VPD is the force with which the air pulls water out of the leaf. Not humidity, not temperature, but their combination, and it explains why a well-watered tree closes its stomata and stops growing its fruit within two hours. With a calculator, the acceptable ranges, and what to do when they are exceeded.
The vine stops lifting water while the soil is wet. Root density, a 2% intercellular space and the five-hour oxygen rule explain why kiwifruit is the extreme case.
Water is withheld only while the pit hardens and the fruit is not growing. Why it works on late cultivars, why it costs size on early ones, and how the stress is actually measured.
On stone fruit the species is Phellinus tuberculosus, not P. igniarius. It lives inside your own orchard, enters through pruning wounds and works for years before the bracket appears.
Salinity, nitrogen and soil calcium, the three points where persimmon growing does not forgive. With documented limits, planting distances, nutrition, diseases and postharvest. Doses in kg/ha.
The single most important step is cultivar choice: it must suit the district and must not be susceptible to Sharka. The suggested spray programme by phenological stage, fertilisation, and the practices that decide the year.
Twenty-one modern apricot cultivars, one by one, from orchards followed in Pella, northern Greece. Breeder datasheets and field observation are kept strictly apart, and where they disagree both are given. Why resistant, tolerant and susceptible are three categories and not two, and why the absence of sharka symptoms is not the absence of the virus.
An aggressive disease that can take more than half the crop. The correct name of the pathogen, overwintering inside the dormant buds and why that load can be measured, the brown apical necrosis and vertical oozing canker forms, the per-tree risk scale counted in June, and the prayer-stage timing that is usually missed by ten days.
Quantity and size are inversely related, and size is decided at pruning: above 200 square centimetres of leaf area per fruit, about five leaves per cherry. Why double fruit are made the previous summer above 30 degrees, and why 20 ppm of gibberellin beat 30 ppm.
A season-by-season manual for the sweet cherry orchard: the sprays that matter month by month, what the research says about rain-induced fruit cracking, and fertilisation programmes by variety, rootstock and tree age, with every rate given per hectare.
Phytophthora, or crown rot, is a serious problem for agriculture worldwide, because beyond the crop it destroys the planting itself, which in tree fruit takes years to build again.
Ten paired leaf and soil analyses on holdings in three districts, over 10 July to 20 August 2020. In seven of the ten orchards the leaves showed nitrogen deficiency while every soil analysis reported sufficiency. The sufficiency thresholds, the trace-element findings, why soil and leaf disagreed, and what the survey cannot show.
