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Measuring leaf surface temperature with the grow sensor
Are you measuring your LST?
As we’ve discussed loads on this site, VPD is super important for optimising your grow room environment.
It’s the key to solving many of the issues that reduce yield and the quality of your final harvest.
In fact, learning how to create the optimum environment for your plants year-round is the best thing you can do to become a better grower.
It’s also one of the main areas people overlook and struggle with!
But how much do you know about leaf surface temperature and the effect it has on your VPD?
When I started paying attention to LST it was a total game changer for me and my growing journey.
If you want to take your cannabis quality to the next level, check out our deep dive into leaf surface temperature now.
(This is a 13-minute read, so grab a coffee and get comfy)
Lets dive into leaf surface temperature
Measuring LST is easy, and every grower should be doing it!
Grow cannabis in a perfect environment, and there’s a great chance you're going to have a super high-quality product.
Most growers kill their quality with love, too much food, too much heat, too much light, too much watering.
Let’s focus on too much light/heat for the moment, which is where LST usually comes into play.
Have you ever had a grow where your buds smelled better, were more sticky and had more crystals lower down the plant?
I’m sure most of us have. What’s that about?
You see it on Instagram loads; a grower will zoom in to show you their killer buds but don’t show you the top colas! They show the buds lower down the plant.
Too much heat is a killer in the grow room and can reduce trichrome production considerably.
Even newer full-spectrum LED grow lights can pack a heat punch at the canopy, which many growers overlook.
A lot of LED manufacturers don’t take LST into consideration when suggesting hanging height.
Measuring ambient temperature at the canopy with a sensor helps for sure!
It can unlock half the picture but it’s not a true representation of what the plant is feeling and experiencing and this is the key to growing the best plants.
Grab an IR heat gun and start measuring the temperature of your leaves and buds.
The Grow Sensor also has a bottom-mounted LST sensor that can measure VPD 24/7, but more on that next week.
There are different leaf surface temperature goals to hit for veg, in flower, and with and without CO2.
Find more info on that here, but in brief:
- Veg 28°C (30°C with CO2)
- From week 6 of flower 26°C dropping by 1°C weekly.
The key takeaway is that if you don’t measure, you won’t know. LST is easy to measure and it’s a direct indictor of plant health.
Data is king.
Measure LST with the Grow Sensor.
For those of you who have started measuring your LST, what are you finding? Is it hotter or colder than you thought?
Using an IR thermometer/heat gun is a super cheap and easy way to get an immediate one-off reading of your LST in your grow.
(You can also get thermal cameras if you want to splash some serious cash.)
But unless you're with your plants all the time and taking readings, you won't get a complete picture of the leaf surface temperature over a 24-hour period.
As mentioned before, measuring LST is essential as it's probably the easiest way to get a health check directly from the plant.
Most of what we measure in a grow room is the surrounding ambient environment, which is super important, but it's 1 step removed from the plant itself.
The Grow Sensor has an LST sensor built into the bottom of the device. This means you can get a full time-series breakdown of your leaf temps throughout the day and night.
Just hang your sensor over a leaf at the canopy level, and you are all set.
This is super powerful, but it gets better.
The Grow App has a setting that allows you to measure your VPD from your leaf temp.
This means you're getting your VPD measurement based on what the plant is experiencing 24/7!
Complete LST clarity and true VPD value directly from the plant.
Less guesswork, more data, the best environment and the healthiest plants!
If you want to know more about this feature, drop me a message!
.avif)
