Production Record

The following table records how much vegetable we produced at 248x52 greenhouse.

Dates	Productions	Note
8/28/11	13 totes minis and long English.
8/29/11	14 totes minis, 1 tote grape tomatoes.
8/30/11	13 totes minis and long English.
8/31/11	17 totes minis and long English, 3 totes grape tomatoes.
9/1/11	data lost
9/2/11	13 totes minis, 1.5 totes long English.
9/3/11	17 totes minis.
9/4/11	16 totes minis.
9/5/11	21 totes minis, 3 totes long English.	from sunny week
9/6/11	21 totes minis.
9/7/11	20 totes minis, 3 totes long English.
9/8/11	24 totes minis.
9/9/11	24 totes minis.
9/10/11	22 totes minis.
9/11/11	17 totes minis.
9/12/11	18 totes minis, 9.5 totes long English.
9/13/11	16 totes minis.
9/14/11	16 totes minis.
9/15/11	12 totes minis, 15 totes long English.
9/16/11	6 totes minis.	plants getting old, cloudy days
9/17/11	9 totes minis.
9/18/11	9 totes minis.
9/19/11	11 totes minis.
9/20/11	10 totes minis, 6 totes long English.
9/21/11	12 totes minis.
9/23/11	13 totes minis.
9/26/11	10 totes minis, 8 totes long English.
9/28/11	6 totes minis.
9/29/11	6 totes minis, 6 totes long English.

Quick Reference:

• Full tote of minis - about 18.5kg
• Full box of minis - about 20kg
• Full tote of grapes - about 27kg

Spraying for Mildew

  It seems that some chemicals need to be approved before being used in a greenhouse, such as one for spraying mildew.  Pristine was just being used at 248 on the cucumber plants.

Carl adjusting the intensity of the spray.

  The solution mixture ratio is 40 grams per 100 liter of water.  We will add more if the mildew condition is really bad.  Some chemicals are also known to kill mildew and spidermites as well, but they may be illegal to use.  Mildew is easily killed, as just water itself can pop their spores.  We use Pristine because it stays and continually kills the spores when they pop out.

  According to Carl, to find out if the mildew infection is gone after spraying, we check the mildew spots after three days to check for the presence of brown spots instead of white spots. We usually just spray on top of the plants, but we can also spray from the bottom and then the top for more protection.

Carl spraying from below the leaves.

Carl going backwards and spraying the top of the leaves.

Carl spraying the walkway in the end.

  Currently we buy 1.8 liter Pristine for $800.

Daily Routine

Daily work done by workers.

Dates	Mark	Kyra	Yucho	Johnston
9/15/11 Thursday	Picked minis and longs, packing.	Lowered minis, picked up grape tomatoes on floor.	Clean out the TOVs.	Clean out the TOVs.
9/16/11 Friday	-	-	Went to Marom; Mixed fertilizers, learned about the water system.	Went to Marom; Mixed fertilizers, learned about the water system.
9/17/11 Saturday	Picked minis, packing, and clean out dead tomato trees.	-	Clean out the TOVs.	Clean out the TOVs.
9/19/11 Monday	-	-	Went to Marom; Mixed fertilizers, learned about buffer, looked at phase 1.	Went to Marom; Mixed fertilizers, learned about buffer, looked at phase 1.
9/20/11 Tuesday	Picked minis and longs, packing.	Lowered plants and prune minis.	Pruned minis.	Pruned minis.
9/21/11 Wednesday	Picked minis, packing.	Walking around, twiddling, checking plants for fungus/parasites.	Disposed tomatoes/plants.	Disposed tomatoes/plants.
9/22/11 Thursday	??	At Chiliwhack. Cut down and removed cucumber plants from greenhouse.	At Chiliwhack. Cut down tomato plants and pile them neatly.	At Chiliwhack. Cut down cucumber plants from greenhouse, removed plastic around plant blocks.
9/23/11 Friday	Absent.	Picked minis.	Absent.	Picked minis, twiddled.
9/24/11 Saturday	Picked minis.	-	Picked minis, twiddled, cleaned tomatoes.	Picked minis, twiddled, cleaned tomatoes.
9/25/11 Sunday	Absent.	Picked minis, cleaned up tomato plants.	Picked minis, cleaned up tomato plants.
9/26/11 Monday	-	@ Chiliwack, cleaned up tomatoes and cucumber plants.	@ Chiliwack, cleaned up tomatoes and cucumber plants.	@ Chiliwack, cleaned up tomatoes and cucumber plants.

Removing Plants in Chilliwack

  In Chilliwack greenhouse, plant removal process is much more organized than 248.  This way, it saves much of the labor cost.  The key to easier and cheaper removal of the plants is one step at a time.

  If we have an advanced facility like Merom, we could apply the same cleaning procedure for bell peppers to tomatoes.  But we don't in Chilliwack, so we do the cleaning one step at a time.  We start by first clipping the stems at the root.  We let the plants hang and dry for a day.  Then we cut the strings to drop the plants, but instead of collecting the strings like we did in 248, we let the strings hang on to the steel wire.  This saves labor for the workers to walk around and collect the strings on the floor, which are often overlooked and thrown away with plants.  After the plants are on the floor, we pile them strictly in between the pipes.  We cut off any part of plants that connects to any other place.  So in the end, we will have one long pile in between the pipes.  Finally, we will cut the long pile at some adequate distance (3 or 4 steel column is about right), and use 3 people to hold the front, middle, and back, and carry the pile outside to the garbage bin.  It is similar to how people carry the Chinese dragon in festivals.

UPDATE 1:   It seems that the plants did not get tangled and stacked enough to be done.  Plants would be sag while being carried, so each of us just carried 3-5 plants out at once instead of 2-3 person carrying 4-6. 

  Removing cucumber plants is somewhat simpler than tomatoes because of the way we grew them in Chilliwack.  If we grew the cucumbers the same way we did tomatoes (i.e. lowering the plants until they die), then the cleaning process would be the same.  But we, instead of lowering, threw the plants over the steel wire and let them grew downward.  So the cleaning process is somewhat simpler because the plants are not as tall as the tomatoes.  What we do is, as with tomatoes, cut the stem at the root first.  Then we cut the strings off, and make sure that any string knots will have to come off the steel wire to prevent disease carry-over to next generation of plants (note that we tied strings on the wire instead of hanging down rolls of strings because we didn't lower plants).  As we cut the strings, we stack the plants neatly in separated piles.  After all the plants came off the steel wire, we carry the piles out to the garbage bin.

  Cleaning procedures in Chilliwack was much easier than 248, and we learned that efficient process is very important to keep workers motivated and save costs.

Lowering Cucumber Plants

Lowered cucumber plants.

 Lowering is one technique to prolong the production life of the plants.  Because crops mature and get harvested from the bottom, we lower the plant to make the stems sit on steel wires that are shown below.

An example placement of steel wires where the plants
can rest their stems.

Once the crops are harvested at the bottom, we trim everything off including suckers, leaves, and cucumbers up to certain height to make the plants sit on the wires.  Eventually we curve the stems back and forth when they are too long, so they look kind of like snakes sitting.

This technique is more organized than hanging the plants and letting them grow downward.  It is also long-lasting because the latter method can only let the plants grow until it makes a round trip to the floor.  But Kyra and I doubt the efficiency of this technique because the longer the stems, the longer the distance the nutrients travel upward from the roots.  We need to verify that keeping the plants grow in one long stem and concentrating everything on top is actually worth the effort.

UPDATE 1: Note that we either use this technique or we use clippers and horizontal wires to support the mature plants.  Kyra has mentioned that we get more production from lowering plants than using clippers and horizontal wires.

UPDATE 2: Carl has mentioned that we used clippers and horizontal wires because it was easier for the workers to support the plants with. If we were to lower the plants instead, we have to do it every 2-3 days. Lowering also gives more production, and the height does not matter for the nutrients that are traveling up.

Powdery Mildew

Severe powdery mildew conditions on leaves.

Powdery mildew is the dusty white coating that appears on the top of the leaves surfaces and are usually circular.  They appear in humid and warm conditions, such as densely growing plants.  They are able to withstand really cold days during winter and release their spores during spring.  They spread by wind or contact with infected plant materials.

The fungus can stunt the growth of plants, and usually kills the leaves - the leaves turn yellow and drop from the plant.  They suck up nutrients from the plant, so this causes a decline in growth in the production of the crops.

To control this fungus, we can remove the leaves if detected early.  Pruning overcrowded plants can help air circulation, which in turns reduces humidity.  Spraying of chemicals help as well, but it is more important to dispose of the infected leaves properly and not leave them on the floor.  Chemicals that can be used includes baking soda solution or lime-sulfur.

Source:
http://www.caes.uga.edu/extension/cobb/anr/Documents/Powdery.pdf

Worker Motivation

  As an important step for management, we need to motivate the workers to produce the best output.  The most direct way is compensation because physical laborers tend to be money-driven (since there is no other job satisfaction factor).  Last year, Merom farm compensated the pickers a penny for every kilogram they picked.  So scales were located in the greenhouse, and pickers weighed their bin whenever they finished their rows.  Carl said this idea was stupid because the measuring process was a huge waste of time, which is imaginable because there must be some sort of oversight to prevent cheating.  Since the beginning of this year, Ranjit, the HR guy in Merom keeps track of three levels of workers: fast, medium, and slow.  Each type of workers get equal wage, but the bonus at the end of the year differs by the level.

  The latter compensation system works much better than the former, but workers' compensation in the latter system depends on the HR's judgement, which can very well be biased.  We will brainstorm more ideas on worker motivation program to ensure motivated workers that can result in optimum profit.

  As a miscellaneous info, one girl last year got compensated some amount between $140,000 ~ $160,000.  This means she picked 140-160 tonnes last year.  Say she picked 150 tonnes, then she would had had to pick 150,000 / 365 = 410kg everyday.  That's a lot of bell peppers for a single worker, and there are about 13 pickers in 15 acre of land (and 19 more pruners).  It only gets exciting when you do the math for the total production in weight per day per the entire greenhouse...

Aphid

Magnified picture of live aphids.

Corpses of aphids (white ones) on bell pepper leaves.

  Aphid is a sap sucking insect that is destructive to many of cultivated plants.  In our case, cucumbers, tomatoes, and bell peppers all suffer aphid infestation.  In Merom, Carl mixed chemical in the fertilizer tank that, upon absorption by plants, kills aphids when aphids suck on phloem.  On the other hand, he used Aphidius ervi, a biopesticide solution in the 248 greenhouse.

  Biopesticide is generally a better solution than chemical pesticides because it is less stressful to plants.  Some chemical pesticides may affect workers' health and require license to spray, but bugs are harmless.  The downside of biopesticide is the cost.  Not only product itself is more costly than the chemical pesticide, but also the application takes labor.  For example, we need to use several workers to spread the bottle bugs equally in the greenhouse, whereas we can simply mix the chemical pesticides in the fertilizer (except for the spraying type).

Importance of Space and other Needs for Plants

  From what Carl has taught us about understanding the plants' needs, we need to imagine and to relate ourselves to plants:  If we are a plant in a greenhouse, what would we need?  For example, there will be weeks of hot weather during summer, and how would we know if the greenhouse is too hot?  The answer is simple: If we, the workers in the greenhouse, can feel the heat and the need to cool down and drink more water, the plants will need to as well.

  As silly as it may sound initially, treating plants as someone like us is easier for us to understand their needs.  Space for plants must not be neglected - cramming too many plants per square meter will result in plants not getting enough sunlight in the future.  We all want huge output,but 2.5 - 2.6 plants per meter squared seems to be the recommended density.

  Plants do get stressed out as well.  According to Kyra, when the weather gets very hot, ~27 degrees celcius and above, plants are usually stressing at that point.  If we pick or prune or twiddle when the plants are stressing, it usually results in the plants "giving up" and they end up not producing anymore output.  This is important to note, and it is the reason why workers do not usually do anything with the plants after 2pm, which is when it gets really hot.

  Plants also need sufficient space above them called buffer.  Note the picture below:  The space above the plants' heads to the beams supporting the roof is the buffer zone.  Buffers are important for the air to mix inside the greenhouse for stable and equal temperature and heat throughout the greenhouse, which is aided by fans hanging above the plants.  The larger the buffer, the better it is for the plants.  For example, tomatoes need huge buffers to prevent their heads from overheating and killing the plant since they grow very tall. 

Poly sheets covering that is used for protecting against
scorching sunny days or containing the heat
inside the greenhouse during cold weathers.

  Notice the sheets that is being dragged slowly to the right.  This poly sheet wears out every 2 years and needs to be replaced.  It protects the greenhouse from heavy sun rays and also prevents the heat from leaving the greenhouse during cold days. 

More sheets at the side, but this is always there and
only replaced and taken down during clean up.
Note the generous buffer zone for the plants.

Fertilizer in Merom

  Fertilizer is one of the most important aspect of greenhouse operation.  Plants draw most of their necessary energy from the Sun in the form of photosynthesis, but they still need certain kinds of minerals to grow.  According to Carl, the recipe differs by location of the greenhouse because the climate and sunlight level are different.  And of course, the recipe differs completely among different variety of plants.  The list below shows the current recipe Carl uses for the bell peppers in Merom:

Tank A:

Ingredients	Amounts
Calcium Nitrate (liquid Ca)	2 container (1390kg * 2)
Potassium Nitrate (KNO3)	16 bags (25kg * 16)
Iron (liquid Fe)	4 buckets (= 64 bags 25kg solid Fe)

Tank B:

Ingredients	Amounts
Epsom Salt (MgSO4)*7H2O (Magnesium Sulfate, Heptahydrate)	21 bags (25kg * 21)
Potassium Nitrate (KNO3)	8 bags (25kg * 8)
Manganese	1500g
Zinc	3000g
Boron	4200g
Copper	600g
Potassium Chloride	2 bags (25kg * 2)

  There are 4 tanks of fertilizer mix, A1, A2, B1, and B2.  We refill and mix A1 and B1 while A2 and B2 are in use for irrigation.  When A2 and B2 run out, we refill and mix them while using A1 and B1 for irrigation.  We do this (1) to keep the fertilizer up and ready the whole time and (2) because fertilizers take a day of mingle to fully dissolve in the tank.  The four tanks can contain over 4000 liters, and the recipe above is calculated to, after dissolved in water, produce 4000 liter of mixture.

Tank A1 with Iron.

Tank B2 with Potash.

  The reason why we separate tank is that calcium and iron are better not mixed with Epsom salt in high concentration.  When they do, they form a solid precipitation that is hard to dissolve in water.  If the concentration is low, the precipitation does not occur; that's why we mix them together with water at the merge point.

  Note that no ingredient in the recipe above is 100% pure.  For instance, potassium nitrate we use is composed of, according to the minimum guaranteed analysis, 13.7% nitrate nitrogen (N-NO₃), 38.4% K, and 46.3% K₂O.  The detail of each ingredient will be added.

  Also, it is good to know that the cost of fertilizer is about $5,000 for single A and B tanks.  In summer, we mix the fertilizers about 4-5 times per week.  All other seasons we do it about twice a week.  So in summer, it costs about $25,000 a week just to prepare the food for the plants.  Wow, they better produce the darn crops!

Irrigation in Merom

3 tanks containing water.

  There are 3 tanks containing enough water for 2 days in case of an emergency water cut off.  One tank contains returned water after irrigation (Carl calls it recert).  The other two contains a mixture of rain, city, and well water.  Well water this year contains high level of sodium, so we use Phosphoric acid during the fertilizer mixing process to lower the pH level before irrigating plants.

One of the filter pump stations.

  There are also 8 tanks of filter pumps that the mixed water with fertilizer goes through before heading to the plants.  These tanks contain filter sand that gets rid of tiny garbage that may clog the pipes.  The garbage could be weeds growing on the water, piece of construction material that went in the fertilizer tank, and so on.  The filter sand is replaced every year in the cleaning season (December).

Filter sand stock.

  The pure water and recert water merge at one point in the pipe.  Then the machine that monitors both the pH level of mixed water and the fertilizer draws just the right amount from the two to make the perfect mix for irrigation.  The perfect mix is stored in the large tank located in the irrigation room and sent off to the plants every so often.  Of course, the frequency and duration of irrigation depend on temperature, climate, plant conditions, and many other factors.

  

  We also have to occasionally clean out the tanks since weed will grow on the surface.

Dried sand-like weed that is thrown out from
the water tank.
They look very green and moldy in the tanks.

Weed in a tank of water already mixed with fertilizers.

  It is important to note that recert water from certain plants cannot be immediately reused to water certain plants.  For example, excess water used for watering tomato plants must not be used to water tomato plants again because there might be viruses from the plants that got into the recollection sewer.  According to Carl, a sterilizing system is the better choice to counter this problem since the payback is 3 years compare to just wasting water.  The sterilization can be done in multiple ways, one of which is ultraviolet radiation.  The following are some of the water we can and can't reuse for.

• Bell pepper water can be reused to water bell pepper
• Cucumber water can't be reused to water cucumber
• Tomato water can't be reused to water tomato
• Cucumber water can be reused to water tomato
• Tomato water can be reused to water cucumber

  For more information about how the fertilizer is prepared, refer to the Fertilizer in Merom. (hyperlink to be added)

Stem Rot Disease

Several of the plants in 248 greenhouse are affected by stem rot disease.  The disease is fatal to the plants because once the plants gets it, they will die.  The bacteria grow in the stem to rot the stem, hence the name stem rot.  The disease is highly contagious, so it must be treated with care.  For instance, when removing the infected plants, we don't want to touch any other plants besides the infected ones, which may risk the epidemic of stem rot.

Water System for a Greenhouse

Currently at Merom, there is one giant big tank outside the facility for hot water circulation. The water is heated in the boiler room using natural gas instead of the wood burner since it's more cost efficient.  That tank is part of the enclosed heating system for the entire facility, including phase 1, 2 and 3. All the water is circulated, and the tank contains sensors for both the temperature and the water level. If the water level is below a certain level, alarm will notify the facility. The tank also contains 9 temperature sensors, making sure the water is not boiling but kept at a relatively high temperature, around 92-98 Celcius.The water must not boil since it's an enclosed system and the air is not pressurized in the tank.

Hot Water Tank

If the water level drops below a certain level, then we know there is a leakage somewhere in the system since everything is enclosed and all water does not escape. Natural gas is used to heat up the water, and it mixes with cold water in a mixing valve to obtain the desire temperature before sending the water off to the heating pipes to heat up the greenhouse.

Cutting Leaves Off

Cutting the leaves off for Kasja, a variety of long English is pretty much the same task as doing so for minis.  Today, we cut the leaves off to about my chest height so that we could continue to lower the plants.  We lower the plants to allocate more space for the heads to grow.  But the long English plants are already old (roughly 3 months) and are not producing as much as when they were young.  Also, stem rot disease is spreading and more than 15 plants are withered.

That being said, I doubt the effectiveness of today's operation.  According to Kyra, we want plant energy to concentrate on top and therefore trim off excess parts from the plants up to certain height.  But leaves are the producer of the energy, and to trim them off means to cut short the energy supply.  In order to verify the sanity of this action, I would have to investigate further.

Trimmed naked up to chest height.

As we trim, we also look for crooked, molded, and any defective cucumbers to get rid of.  We also get rid of other junks like suckers at the root.

Priva Maximizer

Priva Maximizer is the control system we use in 248x52 greenhouse.  Priva Maximizer automates important controls in the greenhouse to save our time.  We can access the system through two user interfaces: buttons and display on the Priva Maximizer and a PC display.

The buttons and display on Priva Maximizer.

There are six sets of wires that transmits the control signals across the greenhouse.  Each set partakes different set of inputs/outputs to specific zones in the greenhouse.

The bottom part of Priva Maximizer.
You can see the six pink wires sticking out.

The six wires coming out from the office.

The wires splitting.  Two go right, four go left.

The two wires to the right go to irrigation control and boiler room.  At the irrigation, the system opens/closes pipes that convey water (with fertilizer mix) to the plants.  The amount of fertilizer mix that is pumped to the pipe is also controlled by Priva Maximizer.  The system keeps track of flow direction to prevent backwash system.  For further information, refer to the Priva Maximizer operation manual.

The thick pink wire (right) coming in to the irrigation
control.  The thinner wires (left) go to irrigation valve
and other control (e.g. fertilizer pulse).

Control signal sent to irrigation valve.  When the valve
is opened, water flows to the plants.

A complex control box for I-dunno-what.

Pulses of fertilizer from the tube are mixed to the
irrigation pipe.

In the boiler room, the control signal controls the heating of the greenhouse.  Unfortunately we are not heating the greenhouse at all because, according to Carl, the greenhouse is not making enough money and thus not worth heating.  I don't know the electricity expense to crop output ratio, but I think it is a waste of investment.

The wire incoming to the boiler room control box.

A closer look to the control box.

Another closer look.

Thin pink wires coming from the control box to control
the amount of boiled water sent to heat the greenhouse.

Bottom part of the boiler.

A closer look.

Going back to the remaining four wires, one of them goes to the antenna located on top of the greenhouse.

Pink wire receiving data from the antenna.

The antenna has five visible sensors attached.  I will explain the detail of each sensor, but I am not entirely confident about the correctness.  The farthest right is the wind direction sensor, where the sensor is supposed to be calibrated (pointed) to the north.  In the picture, however, the sensor is pointing southeast and I need to verify why.  The farthest left, a Mickey-mouse-like spinney blade, is a wind speed sensor.  The second from the left is an aspirated temperature/humidity sensor.  The two remaining similar ones are rain and sunlight sensors.  I hope I'm right.

The remaining three wires split, one to the small
and two to the big greenhouse.

A control wire to the control box in the small greenhouse.

A motor that controls the ventilation. 

A burner that supplies CO₂.

A control box of I-dunno-what.

An aspirated temperature/humidity sensor.  This is
located in multiple locations.

We are not utilizing all the functions provided by the Priva Maximizer.  For example, we can't use burner to supply CO2 to the plants.  We don't heat up the greenhouse to stimulate the plant growth.  Maybe it is costly, maybe it is just cumbersome, but that's the current policy of Carl.

Harvesting Long English

A perfect long English for harvest.

Harvesting long English is not much different from harvesting minis.  The only difference is that we allow the cucumbers to grow for longer period, so we harvest every other day instead of everyday.  We need to make sure that crooked and funny looking ones must also be cut off because they will turn out as garbage for sure.

As with minis, the flowers on long English must also be torn off because the flower will rot and so will the cucumber.  If the flower on long English is torn off when still on vine, the cucumber will no longer grow.  So that cucumber must also be cut off and thrown away.

Example of a bad cucumber that must be cut off.

The Greenhouse Structure And the Fertilizers

Current greenhouse is relatively small by size.  It features two front entrances: a normal door and two sliding doors.  There's also two sliding doors in the back of the greenhouse which is used for dumping bad crops and trimmed plants.

The greenhouse currently uses three fertilizers: Magnesium Sulphate, Potassium Nitrate, and Calcium Nitrate.

Four buckets containing mixture ratios of fertilizers.

Huge tanks containing water.

Steel wires are hung across the greenhouses from
one end to the other for the strings' supports.

The sliding doors at the back of the greenhouse
for dumping bad crops and pruned materials.

The unused entrance.

Carl usually opens these sliding doors and move
his truck here for picking up/dropping off totes.

Two unused offices.  One of them contains the computer
system governing all the
water supply/window opening mechanisms.

Heating pipes which also work as railings.

Pipes protrude onto the cement floor
for easier cart maneuvering onto the pipes.

Steel chains supporting more
steel wires for the strings supports.

Some strings don't need chains; they are
supported by the beams of the structure.

Collected strings from fallen plants.

Basic cart and totes.