The cultivated varieties of sweet cherries are derived from wild-growing bird cherries (Prunus avium), which are common in Europe, Western Asia and the Caucasus.
The sweet cherry fruit is a drupe that can be yellow, red, to very dark red, almost black in color. Sweet cherries ripen from May to the end of July. The fruit is intended primarily for fresh fruit market, but is also used in the processing industry.
Sweet cherry is one of the most strongly growing species of temperate climate fruit trees. This is a feature that should be taken into account when designing an intensive sweet cherry orchard, especially when choosing a rootstock on which the tree’s growth strength depends. The selection of the rootstock should take into account the soil conditions of the farm and the climatic conditions of the region. Sweet cherry trees grafted on dwarf rootstocks produce a shallower root system, which makes them less tolerant of water and nutrient deficiencies in the soil.
Cherry is a species whose trees are moderately resistant to periodic water shortages in the soil. Therefore, it is very important to ensure optimal soil moisture and providing trees with the essential nutrients in the amounts needed for the proper development and growth of plants.
Irrigation systems enable adequate water supply to trees. Drip irrigation is especially effective. Drip irrigation system enables use of fertigation – supplying trees with nutrients supplied with fertilizers dissolved in water. Fertilizers recommended for fertigation must be of very high quality, especially excellent solubility in water, practically no insoluble parts and high concentration of nutrients – DROPFERT 18/18/18, DROPFERT 4/40/18, DROPFERT 9/10/36, MIKRO PLUS™, MIKRO PLUS™ ULTRA. For the fertigation of crops in the field conditions, you can also use universal fertilizers of PLONVIT® series: PLONVIT® OPTY, PLONVIT® NITRO, PLONVIT® PHOSPHO, PLONVIT® KALI.
Fertigation, although it is a very effective method of fertilization, does not eliminate the need to foliar nutrition. Its main advantage is the quick and effective supply of the most-required nutrients to trees at particular stages of development. Presently, foliar treatments are an integral part of the mineral nutrition programs for sweet cherry trees, because:
- support supplying plants with major nutrients: nitrogen (PLONVIT® NITRO or PLONVIT® NITROMAG), phosphorus (PLONVIT®PHOSPHO or PLONVIT® FOSTAR), potassium (PLONVIT®KALI or PLONVIT® KALPRIM), magnesium (MIKROKOMPLEX®) and sulphur (PLONVIT® SULVIT or PLONVIT® BOROSULF)
- provide plants with ingredients that are difficult to be taken from soil, e.g. boron (MIKROVIT® BORON TURBO or MIKROVIT® BORON)
- provide plants with ingredients that directly affect the fruit color and firmness, as well as the color, quality and strength of the fruit stalk: phosphorus (PLONVIT® PHOSPHO or PLONVIT® FOSTAR), potassium (PLONVIT®KALI or PLONVIT® KALPRIM), manganese (AMINO ULTRA® Mn-22 or MIKROCHELAT™ Mn-13 or MIKROVIT® MANGANESE)
- support supplying sweet cherry trees with calcium, which is a low-mobility nutrient in the plant (OPTYCAL®, PLONVIT® CALCIUM TURBO – calcium increases the flexibility of the peel, reduces fruit cracking and increases their shelf life in market trade).
In the cultivation of sweet cherries, large losses are caused by fruit cracking due to rainfall during fruit ripening and harvest – especially after periods of low soil moisture.
One of the methods of reducing cherry cracking is spraying trees with a solution of calcium fertilizer (PLONVIT® CALCIUM TURBO). There are recommended standard spraying each time directly before the expected rainfall or during rainfall.
Sweet cherry is a crop that requires proper care after fruit harvesting, i.e. in the period from the end of harvesting to the end of vegetation in autumn (for a period of about 3–4 months).
- The first goal of these treatments is to keep the leaves in good condition on the trees, because premature defoliation or damage to the leaves caused by diseases and pests or nutrient deficiencies leads to tree weakness, a decrease in their resistance to frost and a significant reduction in yield.
Therefore, after harvesting cherries, fertigation should be continued for 1–2 months – depending on the date of harvesting the fruit.
At that time, an NPK nutrient solution with a significant predominance of phosphorus and potassium and a low nitrogen content, enriched with micronutrients (DROPFERT™ 4/40/18, DROPFERT™ 9/10/36, MIKRO PLUS™ or MIKRO PLUS™ ULTRA) is recommended.
It is also advisable to supply magnesium by foliar treatment as the fastest way to supply trees with this nutrient, which influences the photosynthesis process (MIKROKOMPLEX™).
The foliar treatments with the use of copper products (MIKROCHELAT™ Cu-15) are also used to increase tree resistance to diseases.
- The second important goal is to enable trees to accumulate nutrients needed for their development in early spring.
In spring, low temperature limits the effective uptake of nutrients from the soil. Therefore, before the beginning of leaf color turning, trees should be foliar fed with fertilizers containing zinc and boron (BORZIN TURBO™) and potassium (PLONVIT® KALPRIM or ALKALIN® K+Si). These treatments are the first ones to prepare trees for the new growing season.
The good condition of sweet cherry trees throughout the growing season determines the yield of sweet cherries.
Even short-term nutrient deficiency may have a negative impact on plant growth and yield. Therefore, it is necessary comprehensive assessment of the requirements of the plants at any stage of their development. This will allow them to be properly fed and biostimulated. INTERMAG’s wide range of products, allows you to develop your own individual foliar fertilization and biostimulation program, considering local soil conditions, crop intensity, stage of plant development and availability of various products.
Particularly noteworthy are the highly alkaline line of fertilizers ALKALIN™, which, in addition to the basic functions of bringing in nutrients, have shielding properties for plants: ALKALIN™ K+Si, ALKALIN™ KB+Si, ALKALIN™ PK 10:20.
All of these discussed actions significantly affect the yield increase and its quality parameters.
