How many cucumbers can growers harvest in one year from one square meter in the greenhouse? This question keeps growers and breeding companies busy, as can be derived from the continuous development of varieties.
"Yet ultimately, it is mainly the number of kilos that come from a square meter that the grower can really do something with," is the opinion of Joop de Hoog, former chairman of cucumber grower organization Friskom. With his large network, many growers still ask him for advice. "You can only make good calculations and compare them based on the number of units and kilos per square meter."
During his time as Friskom chairman, Joop kept a close eye on both sales figures and energy prices. “Certainly when the auction in Pijnacker still existed, I received a summary twice a year of what each cucumber grower had supplied on the clock in terms of units, assortment and monetary revenue.
"And these I linked to the energy figures, which I requested from the energy companies with the growers' permission. That way we could calculate the production in kilos, as well as the gas consumption per harvested kilo of cucumbers. We then discussed the figures in the fall, anonymously without the names, in order to get a picture of what a cucumber crop yielded for the grower and to see what could be causing the differences."
When it comes to calculation, Joop is still at it. Labor should also not be forgotten in those calculations. “Certainly growers who started high-wire cultivation have seen their labor costs rise, even though labor is also a problem in traditional cucumber cultivation with three or four cycles. Labor is the highest cost item and if I hear the stories that circulate, labor costs per square meter will again increase by two euros this year.”
So not all that glitters is gold, according to Joop, who is not yet fully convinced of high-wire cultivation. “According to my calculations, growers with high-wire cultivation will have to spend ten euros per square meter per year more, compared to traditional cultivation in three or four cycles.
"It is good, therefore, that in recent years a few of them have abandoned the high wire and did so out of practicality. According to me, growers should talk about that more often in excursion groups.”
Growers are all enormously resourceful, according to Joop. "When a grower even talks a bit about labor in a conversation, it is the right time to respond to that and to get that grower thinking."
For example about robotization, which was also tested in the past. “With rising labor costs, that will become increasingly more appealing, although a lot still needs to be done for it to really work. There is still work to be done in both cultivation and breeding.
"It is important, for example, not to screw in too firmly to ensure that the fruit stays hanging to the front of the stem, although it would be great if in the long term varieties could be adapted in breeding to automated harvesting.”
In addition to growing on the high wire, also lighting has entered cucumber cultivation. “For growers with lighting, whether it's SON-T or hybrid, you can calculate exactly what they will harvest on an annual basis. With 15,000 lux of light above a crop, for 20 hours you end up with around 7 to 8 cucumbers per square meter. If you do that all year round, you end up with around 350 cucumbers per square meter per year, including crop changes, but then you must always have the same light above your crop.
"And, not unimportantly, take into account the municipal rules on lighting. I think that is sometimes done too casually, especially in view of the public resistance to light pollution.”
What else can be added?
According to Joop, in cucumber cultivation without supplemented lighting, the top of the Netherlands produces around 190 to 200 units of cucumbers per year, which comes down to around 90 kilos per square meter, including some crooked cucumbers. “It's hard to imagine if those numbers could still go up. Perhaps there will be new varieties with, for example, smaller leaves, so that fruits will receive even more light, although I do wonder how active those leaves will have to be to continue producing."
With lighting, the next challenge is to earn that extra cost from an exposed crop back when selling. “Where in tomatoes large parts of the crop are sold under contract, that is hardly ever the case in cucumbers. To keep investing as a cucumber grower, that clarity about the price he or she will receive is certainly welcome."
In addition to following the cultivation, Joop also regularly takes a look at the store shelves. “When recently I walked through the supermarket, the quality of the Spanish sealed cucumbers gave me a bit of a start. And I found it disappointing that no Dutch cucumbers were for sale."
The production in the Pijnacker region is gradually getting under way, Joop noticed. “In week 9, growers barely reached 1.5 to 2 cucumbers per square meter. That is not much, simply due to a lack of light and therefore little growth rate in the crop.
"That is reflected in the prices, the daily price has skyrocketed, presale on an annual basis is still limited in cucumber. The 40 cents was replaced by 60 cents at the clock on February 27, and then those 40 cents are hardly available." The prices are now better than around this time last year. "But at that time the prices were really bad."
For the rest of the season we have to wait. “In terms of growers switching from tomatoes, as was feared here and there, luckily this was not too bad. A few might have done so, but that won't be the problem. But it remains exciting anyway, especially now with little light. A challenge for the grower who has to choose which 24-hour temperature he will maintain on the one hand to keep the crop well and on the other hand to have production."