January 13, 2022

RED x Thomas Plants

Amongst the French market leaders for vegetable production

Founded in the 1990s by the Thomas brothers, the Thomas Plants Group has two production sites: Ploubazlanec in the Côtes d’Armor and Tarascon in the Bouches-du-Rhône. The Thomas Plants Group operates more than 12 hectares of heated and lit glass greenhouses in which 250 employees work on a daily basis and up to 500 during the peak winter production periods.

Today, the company is managed by Nicolas Paul and produces 250 million young plants per year. Production is spread over three main periods:

– Winter: Thomas Plants produces mainly warm plants for greenhouse vegetable growers

– Spring : The production is diversified with all the typical vegetables that can be found in a gardens as well as onions, cabbage, beets and sweet potatoes

– Summer: This is the high season for young cabbage plants

"Thanks to the experience of our team, we know at what date to sow, graft and transplant in order to promise a delivery at a given date."

Nicolas PAUL
President - Thomas Plants Group

Knowing how to meet increasingly demanding customer expectations

The production of young tomato plants is a crucial period that represents 30 to 40% of Thomas Plants’ turnover. The level of technology required to grow tomatoes is constantly increasing and requires young plants of increasingly high quality. Jérôme Crenn, the group’s R&D manager, ensures that production meets these changing customer needs.

"Producers expect strong agronomic qualities and increasingly earlier in the year."

Jérôme CRENN
R&D Manager - Thomas Plants Group

A lighting strategy in full transformation

Historically, like most growers, the Thomas Plants Group uses sodium or HPS lamps for the cultivation of its young plants. However, Nicolas Paul believes that the competition from the controllable LED solution is pushing HPS technology to the end of its life cycle:

"HPS technology has a fairly mature life cycle and will need to be renewed in the coming years."

Nicolas PAUL
President - Thomas Plants Group

Jérôme Crenn also considers that there is a lot of room for improvement when switching from HPS to controllable LED.

Aware of these issues for young plant producers, RED Horticulture met with Thomas Plants in 2018 to explain its concept and its benefits. Louis Golaz, Managing Director of RED Horticulture, explained, “A young plant has the unique feature of having very different stages in its production: sowing, post-grafting, transplanting… At each stage the plant has different light requirements, hence the interest of controllable lighting with a portfolio of different light recipes.”

The Thomas Plants Group benefited from RED’s customized and tailored solution for the cultivation of young plants.

"In 2018 the knowledge we had about horticultural LED was generic. There was a feeling that the existing systems were not adapted to the needs of plant growers. With RED I found there was a really innovative concept in this notion of wavelength adapted to the plant."

Jérôme CRENN
R&D Manager - Thomas Plants Group

After identifying the lighting needs, the Thomas Plants group was equipped with TAURUS 600 controlled by the SOLSTICE application. 10 light recipes were identified and implemented thanks to a joint literature review carried out by RED and Thomas Plants. Jérôme Crenn explained: “For example, we have a recipe that aims to improve seed germination and another that is perfect for post-grafting recovery.”

The greenhouse is equipped with sensors that interact with SOLSTICE. They provide all the information needed for light management.

“The crop managers define the light recipe to be adopted according to the stage of the plants or varieties they have,” says Jérôme.

"The literature review was essential in order to obtain the expected results right from the first season. At this stage of development, young plants are very sensitive to light and their behavior changes rapidly from one spectral recipe to another."

Raphaël QUENUM
Agronomist - RED Horticulture

A close working relationship for a successful outcome

The difference between the HPS and the RED solution is clear with very positive and encouraging results for the future :

"RED lighting brings us energy savings, agronomic quality, a more precise production time and a cultivation schedule more suited to our production."

Nicolas PAUL
President - Thomas Plants Group

Jérôme Crenn emphasizes that their production sites now have a new technical instrument to perfect the cultivation of young plants. Temperature management and humidity have been known for many years, and now RED Horticulture offers a coherent solution for understanding the photobiology of young plants. 

There are many advances in the definition of the lighting strategy. Thomas Plants’ crop managers report their observations to the RED Horticulture teams, enabling them to fine-tune the lighting recipes.

“As soon as we have a new requirement, we call RED’s R&D department, with whom we start tests,” explains Jérôme Crenn.

Much more than a simple customer relationship

Based on regular discussions, the RED-Thomas Plants relationship has been built with a common goal of establishing the foundation of photobiology for young plants.

"We have created a genuine partnership with RED. We are constantly co-building the development of solutions in the field for a multitude of different species at the seedling stage."

Nicolas PAUL
President - Thomas Plants Group

After an initial trial of 1,000m2 on the Ploubazlanec site in Brittany, the Thomas Plants group has deployed the RED solution on 4,000m2 in Provence.

“Thanks to the advantages of this solution, we will continue to develop LED lighting surfaces in the coming years,” concludes Nicolas Paul.



Discover the solution used by the Thomas Plants group. Sensors, luminaires, control: nothing is left to chance to optimize performance.