The interest in cultivation of vegetable soybeans, also known as edamame, in the North Europe region has increased during the last years due to their high nutritional value and excellent taste properties. During the last decade the possible growing area for soybeans has expanded towards the north due to changes in climate as well as breeding efforts. In order to adopt vegetable soybean growing technology for commercial cultivation in the North Europe region, independent experiments were carried out in Latvia and Norway. This study shows that vegetable soybean is a crop with potential for successful cultivation at higher latitudes, such as the Nordic–Baltic region in North Europe, with yield levels comparable to other regions of the world. We observed that hydrothermal conditions had the most significant impact on soybean plant development. Sowing or planting as early as possible is a key to obtaining sufficient yield levels. In the study, the vegetation period needed to be at least 123 to 127 days, with growing degree days (GDD) at least 650, and hydrothermal coefficient (HTC) above 1. Under such conditions, the obtained marketable yield in Latvia ranged between 3 to 10 t ha⁻¹ during the period of 2017–2019, and 1.2 to 10.5 t ha⁻¹ in Norway. Planting density of 20–25 plants per m² appeared to be optimal. The variety ‘Midori Giant’ showed the most stable yield outcome, but ‘Chiba Green’ also gave a satisfactory yield.

Different vegetables are a good source of essential components for human food. Consumers are more and more aware of a healthy and balanced diet. Vegetables usually contain natural antioxidants which neutralize free radicals in the human body. The composition of biologically active compounds in plants is depending on the climate and growing conditions, cultivar properties, plant development stage, harvesting time, and other factors. The aim of the research was to evaluate the fluctuation of antioxidant activity in leaves of four common nettle (Urtica dioca L.) clones and three garden orache (Atriplex hortensis L.) varieties during vegetation period in Latvian conditions. Experiments were carried out in open field conditions in the Pūre Horticultural Research Centre during the vegetation period of 2014, in two soil fertility variants for nettle and two sowing periods for garden orache. Antiradical activity was determined using the 2.2-diphenyl-1-picrylhydrazyl radical (DPPH*) method. In nettle leaves, antioxidant activity ranged between 17.31–80.77 %, depending on soil fertility, nettle clone and plant age, and in orache leaves between 17.9–54.0 % depending on variety and sowing time. In nettle leaves, the antioxidant activity at the beginning of the vegetation period ranged between 31.0–62.7 %, the highest activity was observed at the stem elongation stage (75.5–78.5 %). A higher antiradical activity was detected in the control variant (without compost treatment) at the 3–5 and 7–9 leaves stage. In other development stages, better results were obtained in the fertilized variant where compost and peat were used as an organic manure. Differences were found also among clones, especially in the 3–5 leave stage. Significant differences for garden orache leaves were found between sowing times. In the first growing period the antiradical activity ranged between 46.1–54.0 %, in the second it was two times less.DOI: http://dx.doi.org/10.5755/j01.ct.66.1.12055

Optimizing nutrient uptake efficiency (NUE) through an understanding of system-level dynamics and crop-specific physiological thresholds is essential for the resilience of North European vegetable production under shifting climatic conditions. This study evaluated the uptake and efficiency of macro- and secondary nutrients (N, P, K, Ca, Mg) in cabbage, carrot, red beet, and onion over a five-year period (2021–2025) in Latvia, comparing organic and integrated management systems. It was hypothesized that NUE on commercial farms is currently suboptimal due to standardized bulk applications and that systems integrating sustainable practices would demonstrate higher nutrient uptake efficiency than those relying exclusively on mineral fertilization. The results revealed a notable yield–input divergence, where increased fertilization rates failed to provide proportional yield gains, as evidenced by the lack of a strong linear relationship (R² < 0.07) and variable correlation coefficients (e.g., r = 0.52 for N in cabbage and r = −0.47 for Ca in carrot). These findings suggest that abiotic stressors and technical constraints may outweigh the influence of nutrient volume alone. This divergence was less pronounced in organic farming systems compared to integrated ones and varied notably by crop. Such species-specific responses indicate a complex role for mineral nutrition in root crops that requires further physiological investigation. No consistent differences in nutrient concentrations were observed between farming systems, indicating that inter-annual climatic variability is the dominant driver of nutrient dynamics. Furthermore, the integration of green manures and supplemental irrigation triggered extreme apparent system-level N-NUE values (exceeding 500% in some cases), reflecting the successful mineralization of legacy nitrogen and enhanced mass flow to the root zone. The study concludes that current fertilization methodologies in the Baltic region may lead to over-application. To ensure climate-resilient horticulture, management strategies must transition toward balancing ionic ratios (Ca:K) and synchronizing inputs with specific crop removal rates, rather than relying on standardized bulk applications.

Urban horticulture has become an increasingly vital part of sustainable food production systems, offering ways to improve food security, cut down on food transport distances, and foster environment...