Articles
NITROGEN FERTILIZATION IN INTEGRATED OUTDOOR STRAWBERRY PRODUCTION
In comparison there is very little scientific data from field-trials on the nutrition of outdoor plantings.
Central interests are concentrated on nitrogen, which is easily leached out by rainfall.
Modern strawberry cultivars may demand less nitrogen than traditional ones.
Compared with other field-crops strawberry plants have a limited root-system, concentrated in the upper soil layer.
The use of split applications of the annual nitrogen input by means of row applications at different times is important.
In trials foliar applications of urea (0.3%) had a positive effect on the development of strawberry plants on poor soils.
Nitrogen fertilizing did not increase the fruit yield of June-bearing cultivars on soils with medium nutrient reserves.
Firmness and shelf-life of strawberry fruit decreased with increasing nitrogen supply.
Mulching techniques in strawberry plantations influence soil temperature, water and nutrient contents.
Under black polyethylene film temperature and nitrogen availability were higher than in uncovered soils.
In plantations with a straw-mulch applied after planting, nitrogen uptake was reduced in the following spring.
Strawberry growers need reliable field-methods to assess the available soil nitrogen as well as the nutritional state of the strawberry plants.
Analysis of mineral nitrogen content in active and warm soils (after planting, at blossom time) provides useful information, whereas the analysis of total nitrogen content in plant dry matter was difficult to interpret, nitrate-leaf-tests correlated well with the nutitional state of strawberry plants.