nutrient solution. These systems successfully propagate very hard to root plants. Very little growing medium in these systems reduces operating costs.
Air Pump Systems
An Air Pump system utilizes a small air pump of the type used in an aquarium to constantly circulate oxygen-rich nutrient solution through the growing medium. This method of hydroponics does supply more dissolved oxygen to the root system of the plant than other methods can, although not as much as the aeroponic method does. Air Pump systems are available in a variety of configurations and sizes.
What are the different types of hydroponic media?
Rockwool
Rockwool is a fairly recent addition to the types of growing mediums available on the market. This sterile, porous, nondegradable medium is composed primarily of granite or limestone which is melted and spun like cotton candy. Rockwool is then formed into blocks, sheets, cubes, slabs, or flocking. Rockwool absorbs moisture without holding nutrients, and even when it is completely saturated still retains 20% air for your root system.
L.E.C.A. (Lightweight Expanded Clay Aggregate)
L.E.C.A. stone is a type of clay which is super-fired to create a porous medium. It is also heavy enough to provide secure support for your plants' root systems. This non-degradable, sterile growing medium holds moisture, has a neutral pH, and also will wick nutrient solution to the root systems of your plants. L.E.C.A. is often the growing medium of choice of novices and professionals alike because it is easy to use.
Perlite
Perlite is primarily composed of minerals subjected to intense heat which expand and become very absorbent. This material is light, has a neutral pH, excellent wicking action, and is very porous. Perlite is used in a wide variety of hydroponic systems because of its ability to hold moisture and nutrients as well as air, and also because it is very easy to use.
Coconut Fiber
An alternative to using rockwool, Coconut fiber is the first "organic" medium to offer high performance in modern hydroponic applications. Coconut fiber can also be added into soil mixtures to increase water holding capacity. Coconut fiber holds more oxygen than rockwool and is pH neutral. Available as compressed bricks, when Coconut fiber is soaked in water it expands to 6 times its compressed size. Many growers have found that a 50/50 mix of coconut fiber and L.E.C.A is the perfect organic medium.
the below photo is my 48 bucket ebb and flow system
tips for max yield
1. Electro-Conductivity (EC) or Conductivity Factor (cF) can be expressed as either milliSiemens (mS), cF, or parts per million (PPM) 1 mS = 10cF = 700ppm.
2. The pH and electro-conductivity values specified here are given as a broad range. It should be noted that specific plant requirements will vary according to regional climatic conditions, and from season to season within that region.
3. As a general rule, plants will have a higher nutrient requirement during cooler months, and a lower requirement In the hottest months. Therefore, a stronger nutrient solution should be maintained during winter, With a weaker solution during summer when plants take up and transpire more water than nutrients.
4. KNOW YOUR CROP. Plant EC or cF may vary according to the stage of growth. For example, cucumber prefer 20cF when establishing, and 25cF after the first harvest. Between 5 and 7 weeks after first harvest, the optimum cF is 17.
5. The nutrient solution should be discarded at regular intervals. Should there be a requirement to flush the growing bed, the system should be flushed with fresh nutrients (run-to-waste) rather than water to avoid starving or stressing plant.
What is Salinity?
Salinity is a measure of how much salt is in the water.
Salinity is usually measured in parts per thousand (ppt) units. Parts per thousand is how many grams of salt are dissolved per liter of water.
Why is Salinity Important?
All plants, animals, bacteria, and algae need a certain salinity range in order to survive. Changes in salinity can kill an organism.
The salinity in the Neuse River in North Carolina, for example, can range from 0ppt to 35ppt.
on the subject of deficiencies
(N) is primary to plant growth. Plants convert nitrogen to make proteins essential to new cell growth. Nitrogen is mainly responsible for leaf and stem growth as well as overall size and vigor. Nitrogen moves easily to active young buds, shoots and leaves and slower to older leaves. Deficiency signs show first in older leaves. They turn a pale yellow and may die. New growth becomes weak and spindly. An abundance of nitrogen will cause soft, weak growth and even delay flower and fruit production if it is allowed to accumulate.
Phosphorus
(P) is necessary for photosynthesis and works as a catalyst for energy transfer within the plant. Phosphorus helps build strong roots and is vital for flower and seed production. Highest levels of phosphorus are used during germination, seedling growth and flowering. Deficiencies will show in older leaves first. Leaves turn deep green on a uniformly smaller, stunted plant. Leaves show brown or purple spots. NOTE: Phosphorus flocculates when concentrated and combined with calcium.
Potassium
(K) activates the manufacture and movement of sugars and starches, as well as growth by cell division. Potassium increases chlorophyll in foliage and helps regulate stomata openings so plants make better use of light and air. Potassium encourages strong root growth, water uptake and triggers enzymes that fight disease. Potassium is necessary during all stages of growth. It is especially important in the development of fruit. Deficiency signs of potassium are: plants are the tallest and appear healthy. Older leaves mottle and yellow between veins, followed by whole leaves that turn dark yellow and die. Flower and fruit drop are common problems associated with potassium deficiency. Potassium is usually locked out by high salinity.
Magnesium
(Mg) is found as a central atom in the chlorophyll molecule and is essential to the absorption of light energy. Magnesium aids in the utilization of nutrients, neutralizes acids and toxic compounds produced by the plant. Deficiency signs of magnesium are: Older leaves yellow from the center outward, while veins remain green on deficient plants. Leaf tips and edges may discolor and curl upward. Growing tips turn lime green if the deficiency progresses to the top of the plant.
Calcium
(Ca) is fundamental to cell manufacture and growth. Soil gardeners use dolomite lime, which contains calcium and magnesium, to keep the soil sweet or buffered. Rockwool gardeners use calcium to buffer excess nutrients. Calcium moves slowly within the plant and tends to concentrate in roots and older growth. Consequently young growth shows deficiency signs first. Deficient leaf tips, edges and new growth will turn brown and die back. If too much calcium is applied early in life, it will stunt growth as well. It will also flocculate when a concentrated form is combined with potassium.
Sulphur
(S) is a component of plant proteins and plays a role in root growth and chlorophyll supply. Distributed relatively evenly with largest amounts in leaves which affects the flavor and odor in many plants. Sulphur, like calcium, moves little within plant tissue and the first signs of a deficiency are pale young leaves. Growth is slow but leaves tend to get brittle and stay narrower than normal.
Iron
(Fe) is a key catalyst in chlorophyll production and is used in photosynthesis. A lack of iron turns leaves pale yellow or white while the veins remain green. Iron is difficult for plants to absorb and moves slowly within the plant. Always use chelated (immediately available to the plant) iron in nutrient mixes.
Manganese
(Mg) works with plant enzymes to reduce nitrates before producing proteins. A lack of manganese turns young leaves a mottled yellow or brown.
Zinc
(Z) is a catalyst and must be present in minute amounts for plant growth. A lack of zinc results in stunting, yellowing and curling of small leaves. An excess of zinc is uncommon but very toxic and causes wilting or death.
Copper
(C) is a catalyst for several enzymes. A shortage of copper makes new growth wilt and causes irregular growth. Excesses of copper causes sudden death. Copper is also used as a fungicide and wards off insects and diseases because of this property.
Boron
(B) is necessary for cells to divide and protein formation. It also plays an active role in pollination and seed production.
Molybdenum
(Mo) helps form proteins and aids the plant's ability to fix nitrogen from the air. A deficiency causes leaves to turn pale and fringes to appear scorched. Irregular leaf growth may also result.