Building a System
This page displays detailed information about growing vegetables in a shade house in Perth Western Australia. The shade house measures 10 metres long by eight metres wide and is covered in 30% white shade cloth, with a second roll out ceiling installed for use in the summer to reduce glare from the sun.
The shade house will also be covered with horticultural clear film located immediately below the roof shade cloth and inside the walls of the fully enclose shade house. The shade house will have opening vents in the walls and roof that can be activated to ventilate the shade house during summer, and closed during winter to help retain heat. Bees will be introduced to the shade house via a suitably located beehive positioned to provide the bees with access to both the interior and exterior of the shade house.
Optimal soil and atmospheric conditions for year round growth of plants inside the shade house need to be identified for this geographic location, including the following: Light levels for different times of the year, soil and air temperatures for various types of fruit and vegetable plants, soil moisture levels, soil minerals, air carbon levels, fertilization using fish waste, circulation of water through the system to enable surplus water drained from the grow beds to be used for the raising of edible fish kept in a suitable tank or pond. These details will no doubt be different for an enclosure located in a different geographic location and at a different elevation, although the overall concepts will be similar.
Optimal Soil and Atmospheric Conditions for Year-Round Growth of Plants in the Shade house
The amount of light that reaches the plants will depend on the type of shade cloth used, the time of year, and the weather conditions, plus the specific location of the enclosure relative to other buildings and trees etc. In Perth, the average light intensity ranges from 10,000 to 15,000 lux in the summer (December to March) and 5,000 to 10,000 lux in the winter (June to September).
Most vegetables and fruit plants require at least 6 hours of direct sunlight per day. However, some plants, such as leafy greens and root vegetables, can tolerate less light. If you are growing plants in a shade house, you will need to choose varieties that are tolerant of lower light levels, or alternatively, install suitable equipment to provide additional lighting and heat during the winter months.
Soil and Air Temperatures
The optimal soil temperature for most vegetables and fruit plants is between 15 and 25 degrees Celsius. The air temperature should be between 18 and 28 degrees Celsius.
In Perth, the average soil temperature ranges from 10 to 20 degrees Celsius in the winter and 20 to 30 degrees Celsius in the summer. The average air temperature ranges from 12 to 22 degrees Celsius in the winter and 22 to 32 degrees Celsius in the summer. All of these figures will be different for different geographic locations.
If you are growing plants in a shade house, you can help to regulate the temperature by using fans, heaters, and vents.
Soil Moisture Levels
The optimal soil moisture level for most vegetables and fruit plants is between 60% and 80%. The soil should be moist, but not soggy. In Perth, the average rainfall is 850mm per year. However, the rainfall in this location is unevenly distributed throughout the year, with most of the rain falling during the winter months. If you are growing plants in a shade house, you will need to water your plants regularly, especially during hot summer months. You can use a moisture meter to check the soil moisture levels.
Vegetables and fruit plants need a variety of minerals to grow healthy and to produce fruit. The most important minerals are nitrogen, phosphorus, and potassium.
You can improve the mineral content of your soil by adding compost, manure, or fertilizer. You can also have your soil tested to determine which minerals are lacking. Be cautious about adding too much or too little manure and too much or too little water. Obtain a suitable meter that measures light, Ph and moisture, and lean how to adjust these three items to achieve optimal levels. Also, obtain a suitable greenhouse thermostat, so that you can monitor and adjust temperatures and ventilation as required to help you achieve optimal growth rates for the different species of plants.
Air Carbon Levels
Plants need carbon dioxide to grow. The optimal carbon dioxide level for most vegetables and fruit plants is between 300 and 400 ppm. In Perth, the average carbon dioxide level is around 400 ppm. However, the carbon dioxide level can drop below 300 ppm in a closed environment, such as a shade house. If you are growing plants in a shade house, you can increase the carbon dioxide level by using a carbon dioxide generator or by adjusting the ventilation levels with in the shade house.
Fertilization Using Fish Waste
Fish waste is a good source of nitrogen, phosphorus, and potassium. It can be used to fertilize vegetables and fruit plants.
To use fish waste as fertilizer, you need to compost it first. This will kill any harmful bacteria and make the nutrients more readily available to the plants.
Once the fish waste is composted, you can add it to the soil or use it to make a liquid fertilizer.
Circulation of Water Through the System
You can circulate water through your shade house system to water your plants and raise fish.
To do this, you will need a water pump, a reservoir, and a system of pipes and hoses. You can also add a filter to the system to help keep the water clean.
To water your plants, you can connect the pipes and hoses to drip irrigation emitters or sprinklers. To raise fish, you can connect the pipes and hoses to a fish tank or pond.
By following the tips shown above, you can create optimal soil and atmospheric conditions for year-round growth of plants in a shade house.
• Choose plants that are suited to the climate in Perth and the amount of light available in your shade house.
• Test your soil regularly and add compost, manure, or fertilizer as needed.
• Water your plants regularly, especially during the summer months.
• Monitor the temperature and humidity in your shade house and make adjustments as needed.
• Fertilize your plants using fish waste or other organic fertilizers.
• Circulate water through your shade house system to water your plants and raise fish.
Fish Tank and Pond
The following describes how to economically build a fish tank for the shade house, possibly using the ferro-cement system that is used for building water tanks. The tank will need to be a suitable size for the 80 square metre shade house. There is also a large unused swimming pool that can possibly be turned into a fish pond using a suitable plastic liner. This pond could possibly be used to raise even more fish if required.
The pond measures about 8 metres long by 6 metres wide, and has an average depth of about 1.6 metres. Part of the pond has space for a natural filtration system, plus plants can be grown on floating islands in the pond and in baskets hanging from the pond side-walls.
Ferro Cement Fish Tank
Ferrocement is a type of rendered concrete that is reinforced with wire mesh. It is a strong and durable material that is well-suited for building fish tanks.
To build a ferrocement fish tank, you will need the following materials:
• Wire mesh
• A mold for the tank is also a possibility
Start by making a suitable wire frame and mold for the tank. The mold can possibly be made out of wood, metal, plastic, or old sheets of fencing material.
Once the mold is complete, place rebar supports and cover it with wire mesh. The wire mesh should be strong enough to support the weight of the concrete.
There are multiple YouTube videos that describe the construction of ferro-cement water tanks.
Next, mix the cement, sand, and water together in the recommended proportions to form a suitable concrete mixture. The concrete mixture should be thick enough to easily coat the wire mesh. The concrete could possibly contain a suitable waterproofing agent such as Dampco, and once set the concrete or cement can be coated on the inside with a suitable pond lining paint, or even with a suitable plastic pond liner. Also, by painting the outside walls of the tank black or by using a black coloring agent in the concrete mix, the tanks will act as a heat collection and storage tank. Line the outside of the shaded side of the tank with a suitable insulation material in order to retain as much heat as possible and to help reduce heat loss, although night time heat loss on the sun facing side of the tank may possibly be an issue, and may require some form of insulation. Multiple solutions to this issue could be designed, such as insulating the entire tank and then placing solar panels on the sunny side of the tank and roof. Although leaving space for an access hatch so that you can access the fish in order to catch them.
Pour the concrete mixture into the mold or/and trowel it onto the wire frame, and allow it to cure for at least 24 hours.
Once the concrete is cured, remove the mold and fill the tank with water.
Swimming Pool Fish Pond
You can convert your unused swimming pool into a fish pond by using a suitable plastic liner.
To do this, you will need the following materials:
• A plastic liner
• A filter system
• A pump
• An aeration system
To convert the pool into a pond, start by cleaning the pool thoroughly.
Once the pool is clean, line it with the plastic liner. The plastic liner should be large enough to cover the entire pool, including the walls and floor. Ensure that there are no leaks in the liner or in the connecting pipework.
Next, install the filter system, pump, and aeration system.
Finally, fill the pond with water and add your fish.
Making the System Efficient and Economical
Here are some suggestions to make the entire pond, fish tank, and shade house as efficient and as economical to construct and operate as possible:
• Use recycled materials whenever possible. For example, you could use recycled tires to build a raised bed for your plants in the shade house.
• Use solar power to operate the pump and aeration system for the fish pond.
• Collect rainwater to water your plants and fill the fish pond and fish tank.
• Plant fast-growing plants as may be required to help provide shade for your fish pond.
• Use a natural filtration system for your fish pond.
• Grow your own fish food, such as worms and crickets.
By following these tips, you can create an efficient and economical pond, fish tank, and shade house growing system.
How many people would such a system potentially be capable of feeding?
The number of people that a pond, fish tank, and shade house system could potentially feed would depend on a number of factors, including:
• The size of the pond and fish tank
• The number and type of fish being raised
• The amount of food the fish are eating
• The growth rate of the fish
• The amount of food produced in the shade house. For example, wast from growing vegetables, could be used to create a compost are in which worms could be raised
According to the Food and Agriculture Organization of the United Nations, the average global per capita consumption of fish is around 20 kilograms per year. So if you plan on raising say 100 fish, you will need to create 2000 Kilos of fish food, although you could purchase some fish food to supplement your own production.
A well-managed pond, fish tank, and shade house system could potentially feed a family of four with few external inputs once your system is built. However, if you are planning to raise a large number of fish or to grow a lot of food in the shade house, you may be able to feed even more people.
Do your own calculation regarding how much it costs to feed each individual for one year and multiply that number by the number of individuals in your family. Then calculate the costs associated with building a suitable system to see how long it will take to recover the initial expenditure. You will hen know the value of developing your system, and will know how long it will take o recover your initial investment.
Here are some tips for maximizing the number of people that your system can feed:
• Choose fish that are known to grow quickly in your location and are efficient at converting food into good quality edible flesh.
• Feed your fish a high-quality diet.
• Harvest your fish when they are at their peak weight.
• Grow vegetables and fruits that are high in nutrients and are easy to store.
• Preserve your food by canning, freezing, or drying it.
By following these tips, you can create a system that can economically provide food for your family and friends year after year.
Getting your system to operate at peak performance can only be done through experimentation and trial. Keeping relevant records will help you to see the progress you make, and will over time help you to make appropriate adjustments to the system.