In the pilot cultivation fields of the 5 selected tulip species, a comparative study is carried out with the application of conventional agrochemical fertilizers and the application of precision fertilizers (foliar spray or root watering). The latter are nutritional schemes that include organic plant extracts of special composition produced by the company THEOFRASTOS with amino acids, sugars, B vitamin complex, nitrogen (non-nitrate, nitrite and ammonia ions), organic calcium and alternative sources of calcium.
The propagation and cultivation protocols under development apply precision fertilization (liquid organic fertilizers) of the company THEOFRASTOS. These fertilizers contribute to the reduction of inputs, production costs but also to the protection of the environment, mainly aiming at: (a) improved plant nutrition only with precision organic foliar fertilization, without burdening the soil and groundwater with conventional inorganic agrochemical fertilizers; (b) precision nitrogen fertilization, without burdening the soil with nitrate, nitrite and ammonia ions; (c) increased plant health and resistance to pests and diseases.
In the absence of knowledge about the nutritional needs of the selected species of Greek tulip, the combinations of THEOFRASTOS formulations were determined based on existing experience, observations taken during plant acclimatization in man-made environments and measurements of macro- and micronutrient uptake by plants. Specifically, the fertilizers used in various forms (foliar, root watering) were the following :
• THEOCOPPER (1.4% Cu, 12% N, 2.5% K, 3.5% organic matter, amino acids, sugars and vitamins)
• THEOCAL (30% organic Ca and 35% organic matter)
• THEORUN (17% N, 3.2% organic matter, amino acids, sugars and vitamins)
• THEEOFAST (100% from plant extracts and 4.4% organic matter)
• THEOVITA (17.4% organic matter, B vitamins)
• THEOMASS (100% from plant extracts and 5.4% organic matter)
The fertilization schemes (different for each treatment) were applied on a weekly basis in the two pilot fields (IPBGR and EPANOMI) until the completion of the biological cycle of the plants (drying of aboveground leaves). The foliar application was done with the use of hand sprayers of a capacity of 5 L, while the soil fertilization was done by root irrigation with the help of a dosing pump (Tefen MixRite 2.5 0.4%-4%).