Monthly Archives: June 2018

• Hydroponic is the act of raising plants without using soil, but rather in a water medium with nutrients.
• The plants are placed in a hydroponic system that supplies the required nutrients to the roots with the help of the water medium.
• The use of hydroponic has helped farmers to evade serious seedling diseases and pests like fungus and gnats, which mostly attack in moist soils.
• Media like coconut fibre, plugs, and peat pots have necessary nutrients and ensure that the seeds have a healthy growth.
• Rockwool or oasis can serve as a medium, the seedlings can be transplanted along with the cube into a complete hydroponic system later.
• Rapid rooters are mostly used as a medium as they have large numbers of important microbes and Mycorrhizal fungi that help in colonizing the root thus maximizing uptake of nutrients by the plant and evade serious diseases.

Other options:-

• Other than rapid rooters, there are other hydroponic options you can go for like, rock wool, coconut fibre, peat and oasis cube.
• While the rapid rooters retain a lot of water, oasis and coir retain very little water.
• The rock wool has a high PH concentration; therefore, the cubes should be rinsed in the solution of both water and vinegar to neutralize the PH before putting the seeds in the cubes to grow.
• Mix a teaspoon of vinegar in a cup half-filled with water and dip the cubes into the resulting solution shaking off the excess.
• Rock wool needs more attention because it is alkaline in nature.

Location: -

• The container should be placed where it can receive maximum light.
• If you choose to grow your seeds in the house, the convenient places are like on a table or near a window where there is partial light either in the morning or in the afternoon.
• In case you want to grow outside, then you should select a partially sunny location like a porch.
• The container should be away from heavy rainfall and winds.
• Since the container is small and portable, it should be moved from one place to another to protect it from bad weather.

Maintenance: -

• Water should be added only when the cubes start to get dry. Because much water favours the development of molds on the rock wool.
• On the other hand, if there is no water for a long time the seeds will not germinate. Thus, the cubes should be moist but not wet or dry.
• When the seedlings reach 2 inches in height, add diluted nutrient solution or fish water to the water in the container. This will greatly boost the root growth.

Transplanting: -

• The seedlings are ready for transplanting to a hydroponics grow system when they reach 3-4 inches in height. Look for 3 to 4 true leaves.
• Fill the net pot with clay pellets until it is half full. Which supports the plants.
• The best time of day to plant is in the late afternoon when the sun is not hot, and the wind has calmed down. By taking advantage of this time of day, the new plants have overnight to acclimate.
• Strong sun and wind are very hard on new transplants. Unless watered carefully, and in some cases provided with some shelter from the wind and sun, they can severely wilt.
• This places the plants under stress at the very beginning of their growing cycle and is not a good idea because sometimes they never bounce back and don't thrive as well as they could have.

Growing peppers in aquaponic units: There are many varieties of peppers, all varying in colour and degree of spice, yet from the sweet bell pepper to the hot chili peppers (jalapeno or cayenne peppers) they can all be grown with aquaponics. Peppers are more suited to the media bed method but they might also grow in 11 cm diameter NFT pipes if given extra physical support.

Growing conditions: Peppers are a summer fruiting vegetable that prefers warm conditions and full sun exposure. Seed germination temperatures are high: 22 - 34 °C. Seeds will not germinate well in temperatures 30 - 35 °C lead to floral abortion or fallout. In general, spicier peppers can be obtained at higher temperatures. The top leaves of the plant protect the fruit hanging below from sun exposure. As with other fruiting plants, nitrate supports the initial vegetative growth (optimum range: 20 - 120 mg/litre) but higher concentrations of potassium and phosphorus are needed for flowering and fruiting.

Growing instructions: Transplant seedlings with 6 - 8 true leaves to the unit as soon as night temperatures settle above 10 °C. Support bushy, heavy-yielding plants with stakes or vertical strings hanging from iron wires pulled horizontally above the units. For red sweet peppers, leave the green fruits on the plants until they ripen and turn red. Pick the first few flowers that appear on the plant in order to encourage further plant growth. Reduce the number of flowers in the event of excessive fruit setting to favour the growing fruits to reach an adequate size.

Harvesting: Begin harvesting when peppers reach a marketable size. Leave peppers on the plants until they ripen fully by changing colour and improve their levels of vitamin C. Harvest continually through the season to favour blossoming, fruit setting and growth. Peppers can be easily stored fresh for 10 days at 10 °C with 90 - 95 per cent humidity or they can be dehydrated for long-term storage.

pH: 5.5 - 6.5

Plant spacing: 30 - 60 cm (3 - 4 plants/m2, or more for small-sized plant varieties)

Germination time and temperature: 8 - 12 days; 22 - 30 °C (seeds will not germinate below 13 °C)

Growth time: 60 - 95 days

Temperature: 14 - 16 °C night time, 22 - 30 °C daytime

Light exposure: full sun

Plant height and width: 30 - 90 cm; 30 - 80 cm

Recommended aquaponics method: media beds

Reference: http://www.fao.org/3/a-i4021e.pdf

Potassium is a paramount macro-element for overall survival of living things. It is an abundant mineral macronutrient present in both plant and animals tissues. It is necessary for the proper functioning of all living cells. Potassium is relatively abundant in the earth's crust making up to 2.1% by weight. Potassium is mined in the form of potash (KOH), sylvite (KCl), Carnallite and Langbeinite. It is not found in free nature.

Importance of potassium to plants

Potassium is an indispensable constituent for the correct development of plants. It is important in photosynthesis, in the regulation of plants responses to light through opening and closing of stomata. Potassium is also important in the biochemical reactions in plants. Basically, potassium (K) is responsible for many other vital processes such as water and nutrient transportation, protein, and starch synthesis.

Potassium Uptake

Bio-availability and uptake of K by plants from the soil vary with a number of different factors. The rate of respiration by plants is largely the determining factor for proper uptake and transport of potassium by plants. Its uptake is dependent on sufficient energy (ATP). Potassium plays a vital role in the translocation of essential nutrients, water, and other substances from the roots through the stem to the leaves. It is also made available through fertilizers in the form of K2O. Plant tissues analyze the form of these fertilizers and convert it into a more bio-available form. It is absorbed in the form of ions- K+.

Functions of Potassium in plants

Potassium (K) essentially plays a major role in plant physiological processes. Therefore, it is required in large amounts for proper growth and reproduction in plants. It is considered vital after nitrogen as far as nutrients needed by plants are concerned. It is also termed "the quality nutrient" for its contributing factor in a number of biological and chemical processes in plants. Here is why Potassium is important in plants:

• Potassium regulates the opening and closing of stomata thus regulating the uptake of CO2 thus enhancing photosynthesis.
• It triggers activation of important biochemical enzymes for the generation of Adenosine Triphosphate (ATP). ATP provides energy for other chemical and physiological processes such as excretion of waste materials in plants.
• It plays a role in osmoregulation of water and other salts in plant tissues and cells.
• Potassium also facilitates protein and starch synthesis in plants.
• It activates enzymes responsible for specific functions.

Potassium deficiency in plants

Regardless of its availability from soils, potassium deficiency may occur and might start from the lower leaves and progress towards other vital parts of the plants. Deficiency might cause abnormalities in plants affecting reproduction and growth. Severity depends on with the type of plant and soil. Some of the potassium deficiency symptoms may include:

• Chlorosis: May cause yellowing of leaves, the margin of the leaves may fall off, and also lead to shedding and defoliation of the leaves.
• Stunted growth: Potassium being an important growth catalyst, its deficiency or insufficient might lead to slow growth or poor developed roots and stems.
• Poor resistance to ecological changes: Reduced availability of potassium will directly result in less fluid circulation and translocation of nutrients in plants. This will directly make plants susceptible to temperature changes.

Importance of potassium in agriculture

Potassium is important in agriculture and soil gardening. It is used as a constituent in artificial fertilizers. Potassium fertilizers have been seen to increase crop yields, enhance production of grains rich in starch and protein content of plants. Additionally, potassium fertilizers may help improve plants immunity to weather changes, diseases, and nematodes.

Potassium is majorly used in hydroponics to improve root growth and enhance drought tolerance. It also enhances the building of cellulose and thus reduces lodging.

Cherry Tomato: -Â

Tomatoes are an excellent summer fruiting vegetable to grow using all available methods although physical support is necessary.

A higher nitrogen concentration is preferable during the early stage to flower stage. However, potassium should be present from the flowering stage to fruit setting to growth.

Tomatoes are rich in vitamins A and C, low in calories and a source of lycopene (the "Red" in tomatoes), which has been tapped as a cancer-fighting agent.

If you have experience in growing tomato you know that to get the high-quality products and good yields with a limited space can be quite a challenge.

We'll try to consolidate all important things that you need to know if you want to grow tomatoes, have high-quality products and great yields in your greenhouse. We'll also share our experience and you'll see great benefits of aquaponic systems for profitable commercial tomato production.

Tomato is one of the most demanded vegetables. In the season but also out of the season. It is used as a fresh produce but also an input for the production of many different products like sauces. One of the greatest advantages is that it grows in the air and we can use a lot of greenhouse height for our production.

The main advantages of growing tomatoes in protected spaces (greenhouses) compared to other crops are:

• It is highly attractive and demanded product
• We can have very high yields per sqm
• There are many hybrids that are resistant to diseases.

Growing Conditions: -

• When you have set up your aquaponic system and decided to grow tomato you need to pay attention to some details. If you make mistakes, in the beginning, you will not see problems usually until it's too late to fix them.

1. Type of aquaponic system?
2. How to band tomatoes for the best vertical growth?
3. How to make tomato grow faster?

• Each and every part of the aquaponic system that is not synched to specific natural laws can create problems in the future. These problems can be insignificant but sometimes these problems can lead to total disaster. For that reason, it is important to have all the information and to understand each part of the system.
• The first and most important factor is to choose the right aquaponic system for tomato production.
• Out of all aquaponic systems, BED system is probably the most convenient for many types of crops. But it is not a profitable system. Because it is quite robust, it takes a lot of space and is quite expensive to construct.
• For profitable tomato cultivation, one of the best aquaponic systems is DUTCH BUCKET

• In Dutch bucket aquaponic system we are using a number of buckets for growing our crops in them. In buckets, we put any growing media that is suitable for aquaponics. When we are irrigating crops the water is moving through growing medium and feeding the root of our plants.
• We need to make sure that there is always some water in the bottom of the bucket.
• We can achieve this by drilling drainage holes on a certain height of the bucket. For this system to work we do not need any additional siphons.
• When constructing Dutch bucket aquaponic system pay special attention to the following

1. Greenhouse space usage
2. Pipes and nozzle clogging
3. Space for roots development
4. Bucket drainage

• Tomatoes prefer warm temperatures with full sun exposure. Below 8-10°C, the plants stop growing, and night temperature 13-14 encourage fruit set. Temperature above 40°C cause floral abortion and poor fruit setting.
• Tomatoes have a moderate tolerance to salinity, which makes them suitable for areas where pure freshwater is available. However, higher salinity at fruiting stage improves quality of the products.

Planting Instructions: -

• Set stakes or plant support structures before transplanting to prevent root damage.
• Transplant the seedlings into units 3-6 weeks after germination when the seedling is 10-15 cm and when the night time temperatures are constantly above 10°C.
• In transplanting the seedlings, avoid waterlogged conditions around the plant collar to reduce any risk of diseases.
• Once the tomato plants are about 60 cm tall, start pruning the unnecessary upper branches. Remove the leaves from the bottom to 30cm of the main stem for better air circulation and reduce fungal incidence.
• Remove the leaves covering each of the fruiting branches soon before ripening to favour nutrition flow to the fruits and to accelerate maturation.

Harvesting: -

• Most cherry tomato plants will start flowering in about a month. Flowers will be followed by tiny green fruits. After a few weeks, those turn into full-blown cherry tomatoes you can harvest.
• A truly ripe cherry tomato will come off its stem very easily and is well worth waiting an extra day for, so hold off on picking them until they're ripe. Then, pluck individual fruits every day for best results. With luck, your plant will continue to produce right up until winter. If the weather turns unseasonably cool or an early frost threatens, you can tuck an old sheet over and around the plant to extend your harvest season.
• Fruits can be easily maintained for 2-4 weeks at 5-7°C under 85-90 percentage relative humidity.

Tips: -

• PH: 5.5-6.5
• Plant spacing: 40-60cm (3-5 plants/sqm)
• Germination time and temperature: 4-6 days and 20-30 °C
• Growth time: 50-70 days till the first harvest; fruiting 90-129 days up to 8-10 months.
• Optimal temperature: 13-16°C night, 22-26 °C day
• Light exposure: full sun
• Recommended methods: Media Beds and DWC

• Growing hydroponics lettuce is one of the easiest and the best ways to start hydroponic gardening.
• Lettuce is a simple to grow all round plant that can ensure you get great results when grown in soil, as long as you keep pests off it.
• This is where growing lettuce hydroponically will make perfect sense and will be a terrific first task for any hydroponic setup.
• Lettuce hydroponics will typically look after themselves and do not need a lot of nutrients as other heavy feeding plants like tomatoes.
• It's obviously still a great practice to check out your growing hydroponic lettuce plants every day for pests or other problems, though these problems are considerably decreased with hydroponics, particularly indoor hydroponics.
• Actually, the only issue you could come across when growing hydroponic lettuce at home is size.
• Lettuce is in high demand and has a high value in urban and peri-urban zones, which makes it a very suitable crop for large-scale commercial production.

Note: -

• Check lettuce for signs of downy mildew, powdery mildew or gray mold and get rid of any infected plants.
• Water that's heavily chlorinated can lead to issues with lettuce. You should use lightly chlorinated city water or well water.

Lettuce varieties: -

Lettuce can be characterized based on their leaf and head formation.

Crisp head or iceberg: -

• Crisp head lettuce, more commonly known as iceberg, has a tight head of crisp leaves. Often found in the local salad bar, it is actually one of the most difficult lettuce varieties to grow. This lettuce variety is not fond of hot summer temperature or water stress and may rot from the inside.
• Start iceberg lettuce via seed directly sown 18-24 inches apart or started indoors and then thinned 12-14 inches between heads. Some iceberg lettuce varieties include Ballade, Crispino, Ithaca, Legacy, Mission, Salinas, Summertime and Sun Devil, all of which mature in 70-80 days.

Romaine or Cos: -

• Romaine varieties are typically 8-10 inches tall and upright growing with spoon-shaped, tightly folded leaves and thick ribs. Colouration is medium green on the exterior to a greenish white inside with the outer leaves.
• Sometimes being tough whilst the interior foliage is tender with wonderful crunch and sweetness. Different types of this lettuce are Brown Golding, Chaos Mix black, chaos Mix white, Dark green Romaine, De Morges Braun, Hyper Red Rumple, Little Leprechaun. All of which mature within around 70 days.

Butterhead, Boston or Bibb: -

• One of the more delicate varieties of lettuce, Butterhead is creamy to light green on the inside and loose, soft and ruffled green on the exterior. These different types of lettuce may be harvested by removing the entire head or just the outside leaves and easier to grow than crispheads, being more tolerant of conditions.
• Less likely to bolt and rarely bitter, the butterhead lettuce varieties mature in about 55-75 days and spaced similarly to the crispheads. These varieties of lettuce include Blushed Butter Oak, Buttercrunch, Carmona, Divina, and Yugoslavian red.

Growing Conditions: -

• Lettuce is a winter crop. For head growth, the night air temperature should be 3-12°C, with a day temperature of 17-28°C.
• The generative growth is affected by photoperiod and temperature extended daylight warm conditions(>18°C) at night cause bolting. Water temperature >26°C may also result in bolting and leaf bitterness.
• The plant has low nutrient demand; however higher calcium concentrations in water help to prevent tip burn in leaf in summer crops.
• The ideal PH is 5.8-6.2. but lettuce still grows well with a PH as high as 7, although some iron deficiencies might appear owing to reduced bio-availability of this nutrient above neutrality.

Growing instructions:

• Seedlings can be transplanted in units at three weeks when plants have at least 2-3 true leaves. Supplemental fertilization with phosphorous to the seedlings in the second and third weeks favours root growth and avoids plant stress at transplant.
• Take care not to damage the roots of plants during transplanting because such damage will make the plant susceptible to disease infection.
• It is advisable to transplant the plant in the late afternoon to prevent them becoming stressed in the heat of the day under high UV conditions.
• The transplant will begin to adapt to the new location at night and roots will start to grow into the solution below.
• Make sure the plants base is touching the flow of nutrient solution below when transplanting.
• To achieve crisp sweet lettuce, grow plants at a fast pace by maintaining high nitrate levels in the unit. When air and water temperatures increase during the season, use bolt -resistant(summer) varieties. If growing in media beds, plant new lettuces where they will be partially shaded by taller nearby plants.

Lighting: -    

• Lettuce grows up vigorously with fluorescent lighting. It would obviously grow far better with the more expensive lighting specially created for hydroponics, like HID and some of the latest LED grow lights for indoor plants.
• However, regarding cost-effectiveness, from the viewpoint of the small-scale grower, fluorescent lighting is the best.
• These are cool weather crops, so too much heat can, in fact, delay germination.

Harvesting Hydroponics lettuce: -

Hydroponics harvesting depends on the following factors

• First, this will depend on what type you are growing. Romaine takes up to 85 days. Bibb and Loose-leaf lettuce can take 45 to 55 days.
• It has to do preference, growing lettuce indoors then you have to manage the environment and prolong your harvest.
• The majority of hydroponic lettuce production systems created around two ideas, either the floating raft system or the nutrient flow technique (NFT) system.
• The floating raft method is of particular interest since it is very affordable and can produce a lot of hydroponic lettuce.
• One of the major issues with raft systems is that the hydroponic lettuce nutrients solution is continually stagnant and will require that you use pumps to circulate water and produce important aeration.
• If the roots are not getting the precious oxygen, floating raft systems experience substantial loses of crops in the form of nutrients.

Below are some types that work well in hydroponics and with indoor artificial lighting:

• Royal Oakleaf is a darker green variety of lettuce that does extremely well in hydroponic growing systems and is also resistant to heat.
• Tango grows perfectly in cooler environmental only.
• Red Fire is a deep red, loose leaf variety that's ideal for both warm and cool climates.
• Green Ice is a variety of green loose that offers a long picking season.

Hydroponic romaine lettuce also does well though it usually takes a little bit longer to attain maturity.

Tips: -

• When you harvest lettuce with the roots attached, it will prolong storage life by two to four weeks.
• To prevent getting water mold such as Pythium or Phytophthora in your hydroponic lettuce system, use bleach to sanitize the tray between plants. If the lettuce gets infected, the plant is a loss.