Always the optimum amount of PAR light in the greenhouse and an even dispersion of the sparkle over the harvest ; that is the PARperfect silver screen solvent from Svensson in a nutshell . However , to capitalize on these advantages as a grower , you must know exactly how much dismount your crop can pick up . Because calathea grower Teun Valstar had insufficient perceptivity into this , Svensson bear out photosynthesis measurements at his caller last year . The collected entropy offer the enterpriser chance to optimize the light level in his greenhouse and the harvest growth .
Paul Arkesteijn at Teun Valstar
The Netherlands has only a handful of calathea growers ; Teun Valstar is one of them . For the enterpriser from Honselersdijk , this refinement still entertain few secrets ; he has been sharpen on producing these green plants for 35 twelvemonth . His ship’s company Shadowplant now encompass almost six hectares . “ We recently buy a 1.9 - hectare neighboring company , ” says Valstar . “ This location will finally be run by my Logos Roy , who wants to take over the company in the future . Even during these electric glow times , our sale continue well , partly due to the increase in on-line sale . ”
Optimal use of light capacityScreening is vital in the cultivation of dark-green plants . Too much sunshine can lead to harvest price - in the soma of brown edge and stage - or growth inhibition . " Most growers of dark-green plants screen away between twenty and eighty percent of light , " tell Paul Arkesteijn , climate adviser at Svensson . " The disadvantage of the veritable mood screens is that you are always stuck to the chosen covering academic degree ; you are not or hardly flexible . While at certain time or in sure periods , you could admit in more lighting without damage the crop . However , due to the fix shading degree , you could not make optimal use of the plant ’s light mental ability . "
In reception to this , Svensson introduced the innovative PARperfect screen answer three years ago . This silver screen solution cause it possible to accomplish the want PAR light level in the glasshouse because the screen horizontal surface can vary from twenty to one hundred percent . " you’re able to compare the principle to that of a light dimmer , " say Arkesteijn .
The concept consists of a combination of two climate screens . The top screen door is a screen with a gamy shade degree or a brownout covert ; the bottom screen door is the unique Harmony PARperfect climate cover . This silver screen has a gamey light transmission and a in high spirits Hortiscatter ; the light is evenly distributed over the plant . There are no shadow bands , which is the typesetter’s case with traditional mood filmdom . The bottom blind shut down first in the morning ; the top screen opens and closes found on the solar actinotherapy and the amount of lightness the crop can receive . This is done using a PAR wakeful sensor in the greenhouse linked to the climate computer . With PARperfect , you are therefore always assured of the maximal amount of light in the greenhouse . Without having to care about craw damage .
work it safeTeun Valstar first empower in PARperfect two years ago , after having screened with two regular screens for years . " The fact that you could achieve a more even light statistical distribution in the nursery and there are no dark strips , in special , convinced me , " say Valstar . " This screen solvent now hangs on 23,000 m2 ; the rest will follow in the coming years . In this concept , we meld a screen that limits weak befoulment with the PARperfect climate screen .
Although Valstar has already benefited in late years from a more even clean statistical distribution and thus a more consistent craw growth , he had not yet taken any fundamental steps in optimizing the amount of PAR light in the greenhouse . " Of course , I knew roughly what the flora could take , but not exactly . And to avoid scathe , I played it dependable as much as possible . This meant that sometimes I kept the top sieve closed perhaps more than I needed to . " consort to Paul Arkesteijn , it is not known for many types of potted flora exactly how much PAR light they can have . " This is mainly because the crops are relatively small , so only limited research is being carry out . But to get the most out of the PARperfect screen door answer , it is significant to have a good brainstorm into your crop ’s light capacity " , Paul Arkesteijn at Teun Valstar .
Photosynthesis measurementsTo helper Valstar move forward in this respect and to gain insight into the amount of light that a calathea can have , Svensson contain out photosynthesis measure at the company last year .
" In a section with PARperfect , we installed two leafage photosynthesis detector in May last year , " says the Svensson advisor . " Such a sensing element provides insight into how much photosynthesis takes property , how the works feels , and whether stress arises . The latter is the case when the crop receives too much light . " Arkesteijn analyze the data from the photosynthesis sensors every two weeks between May and September and combine this with uncommitted data about the amount of PAR lighting , the positions of the climate screen , and the greenhouse clime . " Based on this , we mapped out how much visible radiation a calathea can have , both instantly and cumulatively over the 24-hour interval . This was more than we expected . We also see that Teun was quite on the safe side when it come in to screening ; at many time , the industrial plant could have more light than it receive . " The clime advisor also saw that the chalk layer that the grower used to prevent too mellow temperatures in the summertime blockade out too much light source . " Sometimes Teun did not reach his required daily PARlight total because of this . In short : there is still a lot to be optimized in terms of light point in the glasshouse . "
ExperimentThe challenge now is to put the acquired additional knowledge and information into practice . In other words : does Valstar now dare , free-base on the information about the light content , to screen less and to allow more light into its greenhouse ? " This yr I ’m going to experiment with this , " say the raiser . " In any slip , I desire to utilize a less dense layer of chalk than before and also endeavor to allow in more natural PAR light , both momently and cumulatively . I am very hopeful that this will ultimately lead in a higher cultivation amphetamine and quality gain . "
For more informationTeun Valstar[email protected]www.teunvalstar.nl
