I have visited what I understand is France’s second largest tomato growing area at Berre Etang, just across the big bay from the Marseilles Airport at Marignane. Here under a hectare of glass I tasted some of the finest tomatoes one could possibly imagine. Although the facility is in France, most of what I saw appears to be Dutch technology that is being exported throughout Europe and around the world. The French operation has been in tomatoes for many years, only recently has it instituted this “high tech” approach.
The plants come in the fall and are started when about 21 inches high. The big tomatoes are a Dutch variety (“Harmony” ) that ensures each fruit on a stalk (called here a “grape”) is the same size. This is important because most tomatoes and other fruits (tomatoes are called fruits here, not vegetables) usually have what is called a king or queen bud that blooms first. This generally produces a fruit bigger than those that come later. The fact that all are the same size means that one can see in the local market a remarkable group of tomatoes. The fact that they are all still attached to the same stem gives the impression they are vine ripening before one’s eyes. The operation grows cherry tomatoes as well, but the greenery is not sold with them. For taste, however, I prefer these smaller tomatoes.
The greenhouse is hydroponic; the plants are given nutrients in water that is fed to them via plastic pipe drip irrigation under computer control. Readings are taken throughout the day to verify that the correct amounts are being supplied and taken up by the vines. The climate inside the greenhouse is also carefully controlled.
The plants I saw are now (first part of June) six meters high. Most run along the ground for some period and then begin a lazy climb into the stratosphere of the greenhouse. If ever one wanted to imagine Jack ascending his fabled beanstalk, these succulent tomato vines provide just the right picture. On the vertical portion the, grapes come off at equal intervals. Each plant at this time has about 25 bunches (grapes) of tomatoes (5 to 7 fruits to a grape). It is expected that later in the season there will be as many as 42 bunches per vine.
Greenhouse technology is far ahead of outdoor plantings because more variables can be controlled. These tomatoes are advertized as hand picked; a truck runs on plastic tubing rails down the rows easily pushed by workers selecting and cutting the ripening grapes; weather never intervenes to prevent the harvest. This operation is also aware of pesticide costs and benefits; these materials are used very sparingly if at all. The operative words here are “pest management” and “biological control.” As part of this philosophy, consultants and or technicians inspect the vines on a routine basis, even donning wooden stilts, so they can observe the fragile tops of the plants. The whiteflies and other feared tomato-eating insects are here of course, but not in great numbers that might be expected in so an intensive a planting. Through constant vigilance, incipient invasions of herbivores, fungi and bacteria are caught early and eliminated without use of expensive chemicals. In any agricultural enterprise this may be as close to “organic” (called here “biologique”) as one can get.
The goal of the grower is not elimination, but the quest to keep populations of insects and other pests (bacteria, fungi) down to a reasonable level. In pest management parlance, this is called keeping pests below the economic threshold. The evidence of one such effort is a small paper card with insect eggs glued to it. Some of these are just shells; the residents have already emerged; releasing predatory wasps to parasitze plant feeders. This is one of many attempts to imitate the natural balance of things in a human controlled and patrolled environment.
Besides the efforts in plant nutrition and pest management, greenhouse technology has taken another step toward to future. It is giving pollination its due, treating it just like any other agricultural input. Again, this is subtle, for only occasionally does one see a lone bumble bee lazily make its way among the blooms. There aren’t many blossoms here, but each needs a maximum amount of attention for no single bloom can afford to go unpollinated in this intensive environment. This would seem the perfect environment for Bombus. Bumblebee nests do not have the numbers of individuals that must be supported as does a honey bee colony and the insects not are not as driven to produce for their sisters. There is little wind in the greenhouse; bumble bees produce their own through vibrating the bloom, causing the precious pollen to be liberated. This is something honey bees despite their increased number do not do effectively.. Finally, Bombus is not as disoriented in the naturally lighted greenhouse as is its Apis cousin. Overall, the tomato grower gets the biggest pollinating effort per insect using Bombus. The specific insect used is Bombus Terrestris.
Tomato pollination is not problem-free using bumblebees. Because a constant supply of the insects is necessary over an extended period of time, the bee colony tends to be loose population. And in the fall, the whole thing collapses as would be expected of any insect that has an annual cycle. Thus, there is the need for the consultant to periodically determine and perhaps invigorate the pollinating effort. In this French operation, nests are inspected and some replaced every week or so. This does not come cheap and requires a special approach that so far seems to have eluded the French beekeeper.
Just outside of Aix-en-Provence, one beekeeper who tried rearing Bombus, and was very good at it, has thrown in the towel and gone back to hisApis charges with renewed passion. One of his concerns was that the bumblebee market had also dropped to a level where it was just not economically feasible to produce the bees. In the beginning, before there was much competition, the prices were much higher.