Mutli-Phase Humboldt MCU Garden Project

As yesterday's Humboldt Laser Harp post indicated, the microcontroller (MCU) music group project is well under way. So now I'm thinking about how to get the second group project started in the Humboldt Microcontrollers Group, one involving gardening.

MCU and sensors for potted plant

Several people who've been at Humboldt Makers Group meetings or the MCU group meetings have said they're interested in MCUs and gardening. And it seems like lots of other people in Humboldt County might have an interest in ways to improve gardening. There are lots of organic gardeners in the area, and agriculture has been part of the Humboldt economy for much of the area's history. So I've decided to outline a multi-phase approach to a collaborative project focused on MCU gardening. And a significant part of this collaborative project will be identifying and reaching out to Humboldt people who are involved in gardening or agriculture and might be interested in sharing their knowledge and / or participating in this project.

MCU and hydroponics

Two long term goals I have for the MCU gardening is to be involved with a successful hydroponics system and a successful aquaponics system. There are lots of websites and projects on the Internet that tell a person how to do hydroponics or aquaponics, but I'm an engineer, and I like to understand what I'm doing. Plus I don't have a lot of money to spend on these projects. So my preferred approach to MCU gardening is to start out small, and get more complex after I understand the technology and 'green thumb art' involved with each part of the MCU garden project.

Below are proposed MCU garden project phases. If we get the right people involved with the project and if we can secure funding of some type for the project, we can move very quickly through the phases or work on more than one phase at a time. So if you know people who'd like to participate in this project or know of money that can be used for purchasing electronic components and supplies for this, please contact me at arcatabob (at) gmail {dott} com. These are the proposed phases for the Humboldt MCU Garden group project:

MCU and aquaponics (from dzbc.org.cn)

1. Grow one plant indoor in soil.
2. Grow four to eight plants indoor in soil.
3. Grow four types of plants outdoor in soil.
4. Grow one 'tray' of plants indoors in hydroponic system.
5. Grow three types of plants indoors in hydroponic system.
6. Grow one type of plant in aquaponics system.
7. Grow three types of plants in aquaponics system.

Phase 1 of the Humboldt MCU Garden project is simple and low cost and will help us learn the basic principles of MCU gardening. Phases 2 through 7 can easily be redefined as we get more people involved in the project and we learn more about what we don't know about MCU gardening.

The first draft design of the Humboldt MCU Garden project includes:

1. One type of plant.

   

   LEDs and lettuce

1. Lettuce is my first choice, partly because of what's being done with optimized lettuce 'mcu gardening' in Japan and other places (see my blog post "LED Lettuce, The HydroTower And LED Humboldt Hydroponics.") We might be able to find useful data about optimum growing conditions for lettuce (light wavelengths, relative humidity, nutrients, temperature, etc.).
2. If other people who want to participate in the Humboldt MCU Garden project prefer to grow something other than lettuce and have information about good growing conditions for that plant, I'm willing to switch from lettuce.
2. Growing container.
1. The type of growing container probably won't be too critical for Phase 1. Mainly something large enough to hold the soil and drainage system that will provide good growing conditions for the plant.
2. A five gallon plastic bucket is one option, especially if we can find a free one.
3. We need to figure out where the container with the plant and MCU Garden system will be kept. It seems like Phase 1 should mostly be indoors because that means we don't need to have a rain-proof system. But having a Phase 1 container that's easily movable would be nice so we can roll or carry the container outside on nice days.
3. Growing condition sensors
1. Light sensor -- very important so we get good photosynthesis (and good respiration?).

   

   One type of light sensor (from Adafruit)

2. Soil moisture sensor -- very important because too dry means 'dead plant' and too wet means 'dead plant.'
3. Temperature sensor -- important for growth, especially during Humboldt winters. Temperature will be less critical for plants like lettuce, but very critical for plants like tomatoes.
4. Relative humidity sensor (RH) -- RH won't be critical for lettuce growth in Phase 1, but it will be critical as the project's future phases try to minimize water usage and as we try to grow RH-sensitive plants like redwood trees.
4. LEDs for indoor gardening
1. RGB LEDs will let us adjust the light if we want
2. Red and Blue LEDs appear to be used for optimum lettuce growth.
3. Research and / or people who know plant growth lighting and LEDs are required.
5. MCU to gather and record sensor data
1. Which MCU we use for the Humboldt MCU Garden project depends partly on who wants to be involved with the project.
1. If we can get a sponsor for the Humboldt MCU Garden project, such as an MCU manufacturer or distributor, I'll use whichever MCU they manufacture or distribute!
2. If no MCU manufacturer or distributor sponsor can be recruited, the MCU will be determined by whoever takes the lead on programming for the project.
1. If Ed takes the lead, we'll probably use a Texas Instruments MCU.
2. If Josiah takes the lead, or if I'm filling that role, it will likely be an Arduino or Arduino-compatible.
3. If someone other than Josiah, Ed or me volunteers to lead the garden-variety programming for this project, that person can choose the MCU type.
6. Type of soil
1. Determining what type of soil to use will require research or a project member who has good experience with growing plants indoors in containers.
2. The type of soil will likely affect other gardening aspects such as what nutrients we need to add and the soil moisture measurement.
7. Fertilizer and trace nutrients to add
1. Fertilizer and trace nutrients is another topic that will require research or a project member experienced in the art.
2. Might want to evaluate whether pH or some other batch or continuous sensor (pH? nutrient analysis?) should be used to track nutrient levels.
8. Data gathering and analysis
1. There are no specific requirements for data gathering and analysis for Phase 1 since it's such a simple system. However, part of the purpose of Phase 1 is to learn how to effectively monitor growing conditions, so it makes sense to establish good gardening data practices (GGDP) for those growing conditions and different types of sensors.
   
2. As part of my goal to get Humboldt people more involved in the Internet of Things (IoT), it would be good to use services like open data bases and IFTTT (If This Then That).
3. One 'gardening data' goal is to use that data to automatically track, alarm and interpret the data generated by the sensors. It would be nice to generate online graphs and have alarms sent out by IFTTT when growing conditions reach or approach setpoints where action needs to be taken.

The above outline give you an idea of what I think Phase 1 of the Humboldt MCU Garden group project should look like. Next steps for me to get this project rolling are (1) talk to and try to recruit a couple people who've expressed an interest in MCU gardening, (2) promote the project to other people in the Humboldt Makers and MCU group and try to recruit some of them, (3) develop a one-page MCU project proposal that I can use to pitch to potential sponsors, and (4) continue to do research for Phase 1 topics like sensors, nutrients and soil types.

If you are interested in this project or know someone who might be, please email me at arcatabob (at) gmail {dott} com or come to an MCU group meeting or Humboldt Makers meeting in the near future.

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