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Growums seed gardening kit for kids review

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I am a sucker for kids seed growing kits especially when I pass by them on clearance.  The one I found was the Growums Herb Seed Kit at Lowes on clearance for $2.49, though typically they run for $5 so not a bad price at retail.

The kit includes 8 peat pots, bottom watering container to hold them, and ~20 seeds of basil, cilantro, oregano, parsley (each with matching labels for each peat pot with colorful characters on them. 

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It also came with a secret code that gives you access to an online site where the kids can watch for directions on how to start their plants and some additional advice on topics such as watering and pest control in short animated videos which had a bit of a Veggie Tales feel to them (minus the religious stories)  The site also features a few garden related games for the kids to play.

Overall I like the design of the planter as it is very easy to setup basically place it on a sturdy container (cake/pie pan) and add a cup or so of water and watch the peat pots grow and plant 3 seeds in each pot and then water as needed and bring outdoors.  I think the online portion is a nice touch to get your kids/grandkids dig a little more into the caring part of the plants versus planting some seeds and heading on their way.  Given this uses standard sized peat pods you can easily use the planter again and again with the remaining seeds or any other variety you choose.

Along with the “herb garden” we got they also offer a “taco garden”, “salad garden”, “pizza garden”, “ratatouille garden”, and “stir-fry garden” which offers different selections of seed varieties associated with the theme.

Protecting your transplants with window screens

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Typically I do my best to give my plants some chance to harden off by reducing the low-end temperature of the grow box and bumping up the extended time the internal fan runs as well as letting them have a few hours out in real sun when schedule and weather permits.

Fortunately/Unfortunately eventually these plants have to venture out on their own.  To provide some protection to these plants for the first few days (or extended periods of very hot weather) it is best to provide screen to allow the plants to acclimate to actual sunlight.  Of course you can buy some netting screen but having a pretty small yard and even smaller garage this is something I do not want to pay for nor have to fold back up and search for again until it is needed again. 

My solution is to “borrow” the window screens from a couple windows I pretty much never open (behind my desk I am typing at now) this provides a good screen with a sturdy frame which as you can see I have simple rested against a fence…though if you did not have a similar structure you easily could use a couple bamboo poles or stakes to hold the screen up.

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Great part after a few days or week you simply snap them back into your window where you will easily be able to find them next year…

How to make a grow box controller

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While my existing system was working I decided to make an upgrade to the electronics on my old grow box controller specifically to have a much more industrial strength version that will run without problems for decades to come.  This version also is much safer…still probably not quite to a building code but much less worries to burning my garage down in the middle of the night.  Finally it is modular if there are problems in the future I can easily switch out electronics or sensors.

Well now I have attempted to justify my reasons this is what I used to put the whole thing together:

Parts List

If we had lawyers, they probably would want us to say this:
WARNING: I am not an electrician and do not pretend to be one.  I do not know the specific building electrical codes of your area, so please be sure your wiring is completed under the proper safety code for your area. As always, using high voltage electricity can result in self-electrocution or burn down your house if not done safely so if you are not comfortable doing this wiring please contact a qualified professional.

Putting it all together

On the electronics side overall the circuits are actually pretty simple and if using a breadboard definitely something that could be tackled by a beginner.  Though on the other side since this project is dealing with AC current I definitely would recommend caution (no hands unless power is unplugged) or have someone a little more comfortable with 120/220V help you out.

The Brains


I will be the first to admit that using an Arduino for this application is complete overkill for this application but it gives plenty of room for additions in the future.  For all intents and purpose you could have your grow box completely controlled from the Arduino own processing power though on my case the software and UI is more interesting part to me.  For this reason the Arduino code is actually very “dumb” basically just taking commands via the build in serial through USB and setting digital outputs to HIGH/LOW or reading analog inputs.

Here is the code for your grow box controller:

   1: /*

 

   2:  * GrowBox Arduino Interface

 

   3:  *

 

   4:  * Descriptions: Simple interface to digital and analog controls by passing serial inputs

 

   5:  *               For example: 

 

   6:  *                  "A1" to read analog value on pin 1

 

   7:  *                  "D1H" to set digital pin 1 to HIGH

 

   8:  */

 

   9: #include <OneWire.h>

 

  10:

 

  11: //1-wire

 

  12: OneWire  ds(8);  // on pin 8

 

  13: #define BADTEMP -1000

 

  14:

 

  15: //define unique sensor serial code

 

  16: byte temperature[8];

 

  17:

 

  19: #define PIN_VALUE 1          // numeric pin value (0 through 9) for digital output or analog input

 

  18: #define ACTION_TYPE 0        // 'D' for digtal write, 'A' for analog read

 

  20: #define DIGITAL_SET_VALUE 2  // Value to write (only used for digital, ignored for analog)

 

  21:

 

  22: int NUM_OF_ANALOG_READS = 2;

 

  23: char commandString[20];

 

  24:

 

  25: void setup()

 

  26: {

 

  27:   Serial.begin(9600);

 

  28:

 

  29:   setOneWireHex();

 

  30:

 

  31:   // Power control

 

  32:   for(int i=0; i<=7; i++)

 

  33:   {

 

  34:     pinMode(i, OUTPUT);        // sets the digital pins as output

 

  35:     digitalWrite(i, LOW);      // turn everything off

 

  36:   }

 

  37: }

 

  38:

 

  39: void loop()

 

  40: {

 

  41:   readStringFromSerial();

 

  42:

 

  43:   if (commandString[ACTION_TYPE] != 0)   {

 

  44:     int pinValue = commandString[PIN_VALUE] - '0';  // Convert char to int

 

  45:

 

  46:     if(commandString[ACTION_TYPE] == 'A')

 

  47:       Serial.println(analogRead(pinValue));

 

  48:     else if(commandString[ACTION_TYPE] == 'D') {

 

  49:       if(commandString[DIGITAL_SET_VALUE] == 'H')

 

  50:         digitalWrite(pinValue, HIGH);

 

  51:       else if(commandString[DIGITAL_SET_VALUE] == 'L')

 

  52:         digitalWrite(pinValue, LOW);

 

  53:

 

  54:       Serial.println("OK");

 

  55:     }

 

  56:     else if(commandString[ACTION_TYPE] == 'T') {

 

  57:       float temp = get_temp(temperature);

 

  58:

 

  59:       Serial.print(temp);

 

  60:       Serial.println("C");

 

  61:     }

 

  62:     else if(commandString[ACTION_TYPE] == '1') {

 

  63:       printOneWireHex();

 

  64:     }

 

  65:     else if(commandString[ACTION_TYPE] == 'V')   {

 

  66:       Serial.println("VERSION_1_0_0_0");

 

  67:     }

 

  68:     else if(commandString[ACTION_TYPE] == 'P') {

 

  69:       Serial.println("PONG");

 

  70:     }

 

  71:

 

  72:     // Clean Array

 

  73:     for (int i=0; i <= 20; i++)

 

  74:       commandString[i]=0;

 

  75:   }

 

  76:

 

  77:   delay(100);  // wait a little time

 

  78: }

 

  79:

 

  80:

 

  81: void readStringFromSerial() {

 

  82:   int i = 0;

 

  83:   if(Serial.available()) {

 

  84:     while (Serial.available()) {

 

  85:       commandString[i] = Serial.read();

 

  86:       i++;

 

  87:     }

 

  88:   }

 

  89: }

 

  90:

 

  91: void setOneWireHex() {

 

  92:     ds.reset_search();

 

  93:     ds.search(temperature);

 

  94: }

 

  95:

 

  96: void printOneWireHex() {

 

  97:   ds.reset_search();

 

  98:   if ( !ds.search(temperature)) {

 

  99:     Serial.print("NONE\n");

 

 100:   }

 

 101:   else {

 

 102:     ds.reset_search();

 

 103:

 

 104:     int sensor = 0;

 

 105:     while(ds.search(temperature))

 

 106:     {

 

 107:       Serial.print("S");

 

 108:       Serial.print(sensor);

 

 109:       Serial.print("=");

 

 110:       for(int i = 0; i < 8; i++) {

 

 111:         Serial.print(temperature[i], HEX);

 

 112:         Serial.print(".");

 

 113:       }

 

 114:       Serial.println();

 

 115:     }

 

 116:   }

 

 117:

 

 118:   ds.reset_search();

 

 119: }

 

 120:

 

 121: float get_temp(byte* addr)

 

 122: {

 

 123:   byte present = 0;

 

 124:   byte i;

 

 125:   byte data[12];

 

 126:

 

 127:   ds.reset();

 

 128:   ds.select(addr);

 

 129:   ds.write(0x44,1);         // start conversion, with parasite power on at the end

 

 130:

 

 131:   delay(1000);     // maybe 750ms is enough, maybe not

 

 132:   // we might do a ds.depower() here, but the reset will take care of it.

 

 133:

 

 134:   present = ds.reset();

 

 135:   ds.select(addr);

 

 136:   ds.write(0xBE);         // Read Scratchpad

 

 137:

 

 138:   for ( i = 0; i < 9; i++) { // we need 9 bytes

 

 139:     data[i] = ds.read();

 

 140:   }

 

 141:

 

 142:   int temp;

 

 143:   float ftemp;

 

 144:   temp = data[0];      // load all 8 bits of the LSB

 

 145:

 

 146:   if (data[1] > 0x80){  // sign bit set, temp is negative

 

 147:     temp = !temp + 1; //two's complement adjustment

 

 148:     temp = temp * -1; //flip value negative.

 

 149:   }

 

 150:

 

 151:   //get hi-rez data

 

 152:   int cpc;

 

 153:   int cr = data[6];

 

 154:   cpc = data[7];

 

 155:

 

 156:   if (cpc == 0)

 

 157:     return BADTEMP;

 

 158:

 

 159:   temp = temp >> 1;  // Truncate by dropping bit zero for hi-rez forumua

 

 160:   ftemp = temp - (float)0.25 + (cpc - cr)/(float)cpc;

 

 161:   //end hi-rez data

 

 162: //  ftemp = ((ftemp * 9) / 5.0) + 32; //C -> F

 

 163:

 

 164:   return ftemp;

 

 165: }

Copy and paste the above code into your Arduino software.   For the code above I used the OneHire.h library which is free to use and can be downloaded from here. To be able to use this library simply copy the contents to C:\arduino\hardware\libraries\OneWire. Now you should be able to Compile (CTRL+R) and upload the code to the board (CTRL+U)

Now with the software uploaded you can send some simple serial commands via its built in USB to serial adapter to interact with it.  The interface is are broken up into 1 to 4 character commands, which I will detail below

Command Description
T Returns temperature from One Wire component
D4H Sets digital pin 4 to HIGH (ON) (replace 4 for alternate pin)
D4L Sets digital pin 4 to LOW (OFF) (replace 4 for alternate pin)
A1 Reads analog value from pin 1 (replace 1 for alternate pin)
PING Returns PONG which is used to confirmed controller is online
V Returns version which is some forethought into the PC application being able to support different versions of controller software

Using the build in serial monitor tool in Arduino.exe, my application, or you should be able to control your Arduino with this very simple command based interface

Now you can hook up some LEDs and watch them blink which is fun for a little while but if you want to add some grow box components read on….

Temperature Sensor

As you can see I have fully embraced the circuit schema on the back of a napkin idea.  These are the actual diagrams I crumpled up and stuffed in my pocket with several trips to the garage for some final soldering of various joints until everything was solid.

Below is the simple circuit required to get your 1Wire temperature sensor working.  I would recommend checking your documentation (if not labels on the chip) for the orientation to have 1 and 3 correct, if you have it wrong you should get some complete unrealistic number.  Hook ground up to pin1 on the DS18S20 and pin 2 hooked up to the digital input pin 8 on the Arduino with 5V with a 4.7K resister in between to step down the voltage.

If everything is hooked up correctly you should get the current room temperature in Celsius by sending command “T” to your Arduino.  If you prefer Fahrenheit uncomment line 162 and recompile and upload your changes, though if using my software I support both degree types and do the conversion in the the software.  To make sure everything working (or just to play with your new toy) put your fingers on the chip for a couple seconds and take another measurement unless you keep your house very warm the temperature should go up a couple of degrees

1WireSensorDiagram

Turning things on and off (Relays)

If you were smart enough to check the current requirements of your Solid State Relays (SSR) before you bought them you may be able to skip this whole circuit and simply hook the digital outputs to the 5V positive side and ground to the negative side of the SSR.

Unfortunately if you are like me and bought some SSRs that require more current draw than the Arduino (or any other IC chip) of 40mA then you will need to create the simple circuit below.

image

Basic idea is pretty simple, you are using the output from the digital pins to switch of the transistor which then allows the ground to complete the circuit with the thus turning on the relay.  As you can see there is a 1K resistor between the base (middle pin) of the transistor.  If you are not using a SSR relay (though recommend you do) you should add a 1N4004 diode between the positive/negative which protects the transistor from being damaged in case of a high voltage spike which can occur for a fraction of a second when the transistor switched off, this is also known as a back-EMF diode or fly back diode.

Now here you have a couple options.  If you are confident of our wiring skills you can do like I did and take a couple of sockets and hook up the neutral and ground in parallel.  Two save space and since I really didn’t need two separate plug-ins (nor its own plug) for each relay I removed the little metal bar between the two sockets so they could be switched on independently.  Now simply hook up hot to the left side of all your relays in parallel and then connect a wire from the right side of the relay to its own plug on the two sockets.

Now a less wiring intensive method is to simply take a 6 foot (small if you can find them) and cut the hot wire (usually the one with non-smooth wire) and attach each end of the wire to both sides of the relay.

Moisture Sensor

When it comes to a moisture sensor there are a few options.  First is the classic two galvanized nails, second is the cheap gypsum soil moisture sensor which I have written up in the provided link.

If you are using the other options you will need the simple circuit below.  Technically it is a voltage divider, but that doesn’t really matter.  Just hook up one end of your sensor to 5V and other sensor to ground with 10K resistor and also connected to analog pin 0.

SoilSensorDiagram

My custom PCB solution

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I actually started the work to create my own PCB at least a few years back.  Played with if it off and on and finally pulled the trigger to get some boards printed up which I must say was very rewarding and pretty fun experience for just $20-30 of out of pocket cost.  This provides all the circuits I mention above with a bonus circuit to let me know when my water reservoir is running low.  I also installed a Ethernet socket not

I designed this to be an Ardunio which plugs directly on top of the Arduino.  In theory I could stack more functionality on top of if but haven’t though of anything cool to do here yet.

Don’t want to spend 10-20 hours creating your own PCB and then wait 2-3 weeks for it to arrive from Hong Kong?  Well you can do the same thing with a bread board which I show below.

Virtual breadboard layout

VirtualBreadboard

If you are new to soldering or have no interest in learning I would definitely recommend this option.  Simply place the components in the holes and make connections with 18 gauge solid copper wire.  You should be able to pick a small breadboard for less than $7.

Various applications

Of course for my application, I am using this to integrate with my custom software solution to control my grow box.  Specifically soil sensor, temperature measurement, heater, lights, exhaust fan, and water pump.  So using the circuit mentioned above I ran the hot wire through each SSR with the remaining wires connected to the plug and eventually gets plugged into the wall.  Then simply hooked up the wire from the Ethernet cables to the low voltage side to turn the switches on/off.  So I would say this is a bit of an improvement over my last attempt…

Before

IMG_3777

After

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Last I hooked the arduino up to my PC and used my custom software to control the temperature, water, and provide cool graphs as you can see below.

GrowBoxView

Sometimes life can get busy and you have limited time to keep an eye on your plants, for these times I also integrated with a custom Windows Phone 8 application which allows me to check the current state of the grow box using life tiles, water remotely (turn on/off lights/heater/fan as well), or even check out a current feed inside the grow box.

007 008

009011  010

Looks at the actual actual grow box…

003

008

Opening day at the farmers market 2013

Today was the first day for farmer’s markets to open in my area. Still a bit early for many vegetables but plenty of cold season crops to choose from (kale, asparagus, green onions, etc)

I left with some onions and apples…kids left with some honey, lavender soap, and kettle corn.

If you haven’t made to your farmer’s market it is a great time to find on in your area and give it a visit. Not only are you supporting your community farmers but also getting so great fresh produce.

Molecular composition of DIRT

Dirt molecule

While walking down the hallways at work I noticed a coworker with a caffeine molecular T-Shirt and made me think of the question, “What does a simple spec of dirt look look?”   I know my brain works in weird ways…but anyway what I found was pretty amazing.  Above is what an average molecule’s chemical composition looks like.

For any of you chemistry nerds more specifically this is C349H401N26O173S which is visually represented above. 

Humic Acid

The majority of this molecule is Humic acid which comprises of the majority of organic soil matter (or dirt) which is a very weak acid group partially visualized below as groupings of Carboxylic/Phenolic/Alcoholic/Quinonic/Ketone/Methoxl. 

Humic Acid molecule

Saccharides (sugars)

Next we have the saccharides or as we more commonly refer to as sugar…

 Saccharide sugar molecule

Proteinaceous material

I don’t even know where to start on this amazing hexapeptide…so I will jump to the pretty picture.

proteinaceous molecule

Water

Of course you also have to have some good ole’ H20

Water molecule

Aromatic carbon

Which is a hydrocarbon with alternating double and single bonds between carbon atoms forming rings. 

Aromatic carbon molecule

Now of course not every piece of dirt appears exactly like what is shown above, but this would be the more common of the bunch.  Depending on how you compost and/or sourced your soil you will also have all kinds of neat trace minerals in your soil that will help your plants grow but also provide digestible nutrients to the foods you grow. 

So next time you pick up a handful of soil you can have a even greater appreciation for the cool chemistry that made it all possible.

Source: The Virtual Museum of Minerals and Molecules

Keeping Your Garden Insect Free

IMG_2716

Nothing is tastier during the summer than home-grown vegetables. Unfortunately, insects feel the same way and often destroy vegetable gardens in short amounts of time. To prevent these pests from reaping the benefits of diligent gardening, consider the following tips.

Plant transfers early. While it may be somewhat risky in cooler climates to plant early, this practice can prevent initial pest problems. Insects are not as common during the earlier months, so this is the perfect time to get a head start on a healthy garden.

Keep the garden cultivated and weeded. Healthy soil is a great contributor to pest prevention. Organic mulches often attract insects, so try to avoid these. Weeds should be removed regularly. It is also helpful to add fertilizer frequently and ensure the soil stays moist.

Keep crops covered. Plastic mesh is useful for keeping common insects away, and it is an affordable prevention method.

Plant insect-resistant produce. Some types of vegetables and herbs are naturally unattractive to pests. It is also helpful to rotate crop planting locations by avoiding planting the same families in the same areas for three years. This will lower the risks of damages from overwintering pests living in the soil.

Use pesticides or pest-specific control methods.
Both organic and commercial pesticides can be harmful if they are not washed off before consuming produce. However, they may be necessary for keeping certain insect populations under control. It is best to avoid using pesticides that kill both harmful and beneficial pests. Whenever possible, use a pesticide that is only targeted at a specific problematic insect. The following tips are also helpful for preventing specific pests:

  • Grow chives, mint or basil to keep aphids away.
  • Put crushed eggshells around the bases of plants to prevent snails and caterpillars.
  • Use a repellent with eucalyptol to discourage mosquitoes.
  • Grow thyme, dill or cilantro to keep leafhoppers control.
  • Grow garlic, catnip or yarrow to prevent potato beetles.

Pest problems are not always limited to insects. In addition to these measures, install some chicken wire or mesh fencing around the garden to keep rabbits and other rodents out. Each of these prevention methods are affordable and easy, so they will work for any budget and skill level. And of course, if all else fails, there is always the option to call a pest control professional. Most companies have proven methods and systems to both exterminate pests and ensure that they don’t return.

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