Saturday, January 28, 2023

Hot Pepper Grow-Op

 About a month before Christmas, I bought myself this hot pepper seed kit from Oh! Canada Seeds in Halifax, NS:


The kit contains seeds from 3 types of peppers: jalapeno, habanero, and ghost. I enjoy eating fresh peppers with various types of food, and had experimented previously with growing some tiny hot red peppers before, which were quite enjoyable in limited quantities, so this was a bit of an experiment to see if I could grow and eat some much hotter varieties. According to the kit, jalapeno peppers are between 2500 and 8000 on the Scoville scale of spiciness. For me this is a comfortable level. I enjoy eating maybe one or two small jalapenos with a few slices of pizza or a plate of nachos. 
Habanero peppers are in a different league though: 100000 to 350000 Scoville heat units. I'm pretty sure I've never eaten anything that hot. And ghost peppers nearly top the chart: 850000 to 1041427 Scoville units (that's a lot of precision!). According to the seed kit, the only thing hotter is the Carolina Reaper pepper (1400000 to 2200000 Scoville units). 

Naturally, the peppers would need to be started indoors, in my small greenhouse. The greenhouse is constructed from metal tubing, and has an opaque plastic cover around it. It is maybe about 2 ft x 2 ft square by about 5 ft high and is kept in the laundry room of our house. To make sure the plants get enough sunlight and heat, in the past I have hooked up a UV grow light and incandescent bulb (for heat) to a light-timer circuit. This has generally worked OK, but the timer circuit sometimes needs to be adjusted if the power goes out for a significant length of time, and it isn't as much fun as having a microcontroller-based setup with digital control and data. 😜

So the idea was to complete a small Arduino-based project over the Christmas break to provide simple on-off control of the heating / lighting and provide some data feedback on the temperature and humidity inside the greenhouse, which could be used for deciding when to provide more water to the growing plants, or possibly at some point in the future for adding an automated watering system. Of course, things were busy over the Christmas break with traveling, illnesses, and afterward, work commitments. So the small few-day project has turned into a month-long project, before it could reach an acceptable point where I could at least blog about it. 

One major goal in completing the project was to figure out some way of using the same HM-10 BLE (Bluetooth low-energy) device that is used on the AMOS Remote for communications with a host PC that could be used for data viewing and graphing. There is a wealth of online information about how to interface to the HM-10 and related BLE devices with a mobile Android or iOS device, and that was what I used for the mobile Boat Captain software that runs on Android phones and tablets. Surprisingly though, there seems to be very few examples of how to communicate over BLE using a PC. I was however, able to find this project: https://github.com/sensboston/BLEConsole which turned out to be a really well written C# console application for doing every possible thing you could ever want to do with BLE devices connected to a PC's Bluetooth radio. I was able to adapt sections of this code to work in a simple GreenhouseViewer app that I created for viewing data from the greenhouse:


Similar code changes could be made for the PC BoatCaptain software to allow the PC to connect wirelessly to the AMOS Remote, which in turn connects wirelessly to AMOS. Currently, the AMOS Remote needs to use the included USB cable when it is being used with a PC. If the AMOS Remote were situated atop a pole for better line-of-sight however, using the USB cable would likely not be practical. 

So far, the only plants that have sprouted are the jalapenos:



Possibly the hotter peppers require more time? Or maybe this is just the universe's way of protecting me from too much spiciness. 

Here are some other pics of the setup: 



Not shown are some blankets that are draped over the outside of the greenhouse. The blankets serve as insulation for keeping in the heat and for preventing the harsh UV light from hurting anybody's eyes. I have noticed that the humidity shoots momentarily way up at night (> 80% and then gradually settles to ~ 70%) when the heat and light get switched off. This probably isn't great for the electronics, as they are openly exposed to the air. I've done similar stuff in the past though, and never experienced any problems, so hopefully it will be OK here too.