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The Heatmap of LetsGrow.com provides new insight

The Heatmap of LetsGrow.com provides new insight
LetsGrow.com has developed the heatmap to provide more insight into the differences in temperature and RH in a greenhouse. Climate fluctuations in the greenhouses are unwanted. It can lead to problems with the growth of the plants in "the corners of the greenhouses", which in turn can lead to differences in production and quality. Climate fluctuations can lead to molds or other diseases that can affect your plant. How can you prevent this?


Horizontal differences in temperature and RH
By this moment, a greenhouse has a limited amount of sensor units that are connected to the climate computer.
These sensor units measure the temperature, RH and the CO2. These units present the data as if the climate in a greenhouse is evenly spaced. However, recent research has shown that there are greater differences between temperature and RH in a greenhouse than has been thought earlier, according to Ton van Dijk, salesmanager LetsGrow.com


heatmap THeatmap RV 1


Insights in temperature
Since a few months, it is possible to show the data from all your sensor units in a heatmap.
With the data out of the sensor units we can make an overview of the temperature and relative air humidity in the greenhouse, even on a 5 minute basis. By showing these measurments as a movie, you can get a perfect insight into the temperature in your greenhouse.


Technical adjustments
we can make a 3D overview of the greenhouse, by hanging the sensor units at different heights in the greenhouse, for example between the plants, at the head of the plant and at the screens.
Ton van Dijk: "With the help of this measurments, we can seriously think about technical adjustments that are needed for the greenhouse, in order to optimise the climate in the greenhouse"


Sensor units
Letsgrow.com can collect, present and analyse the data of every sensor unit. In this way, the heatmap can be expanded by measurements of other systems. With this data, we can make correlations between the different measurements. By making these correlations, we can explain the different situations in your greenhouse and help you to prevent the plants from growth or quality differences, diseases or pests. Our goal is to give you a higher production with a better quality.


Are you interested?

Are you interested in the possibilities for your company? Please contact LetsGrow.com via This email address is being protected from spambots. You need JavaScript enabled to view it. or via our telephone number: +31 10- 460 81.08



Van den Berg Est best Dutch Hortensia grower


Van den Berg Est BV is the best grower of Hortensia in The Netherlands. Marjanne and Tom van den Berg won the Hortensia Award with their Hydrangea macrophylla Caipirinha®. Grower Tom van den Berg: “It all starts with balance.”

Marjanne and Tom van den Berg from Est started growing Hortensia’s for indoor and outdoor uses in 2004. Besides, their company Van den Berg Est BV is a high quality producer of Poinsettia and 1-year-plants. Every friday and saturday the products are being sold at the nursery.

Average vase life of over 35 days!

In week 12 Marjanne en Tom van den Berg admitted the Hydrangea macrophylla Caipirinha® for a test by Knowlede Centre for Product Quality Royal FloraHolland. Caipirinha is a new Hortensia with a distinctive colour. The Hortensia starts green, turns white and then again turns green.

The test was constisted of three phases: Transport (96 hour, 15ºC, packed, in a tray), Shop (72 hour, 20ºC, in a tray) and Consumer (840 hours/35 days). The result: a average vase life of over 35 days!

Three different variables

“At our nursery the plants are the starting point of all our decisions”, says Tom van den Berg. ” Throughout the year we use three different variables: energy, water and ‘assimalates’ of the plant. Therefor our stock is healthier and have more resisant and our customers can enjoy our plants much longer.”

Monitoring these balances is highly automated at Van den Berg Est BV. The company uses the Climate Monitor by LetsGrow.com. Yuri Alsemgeest of LetsGrow.com congratulated Van den Berg Est BV with a delicious cake.


"With LetsGrow I extract more information from my greenhouse"

"Pushing the limits of Next Generation Growing"

Joost Matijsen grows high wire cucumbers. In itself that is not so unique in the Netherlands anymore. He is a leader when it comes to relying on automation in the greenhouse. With the LetsGrow system he pushes the limits of cultivation. "Thanks to the data we can move forward with Next Generation Growing."

Joost Matijsen grows high wire cucumbers for Green Diamonds on 3 hectares in Etten-Leur. To optimize cultivation he has been working with the modules developed by crop advisor and Next Generation Growing (HNT) trainer Peter Geelen for LetsGrow.com for years. The climate computer sends information to the system. "LetsGrow adds up and clarifies the data. This way connections can be made and more information can be extracted from the greenhouse."


Information sharing
Two years ago Matijsen installed vertical fans and a plastic screen to move forward with HNT. He follows HNT courses that use LetsGrow analyses. Matijsen: "Then we can discuss them at the next meeting. It makes the conversation more reliable and faster."

Isn’t that precisely what makes growers shudder; sharing information with potential competitors? That’s not how he sees it. "If you are willing to share data you can have a good and honest discussion. And when you are an HNT student you’ve already opened up to something new. You’ll be pushing limits to move forward. And then it's nice when others are observing. Together you can go further, that’s the big advantage.”

Green Diamonds
Besides the HNT course group Matijsen also collaborates within the Green Diamonds cooperative. The growers want to distinguish themselves on quality and assume that the life span of a cucumber begins with the plant. Matijsen: "The longer it hangs on the plant, the shorter the life span. The cucumber is the opposite of a cut-price chicken. The faster a cucumber grows, the tastier and fresher it comes off the plant. You can hang a plant full of cucumbers, but that won’t improve the quality."
This is why growers make plant load predictions in combination with light incidence. "With the right scale you can immediately see how you should steer. Whether extra pruning is needed, or if next year you should get an extra stalk in." LetsGrow data are shared in this regard as well.

If it’s up to Matijsen, automation can go much further in the future: "What we use now is a robust system. Thanks to, for example, Peter Geelen’s modules LetsGrow is already calculating the numbers from the climate computer. What if you start steering on the basis of those numbers? HNT has shown that you have to attune the daily temperature to the amount of light. If you have a lot of light, you use a higher temperature."
"A next step could be to feed information back from LetsGrow to the climate computer." Not being involved with the greenhouse at all – that's something he doesn’t see happening. "But we do see with HNT that most problems happen overnight. You need your sleep so you won’t notice it until morning. And then you can’t do anything about it anymore. To overcome this, you will ultimately have to rely on automation."

Prevent diseases and damage with Thermoview 48

If the temperature of a flower or fruit drops below the dew point several diseases may arise, such as botrytis and head rot. However, if the temperature is too high, there is a risk of damage. LetsGrow.com now has the solution for this: a thermal camera that can be combined with data from your climate computer. The Thermoview 48 measures the temperature in your crop and gives a signal when, for example, the crop reaches the dew point.

themoview letsgrow

LetsGrow.com collects and analyzes all data professional growers need to improve their production and business operation and to eliminate risks. Manager Peter Hendriks from LetsGrow.com: "We’re often asked if we have a solution to prevent diseases and damage. Wouldn’t it be nice if the growers gets a signal when flowers or fruits are too hot or too cold? This way you can prevent damage and diseases. Much wiser than only betting on the cure after the fact!"


LetsGrow.com is launching the Thermoview 48 together with a supplier of thermal imaging cameras. Hendriks: "We’re very proud of this. With this thermal camera, connected to the LetsGrow.com platform, it is possible to measure fruit, flower and plant temperatures in real time with only one device!"

themoview camera
The LetsGrow.com platform also provides access to other data sources, so it’s possible to obtain both the temperature and the RH from the climate computer or other (wireless) sensors in real-time. This way the dew point can be calculated. Hendriks emphasizes that the camera is an extension and not a replacement of existing climate computer sensors.

“I steer to this now”

Some growers recently tested the Thermoview 48 and LetsGrow.com and could so experience the effect of crop radiation on head temperatures. One cucumber grower: "You can clearly see the effect of screening on the head temperature. I can see it in the charts, but also in the photos that are taken every hour and are playable as a movie. That gives me a lot of insight into the behavior of the heads under different conditions. I steer to this now. I consult the result with my crop advisor. And we have many meaningful discussions about the newly generated insights."

thermoview graph
Vertical temperature differences

In conjunction with the LetsGrow.com platform the Thermoview 48 provides more relevant information, says Hendriks. "For example, it is possible to detect vertical temperature differences at one glance. You really know what's going on with your crop, in real-time and with historical data."

Migration LetsGrow servers

On 12 November at 18:00 CET we are migrating our servers to another data center. We expect to be up again at 22:00 CET.

LetsGrow.com continues to innovate! We constantly strive to expand and improve our products and services.

As you know your data is stored in our secure database. Our servers and database are not hosted “in the cloud” but in a physical location in a data center in Rotterdam. Because the servers are now due for replacement, we also selected a new data center. In the new data center, we have our own, new, physical servers.

With the migration to the new data center and servers, we also implemented a quality improvement, resulting in an even higher availability and reliability. We ensure that everything is dual (redundant) performed: the servers, the software and the database. If any of these components malfunction, then the other one will take over. You won't even notice this.

What does this mean for you?
· The site will not be available for a couple of hours.
· The preparations are made so that data loss will not occur.

We are fully busy with preparations for the migration and will keep you informed the coming days.

Keep an eye on our website!


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PO Box 108
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The Netherlands
T: +31 (0)10 460 81 08
F: +31 (0)10 460 80 00