The research was carried out in a commercial apple orchard in southeastern Poland. The aim of the research was to evaluate the effect of fertilizer with biostimulation and humic acids with algae extracts and agrogel on the reception and growth of newly planted maiden apple trees of the ‘Gala Must’ variety. One-year-old budwoods were planted annually on the site where fruit trees had grown for 20 years. For the purpose of the experiment, old trees were grubbed up every year in autumn. The experiment assessed the growth and quality of apple trees in the fall of the first year after planting them permanently using a biostimulator in the form of fertilizer and agrogel. On the basis of 3-year studies, it was shown that the application of the assessed preparations had a positive effect on the quality parameters of the trees. The experiment showed the positive effect of the preparation with biostimulation on the best growth and quality parameters every year, which was confirmed by the multidimensional cluster analysis. The fact that the use of agrogel significantly modified the height of the evaluated apple trees in the second year of the study, when lower amounts of rainfall were recorded, is particularly noteworthy.

A field experiment was carried out in Felin Experimental Farm (2019) in Lublin region (Poland) in order to determine the effect of white mustard (Sinapis alba L.) seed meal (MSM) on weed density as well as on borage plant growth and yield under field cultivation. MSM scattered on soil surface at rates of 2 and 3 t ha−1 when weeds emerged and a day before emergence of borage did not affect the number of borage seedlings but caused transient growth stunting and chlorosis of cotyledons and first leaves. However, final plant height, yield of above-ground parts, mericarp dimensions and weight, content of oil in mericarps, and oil composition were not significantly affected by MSM treatment. At harvest, MSM had decomposed completely, supplying considerable amounts of phosphorus, potassium, and magnesium to the soil, but did not affect its pH or organic matter content. MSM suppressed weed density by 37%–46% during the period of highest sensivity of borage to weed competition. Among dominant weeds occurring in the experiment, Gnaphalium uliginosum and Stellaria media were the most susceptible to MSM, while Amaranthus retroflexus and Galinsoga ciliata were mildly susceptible, Echinochloa cruss-galli and Poa annua were less susceptible, and the least susceptible species was Capsella bursa-pastoris. Obtained results show that MSM may have value for early season weed suppression in borage cultivation.

Peppermint (Mentha ×piperita L.) rootstock cuttings with 9–11 internodes were planted on April 10, 2014 in rows 50 cm apart and with 25-cm distance in the row, on well fertilized muck-peat soil containing 82.1% of organic matter with a pH of 5.9. Peppermint plants were sprayed once with an activated EM-1 preparation, then on two or three further occasions as follows: at 10 cm height (May 10), at branching stage (May 29), and during rapid growth (June 19). EM did not affect peppermint growth or yield. Yields of the fresh and dry herb were high (means: 15,563 and 2,661 kg ha−1, respectively) and characterized by a medium (1.85–1.90%) essential oil content in the dry herb. Twenty-nine compounds were identified in the oil and its main components were menthol (53.1–58.5%), menthone (14.6–16.8%), isomenthone (6.3–6.7%), menthyl acetate (4.0–5.0%), germacrene D (2.3–3.4%), ß-caryophyllene (1.8–2.4%), viridiflorol (1.5–2.3%), and 1,8-cyneole (0.3–3.7%). EM did not affect the content of essential oil in the dry herb or the oil composition (except for 1,8-cyneole). Thirty-four days after planting, 22 weed species grew in the experimental plots and the dominant were common meadow grass (Poa pratensis L.) accounting for 20% of total weed population, annual meadow grass (Poa annua L.) 17%, common chickweed [Stellaria media (L.) Vill.] 20%, creeping yellowcress [Rorippa sylvestris (L.) Besser] 8%, hairy galinsoga [Galinsoga ciliata (Raf.) S. F. Blake] 7%, gallant soldiers (Galinsoga parviflora Cav.) 6%, Canadian horseweed [Conyza canadensis (L.) Cronq.] 6%, common groundsel (Senecio vulgaris L.) 5%, and annual nettle (Urtica urens L.) 5%. Other species occurred sporadically. The total number and fresh weight of weeds growing on 1 m2 were 412 and 246 g on plots treated with EM and 389 and 227 g on control plots, respectively, but the differences were not statistically significant.

In the first two years of study, method of cultivation did not affect the emergence of cucumber seedlings. In the third year, a drought occurring during the spring was the cause of poor seedling emergence on no-tilled plots. Six weeks after seed sowing, the shoots of cucumbers grown on the no-tilled plots were much shorter, especially in the last study year. At the time of cucumber seed sowing, no-tilled soil contained less phosphorus and potassium and in the middle of the fructification period the content of these elements in cucumber leaves was higher under no-tillage cultivation. Additional spring fertilization of rye with ammonium nitrate resulted in a higher N-NO3 content in soil and later in a higher nitrogen content of cucumber leaves. The content of calcium and magnesium in soil and than in cucumber leaves was independent of the cultivation method. In the first two years, method of cultivation did not affect the yield of cucumber fruits and in the third year the yield was much lower under no-tillage because of poor seedling emergence. Moreover, in the third year the fruits were smaller and dry matter content of the fruit was significantly higer under no-tillage cultivation.