Jun192018 by lmNo Comments

Hydroponic Systems Comparison Chart

Each type of hydroponic systems have their own unique characteristics and thus are optimal for different types of crops. Here is a table listing the pros and cons of each of the major types of hydroponic systems. There are also hybrid systems that attempt to take the positive characteristics of systems types while avoiding the downsides.

System Type	Distinguishing Characteristics	Pros	Cons	Tolerance to Pump Failure/Electricity Outage	Best for Growing	Not Ideal for Growing
Passive	No power is required to run the system. Most passive systems use a wick and capillary action to deliver the nutrient solution to the roots.	Does not require electricity Inexpensive to construct No moving parts	Does not scale well Requires grow medium Lower yields than other systems	Highest	Best used for educational growing projects, typically not used commercially or for production. Theoretically it can be used to grow any crop provided the system is scaled for size appropriateness.	Mass production crops, crops that need a lot of air in the root zone, crops with large root zones.
Flood and Drain (Ebb and Flow)	Nutrient solution delivered by pump into a tray then drained away in determined cycles	Energy efficient Scales well High rate of production, allows for many kinds of grow media High rate of germination	Reservoir capacities need to be higher Uses electricity	Medium	Seed starting. Crops that need well drained soil. Tomatoes, peppers.	Crops that need constant moisture. Salad greens, herbs, brassica family plants.
Drip	Nutrient solution delivered by pump to base of plant just above root zone Water pumps run continuously or on cycles depending on the water retention characteristics of the growing medium	High yields Low water usage Scales well Excellent for plants that like drainage	Requires electricity Drip lines are easily clogged	Low	Crops with large root zones, crops that require drainage, fruiting and flowering plants, crops that have a long growing cycle. Great for everything	Least practical for salad greens or crops harvested as a head.
Nutrient Film Technique (NFT)	Nutrient solution delivered to root zone via a thin film of liquid in a channel Water pumps run continuously	High yields Little to no medium required Easy to maintain Scales well	Not suitable for plants with large taproot systems	Lowest	Leafy greens, crops with shorter life cycles. Crops with smaller root zones. Lettuce, dandelion, chicory, herbs, basil, sage, brassica family plants used as salad greens.	Fruiting and flowering plants. Plants with larger root zones.
Deep Water	Roots are constantly submerged in a nutrient solution	Great for water loving crops Scales well	Reservoir capacities need to be higher Less useful for crops that need drainage	High	Water loving crops. Lettuce, chicory, dandelion, basil, cilantro, arugula, bok choy.	Crops that require heavy drainage. Large plants. Watercress (ironically).
Aeroponics	Nutrient solution delivered to root zone via a spray, mist or fog Water pumps run continuously Roots dangle in air	High yields Excellent for specialized tasks such as vegetative propagation or seed germination	Does not scale well Spray jets/misters/foggers clog easily	Lowest	Rooting cuttings, seed starting, seedlings, plants that like moderate drainage.	Large plants, plants with long life cycles.

Jun182018 by lmNo Comments

Introduction to hydroponic system types

Hydroponic System Types

The systems described below are the six most common methods (Wick System, Water Culture, Drip System, Flood and Drain, NFT and Aeroponics) for growing plants hydroponically, indoors and out.

Wick System

The wick system is a form of passive hydroponics (no moving parts), making it one of the most simple hydroponic growing methods. Plants are grown in an inert medium, such as perlite or coconut husk (coir) that absorbs or “wicks” nutrient solution from a reservoir, providing a constant supply of water and food to the plant’s roots. Because of their simplicity and lack of active parts, wick systems are protected against pump and power failure.

A Soda Bottle Planter is a simple example of a wick system.

Water Culture

Diagram of a Raft System with an Air Stone

Water culture systems are the simplest form of active hydroponics. They have a long history, dating back to hanging gardens of Babylon. Deep water systems were also used by the Aztecs, who grew crops on floating rafts on lakes.

Plant roots grow directly into the system’s reservoir. Roots are supplied oxygen by an air pump. Water culture systems can be built using repurposed glass mason jars, or plastic buckets/tubs as the reservoir. The plant is suspended from the lid in a net pot, allowing roots to grow through the holes into the water below.

In larger, commercial-scale systems, several plants are placed in a sheet of buoyant material that floats on nutrient solution like a raft. Water is generally held in a separate, larger reservoir and pumped up to the floating grow bed, then drained back down to the reservoir in a constant cycle. These systems is the least susceptible to pump and power failure.

Drip System

A drip system is another example of active hydroponics. Drip systems evolved from drip irrigation technology created for conventional soil agriculture. Plants are either grown in a substrate or suspended directly in water (like water culture systems). Nutrient solution is dripped onto the base of each plant stem, hydrating upper parts of the root system. The excess nutrient solution that isn’t used by the plant can be collected back into a reservoir for reuse: this is called a recirculating system.

Recycling excess nutrients is not always necessary. Drip systems can also be built so that excess nutrients drain out directly onto a soil garden underneath (drain-to-waste system). The downside to this, especially when using non-organic fertilizer, is that it is a form of agricultural runoff. Another drawback to drip systems is clogged nozzles and overheated drip lines. These issues can be abated by using different dripping techniques.

There are three major types of drip techniques: airlift, timber-controlled pump, and standard regulating dripper.

An airlift uses the rising action of air bubbles to carry water up a tube and out onto the top of a root system. It creates a drip-like effect that is very energy efficient.
Water pump cycling involves putting a water pump on a timer. When the pump is turned on, unobstructed water lines temporarily feed the plants with a continuous flow of nutrient solution until the pump turns off again.
A standard dripper regulates water flow to achieve a set amount of gallons per hour. Standard drippers are prone to clogging when used in hydroponic systems because mineral-based nutrients can leave salt residue that obstruct small spaces.

Many commercial tomato growers use a drip system in their greenhouses. Drip systems are also effective for almost any type of plant, as they allow for full-root nutrient coverage.

Flood and Drain (Ebb and Flow)

Flood and Drain is particularly effective for its low water usage and speedy plant development. This method was developed during World War II to grow tomatoes and lettuces for American troops in the Pacific, and was also one of the first documented uses of volcanic glass and rocks as a growing medium.

Plants are sown directly in a tray filled with growing medium. At intervals regulated by a timer, a water pump fills the tray with nutrient solution from a separate reservoir, saturating the growing medium and plant roots. The water begins to recirculate back into the reservoir through a one-way overflow valve. When the timer turns the pump off, the tray drains completely, providing the roots with oxygen.

This technique is used in our Germination System.

Nutrient Film Technique (NFT)

In NFT, or continuous-flow solution culture, plants are suspended and the roots grow down into a shallow, constant stream of nutrient solution, which is pumped into the channels from a separate reservoir. The parts of the roots that are not submerged in the water absorb oxygen for the plant. The channel containing the plants is built at an angle in order to use gravity to move the solution past the roots. Nutrient solution is then recycled back into the main reservoir. NFT systems scale well, as one central reservoir can hydrate several channels of plants. Unfortunately, this technique is very vulnerable in the event of pump and power failure.

NFT systems are most widely used for growing leafy greens and herbs such as lettuce and basil. The technology for NFT systems was developed primarily in the 1970s and 80s.

Nutrient Film Technique System on a Rooftop

Aeroponics

In an aeroponic system, plant roots are suspended in air and saturated with a constant mist of nutrient solution. An advantage to using aeroponics is that suspended plants receive 100% of the available oxygen at the root zone, as well as at the stems and leaves, which accelerates plant growth. NASA has been researching aeroponic techniques as a possible method for growing food in space, since a nutrient solution mist is more manageable than liquid in a zero-gravity environment.

Leaf Lift Systems has discovered that aeroponics speeds plant metabolism in young plants, resulting in a ~25% increased growth rate in experimentation settings when used in appropriate high-pressure aeroponic environments. This makes aeroponics particularly effective for germination and seedling development as well as cloning applications.

Jun92018 by lmNo Comments

Hydroponics Overview

HYDRO- + (GEO)PONICS] = [Water + The Science of Agriculture]

Literal Translation: Putting Water to Work.

While modern hydroponics has been used since the mid 1800’s it’s roots go back much further.

Chinampas, the Floating gardens of the Aztecs

To put it simply, hydroponics is the art of growing plants without soil. Our plants are grown in nutrient-infused water and kept in a precise, ideal growing environment that speeds plant growth, improves plant quality, prioritizes food safety, and heightens food flavor.

Hydroponics has been used in commercial agriculture for decades. More recently it has caught the attention of hobbyists, urban farmers, agriculturalists, and food science professionals as an excellent method of food production for many reasons:

No soil is required
Little to no agricultural runoff
Stable, high yields of produce, more productivity per square foot than traditional methods
Easy control of nutrition levels, pH, irrigation times, lighting, making production uniform, fast and consistent
Easy harvesting procedures
Year-round crop production with Controlled Environment Agriculture (CEA), the practice of growing food in a controlled environment (indoor/greenhouse)
No weather-related crop failures (indoor/greenhouse)
Substantially less water usage compared to open field farming
More control of food safety and security
Animal feed and compost can be created from post-harvest plant material
Allowance for ecosystem restoration—as farms move to urban centers they move out of the open field, allowing for that land to naturally restore itself over time
There are a few cons to hydroponic farming, many of which Boswyck Farms is working to address and/or minimize:

Negative consumer perception—many people do not understand hydroponics and therefore it is feared by some as being ‘franken-food’, unnatural, or less sustainable

It is extremely difficult to get organically certified and impossible to become naturally-grown certified
Disposal of rockwool and other grow medium can be a challenge
Zoning laws and policy for urban farming is unclear
Government incentives for urban farming are unclear, making usable rooftop space hard to access because building owners are not incentivized
Greater initial capital investment
Can require access to electricity
Currently does not meet requirements for organic certification in all states, countries, nations, etc.
Fewer educational resources available specific to hydroponics

Jun72018 by lmNo Comments

Optimal values for EC and pH

Optimal EC and pH values for hydroponically growing various crops

(This is a reprint from the web page https://hydroponic.co.za/hydroponics-quickstart/plant-phecppm/)

Plant PH/EC/PPM

EC – Electrical Conductivity

This is a measurement of the strength of a nutrient solution. It is also known as CF (Conductivity Factor), but since CF is only one decimal place away from EC, we will stick to EC. The measurement of EC is in milliSiemens per cm (mS/cm). It is a measurement of the strength of the nutrient solution as a whole and will not tell you if one or more of the nutrient salts is out of balance. Plants take up different nutrient salts at different stages of growth and in different climatic conditions, as well as different pH levels.. The speed that different nutrient salts are taken up also varies. For instance, nitrogen is taken up quite quickly, but calcium is a slow mover! For the home grower it is advisable to change the nutrient solutions at regular intervals, say every week in summer and every two weeks in winter.

If the EC rises, it means that the plants are taking up water faster than nutrients. This usually happens in hot weather, when the plant tries to keep cool. When this happens you add water until the required EC is reached. On the other hand, if the EC falls, the plant is taking up more nutrients than water, so you have to add more nutrients.

If you are a serious home grower you will obtain an EC meter and have the peace of mind that your plants are being fed optimally. The EC meter should be calibrated regularly, say once a month.

The practical use of EC readings becomes apparent when you realize that plants can be categorized into low, medium and heavy feeders. It follows from this that you should feed plants in the same category together from one reservoir if you are going to attain optimum results. If you feed lettuce with a high EC intended for tomatoes, the lettuce can become bitter. Likewise, if you feed tomatoes with a low EC, suitable for lettuce, the tomatoes will be tasteless!

This is the measure of acidity or alkalinity of a solution, on a scale of 1 to 14, where the neutral point is 7. Most plants in soil grow best in a pH6.5 – 7.0conditions, while hydroponically-grown plants prefer slightly more acid conditions. You should aim for a pH of between 5.5 and 6.5. This is the range within which nutrients are most available to plants.

A high pH can reduce the availability of iron, manganese, boron, copper, zinc and phosphorous to plants. A low pH can reduce the availability of potassium, sulphur, calcium, magnesium and phosphorus.

If the pH moves out of the desired range, it can be lowered by the addition of phosphoric or nitric acid to the solution, or raised by adding potassium hydroxide. There are pH adjusters better suited for vegetative growth, and others for fruiting phase.

The pH can be tested by using an indicator solution or a pH meter. This should be done daily. Calibration of the pH meter should be done weekly and the probe kept wet at all times.

Plant	pH	EC	PPM
African Violets	6.0-7.0	1.2-1.5	840-1050
Anthurium	5.0-6.0	1.6-2.0	1120-1400
Antirrhinim	6.5	1.6-2.0	1120-1400
Aphelandra	5.0-6.0	1.8-2.4	1260-1680
Artichoke	6.5-7.5	0.8-1.8	560-1260
Asparagus	6.0-6.8	1.4-1.8	980-1260
Aster	6.0-6.5	1.8-2.4	1260-1680
Banana	5.5-6.5	1.8-2.2	1260-1540
Basil	5.5-6.5	1.0-1.6	700-1120
Bean (Common)	6.0-6.5	1.8-2.4	1400-2800
Beans (Italian bush)	6.0-6.5	1.8-2.4	1400-2800
Beans (Lima)	6.0-6.5	1.8-2.4	1400-2800
Beans (Pole)	6.0-6.5	1.8-2.4	1400-2800
Beetroot	6.0-6.5	0.8-5.0	1260-3500
Begonia	6.5	1.4-2.4	980-1260
Bell peppers	6.0-6.5	1.8-2.8	1400-2000
Black Currant	6	1.4-1.8	980-1260
Blueberry	4.0 -5.0	1.8-2.0	1260-1400
Broad Bean	6.0-6.5	1.8-2.2	1260-1540
Broccoli	6.0-6.5	2.8-3.5	1960-2450
Bromeliads	5.0-7.5	0.8-1.2	560-840
Brussell Sprout	6.5-7.5	2.5-3.0	1750-2100
Cabbage	6.5-7.0	2.5-3.0	1750-2100
Caladium	6.0-7.5	1.6-2.0	1120-1400
Canna	6	1.8-2.4	1260-1680
Capsicum	6.0-6.5	1.8-2.2	1260-1540
Carnation	6	2.0-3.5	1260-2450
Carrots	6.3	1.6-2.0	1120-1400
Cauliflower	6.0-7.0	0.5-2.0	1050-1400
Celery	6.5	1.8- 2.4	1260-1680
Chicory	5.5-60	2.0-2.4	1400-1600
Chives	6.0-6.5	1.8-2.4	1260-1540
Chrysanthemum	6.0-6.2	1.8-2.5	1400-1750
Cucumber	5.8-6.0	1.7-2.5	1190-1750
Cymbidiums	5.5	0.6-1.0	420-560
Dahlia	6.0-7.0	1.5-2.0	1050-1400
Dieffenbachia	5	1.8-2.0	1400-1680
Dracaena	5.0-6.0	1.8-2.4	1400-1680
Eggplant	5.5-6.5	2.5-3.5	1750-2450
Endive	5.5	2.0-2.4	1400-1680
Fennel	6.4-6.8	1.0-1.4	700-980
Ferns	6	1.6-2.0	1120-1400
Ficus	5.5-6.0	1.6-2.4	1120-1680
Fodder	6	1.8-2.0	1260-1400
Freesia	6.5	1.0-2.0	700-1400
Garlic	6	1.4-1.8	980-1260
Gerbera	5.0-6.5	2.0-2.5	1400-1750
Gladiolus	5.5-6.5	2.0-2.4	1400-1680
Hot Peppers	6.0-6.5	1.8-2.8	1400-2000
Impatiens	5.5-6.5	1.8-2.0	1260-1400
Lavender	6.4-6.8	1.0-1.4	700-980
Leek	6.5-7.0	1.4-1.8	980-1260
Lemon Balm	5.5-6.5	1.0-1.6	700-1120
Lettuce	5.5-6.5	0.8-1.2	560-840
Marjoram	6	1.6-2.0	1120-1400
Marrow	6	1.8-2.4	1260-1680
Melon	5.5-6.0	2.0-2.5	1400-1750
Mint	5.5-6.0	2.0-2.4	1400-1680
Monstera	5.0-6.0	1.8-2.4	1400-1680
Mustard Cress	6.0-6.5	1.2-2.4	840-1680
Okra	6.5	2.0-2.4	1400-1680
Onions	6.0-6.7	1.4-1.8	980-1260
Pak-choi	7	1.5-2.0	1050-1400
Palms	6.0-7.5	1.6-2.0	1120-1400
Parsley	5.5-6.0	0.8-1.8	560-1260
Parsnip	6	1.4-1.8	980-1260
Granadilla	6.5	1.6-2.4	840-1680
Paw-Paw	6.5	2.0-2.4	1400-1680
Pea	6.0-7.0	0.8-1.8	980-1260
Peas (Sugar)	6.0-6.8	0.8-1.8	980-1260
Pepino	6.0-6.5	2.0-5.0	1400-3500
Peppers	5.8-6.3	1.8-2.8	1400-2000
Pineapple	5.5-6.0	2.0-2.4	1400-1680
Potato	5.0-6.0	2.0-2.5	1400-1750
Pumpkin	5.5-7.5	1.8-2.4	1260-1680
Radish	6.0-7.0	1.6-2.2	840-1540
Red Currant	6	1.4-1.8	980-1260
Rhubarb	5.0- 6.0	1.6-2.0	840-1400
Rosemary	5.5-6.0	1.0-1.6	700-1120
Roses	5.5-6.0	1.5-2.5	1050-1750
Sage	5.5-6.5	1.0-1.6	700-1120
Silverbeet	6.0-7.0	1.8-2.3	1260-1610
Spinach	5.5-6.6	1.8-2.3	1260-1610
Squash	5.0-6.5	1.8-2.4	1260-1680
Strawberries	5.5-6.5	1.8-2.2	1260-1540
Sweet Corn	6	1.6-2.4	840-1680
Sweet Potato	5.5-6.0	2.0-2.5	1400-1750
Swiss Chard	6.0 6.5	1.8-2.3	1260-1610
Taro	5.0-5.5	2.5-3.0	1750-2100
Thyme	5.5-7.0	0.8-1.6	560-1120
Tomato	5.5-6.5	2.0-5.0	1400-3500
Turnip	6.0-6.5	1.8-2.4	1260-1680
Watercress	6.5-6.8	0.4-1.8	280-1260
Watermelon	5.8	1.5-2.4	1260-1680
Zucchini	6	1.8-2.4	1260-1680

EC to ppm Conversion Chart

There are different conversion factors for the different Manufacturers (Hanna, Eutech and Bluelab Truncheon)

Jun32018 by lm3 Comments

A quick guide on vegetative propagation and how to make the most of your cuttings

Vegetative propagation is a form of asexual plant reproduction that can take place in both wild and cultivated environments. Methods of vegetative propagation include cutting, layering, grafting, and tissue culture.

Advantages

Well suited for growing in stable or controlled environments
Uses less resources such as water or nutrients
Reproduction requires only one plant
Produces “offspring” more frequently
Beneficial traits are passed on
Desirable sets of characteristics are passed on season to season

Disadvantages

Lack of genetic variability
Lack of seed production will limit plants’ ability to spread or be “stored”
Harmful traits are passed on
Plant pathogens are more easily transferred to new environments

Food plants commonly cultivated with vegetative propagation

Basil
Strawberry
Blackberry
Mint
Watercress

Pineapple
Sugar cane
Vanilla
Sage
Lavender

Cloning/Cutting

Layering

Grafting

Tissue Culture

Tips for taking great cuttings

Use clean, sharp scissors, shears, razors etc.
Always cut right beneath the nodes at a 45 degree angle
For most plants a 4 to 6 inch long cutting will be appropriate
Remove between 1/3 to 2/3 of the leaf matter and side branches beginning at the “cut” while working your way up
Have a temporary cup of water to place individual cuttings in prior to planting or plant each cutting immediately when taken
Select a rooting medium that is appropriate for the growing environment your cutting will be placed in
For “woody” type plants such as basil or lavender the most successful cuttings will always be branches taken from the main stem with cuts made in close proximity to the main stem
Stay positive and remember to take more cuttings than you need as a percentage of them will not always root