Walnut Nursery Saplings have very important values in determining the suitable climatic conditions for growing, taking into account the walnut structure and fruit development. The walnuts are cold enough to satisfy the need for cooling in winter and spring (below +7.2 C); (25-35C) to provide normal growth and maturation in spring and summer. Coldness in walnuts; It is necessary to pass under (+7.2) C in the winter. One of the most important factors limiting walnut cultivation in a region is late spring frosts. It is frequently observed that the female flowers formed on the shoots of that year are damaged by late spring frosts. It is reported that not only female flowers but also male flowers are damaged from late spring frosts.
In addition to spring late frost damage, fall early frost damage can be counted as a factor limiting walnut breeding. It is also an important fact that ripening shoots are damaged by early autumn frosts because the length of vegetation is short in very late leaf walnut varieties.
Young and strong developing walnut trees can be damaged in the winter months because they will be late to rest. Factors such as the degree of low temperature, falling speed, and duration play an important role in the damage from cold.
Also, some years of extreme winter colds can cause significant damage to walnut tree shoots. Mature healthy walnut trees can withstand temperatures between -15 ° C and -20 ° C in the winter months.
The walnuts can last up to -1 C for 30 minutes in the period when the buds are closed but colored. It is stated that the walnuts are also damaged in the small fruit period after -1 ° C.
Another important climatic factor that determines the successful cultivation of walnut in one place is to meet the need for coldness. If this can not be met, the bud bursts can be significantly delayed and reduced in efficiency. For walnuts, a 200 to 1800 hours of cooling (less than +7.2 C) may suffice.
The temperature rise up to 38 ° C during the period of internal walnut development can cause dark spots, shrinkage in the walnut. In terms of walnut breeding, it is important that at least 500 mm of rainfall per year is sufficient and that this rainfall is regular.
Request for Soil in Walnut Growing; What ground of walnuts does it grow?
The walnut trees develop strongly and the roots go deeper in medium-thin textured clayey sandy and rich organic soils.
Clayey, spindle, pebbly silt layer, water accumulation and sand deposits, which limit root depth, may limit the developmental power and woodyness of walnut trees.
250-300 cm soil depth for walnut trees obtained by vaccination activities in Turkey is ideal. However, the intake of water and plant nutrients should not be compromised by a soil depth of 100-150 cm, which is approximately 75%.
High pH and Calcareous Soils; The appropriate pH value in the soil for growing walnuts is around 6. In order to keep the pH value at optimum level, the selection of acidic and basic fertilizers is taken care of. When the pH value is higher than 8, phosphorus, iron, zinc and boron may cause deficiency. In walnut farming, 5% active lime can cause iron chlorosis.
Before creating a walnut garden, we need to have soil analysis done in competent laboratories.
