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ProJoules makes it more convenient for growers with intermediate step to cultivation plan

More and more growers are discovering and using the model-based crop planning platform ProJoules, which has now been on the market for more than two years. To make it ever easier for all new and existing users to use, new updates are constantly being worked on. A new feature recently added is that growers can now create a crop plan without having to enter data that can be calculated automatically. This is possible because the programme itself makes more calculations including the radiation temperature ratio (RTR).

ProJoules is a model-based crop planning platform for fruiting vegetables. The basis, as the name suggests, is light. Or rather, Joules, the total sum of light energy in the greenhouse at plant level. To use ProJoules properly, crop-specific data are needed.  Some data are known in advance. The makers of ProJoules help the grower by making more and more data available in advance, think for instance of the variety profiles.

Certainly new users of ProJoules sometimes still appeared to be put off by ‘a blank screen’ as a basis for entering data for calculations. To make it easier for users to get started, variety profiles, among other things, have been integrated. These contain, for example, the optimal 24-hour temperatures and variety-dependent numbers of joules per gram for all fruiting vegetable crops currently used in ProJoules. Should new varieties come onto the market, the variety profiles are regularly updated for this purpose. 

Intermediate step towards cultivation plan
Also new is an intermediate step(Preplan) when creating a crop plan. Previously, growers entered the final plan immediately after creating a crop. Growers can now make an intermediate calculation after selecting a variety and filling in the much-needed key figures. For example, growers themselves fill in the desired stem density for some specific week numbers, bunch development data and then get to see the plan on the right in the new screen. For this, ProJoules has filled in missing numbers itself by making calculations.

The data, both self-entered and pre-entered, can be changed by growers. Indeed, it is emphatically not the makers’ intention to chew out everything for users. For the makers, it is important that growers start learning about the optimal planting balance, with the safety of virtually seeing what happens when parameters change, without immediately losing the harvest.

Stem density
“Importantly, growers can play with stem density in the new screen, for example,” thinks Wim van Wingerden, the initiator of ProJoules. “I know users who have gone up by ten per cent in stem density thanks to the insights from ProJoules.” The system helps the grower towards the most optimal stem density, cluster size etc in relation to available light. 

The other way around is also possible. The energy crisis led growers to reduce lighting at times. This has an undeniable effect on crop planning. “You can now also make a copy of your original plan in ProJoules, retaining all the data, adjusting only the artificial light dates, for example. That way, you can then search for the optimal planting balance under new conditions.”

Besides the new Preplan screen and the integration of variety profiles, calculating the radiation-temperature ratio (RTR) is new. Remarkably, ProJoules thereby calculates the RTR based on inside light. “We do that differently from others,” Wim acknowledges. “In the market, RTR is often about outdoor light, but we actually believe that you have to look at light at plant level. We therefore include factors such as coating for outdoor light as well as artificial light in RTR’s calculations.” 

Before growers calculate RTR, Wim advises growers to first achieve an optimal planting balance. And so for that, the necessary updates to the model-based crop planning platform have been implemented. “Crop planning is becoming easier and, above all, more accurate,” he says.

This article has been written by Hortidaily and has been republished on