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Not posted for a while. I tend to push on development of mqttcogs during the summer as I use it to monitor and control my watering in my garden. I spent quite a bit of time pushing on development of mqttcogs, I just haven’t had the time to detail exactly what I’ve done. I will do, when I’ve tested it some more and finalised a few odds and ends.

Here’s a brief bullet point list of some new features.


Added two new tabs (third tab contains the settings)

  • Ability to view the last n mqtt received messages
  • Ability to view the last n log messages

Editing – a Thing

Rather than just using short codes to display mqtt data. I added in the concept of a ‘Thing’. You can now create a ‘Thing’ and set associated thing properties – in particular, the associated mqtt topic.

When you edit a thing, you create a post like any other but have the option of inserting ‘canned’ mqttcogs shortcodes into the editor really quickly.

You can also replace the ‘hard’ mqttcogs topic with the thing slug if you wish. This is pretty neat as it allows you to replace a sensor, you only need to update the mqtt topic at the post level rather than each shortcode that uses it.

I’ll admit that this bit is not finished. The reason is that I also want to be able to associate the Thing with a geographic location or shape. So you can include a GeoJSON fragment as well. This can be used if you decide you want to use a leaflet map.

I’ll post some more when I’ve tidied these up and tested them…

Here’s a quick example. http://mqttcogs.sailresults.org/thing/seed-propagator/


This is a test page for me, for my moisture sensors. So won’t make much sense at the moment.


  • Moisture reading fluctuation with temperature
  • Morning high moisture content – due to condensation between plate and insulator?
  • Calibration of sensors


  • 2M resistor here (Air~83 Wet~122 @20C (130 @50C), Soil~119 @ 25.5)
  • Probe covered with epoxy resin. Try to remove issues with moisture condensing between covering and blade

Sensor 93

Sensor 92


This sensor is shoved into the ground in my vegetable bed. It’s actually quite useful. Come spring I’ll know when the soil has warmed up enough to start planting my summer seeds. I also like the way the soil temperature lags behind the air temperature. Obvious, but interesting to watch!


My Umbrella Plant

This page is devoted to my Umbrella Plant. I don’t love my Umbrella Plant as much as my Basil. It has some flaws. It’s not edible and it doesn’t really grow fast. It also collects a lot of dust. It also appears to be able to tolerate large periods of drought as i’m not very good at watering it.

[ mqttcogs_drawgoogle options="{
  series: {1:{labelInLegend: 'Air'},0:{labelInLegend: 'Soil'}},
  title:'(8) Umbrella Plant Temperature',
  hAxis: { title: 'DateTime(UTC)',format:'dd MMM HH:mm' },
  vAxis: { title: 'Temp (F)' }}" 
  charttype="LineChart" ]
          [ mqttcogs_data limit="100" topics="mysensors_out/8/1/1/0/0,mysensors_out/8/2/1/0/0"]

[ mqttcogs_drawgoogle options="
 {series: {1:{labelInLegend: 'Air'},0:{labelInLegend: 'Soil'}},
 title:'(8) Umbrella Plant Moisture',
 hAxis: { title: 'DateTime(UTC)',format:'dd MMM HH:mm' },
 vAxis: { title: 'Moisture' }}"
                [ mqttcogs_data limit="100" topics="mysensors_out/8/0/1/0/37"]