Autumn Is the Planting Season, Not Spring
Warm soil and reliable rain do most of the work for you. Spring planting means a summer of watering.
Garden centres are busiest in April, which is roughly six months after the best moment to plant almost anything.
Roots Grow When Soil Is Warm
Soil holds its summer heat well into November. A shrub planted in October puts on root growth through autumn and again from late winter, so by the time it has to face a dry June it is already anchored. The same plant put in during April has had six weeks of root growth and a full summer to survive on it.
The Rain Does the Watering
Autumn planting is watered by the weather. Spring planting is watered by you, every few days, for an entire season, and the first hot fortnight you go away is usually when you lose things.
The Exceptions
Anything tender or Mediterranean — lavender, rosemary, salvias — genuinely prefers spring, because sitting in cold wet soil all winter kills more of them than drought ever does. On thin limestone this matters less than it does on clay, but the rule holds.
Bare Root Is the Real Prize
Hedging, roses and fruit trees are available bare root from November to March at a fraction of the container price, and they establish better. A hornbeam hedge planted bare root costs a quarter of the potted equivalent and overtakes it within two seasons.
