When to plant Common juniper?
Best month and method — Juniperus communis
Plant your common juniper in March, April, September and October — the optimal month is usually September.
The next planting window is September.

Spacing
150 cm
≈ 1 plant
For an X m² border, calculate: X × 1 plants.
Step by step: plant common juniper
Common juniper thrives in full sun and tolerates a wide range of well-drained soils, including sandy, loamy, and chalky ground. It dislikes waterlogged conditions, so avoid heavy clay unless you can improve drainage significantly. The best planting times are March and April in spring, or September and October in autumn, when the soil is still workable and the plant can establish roots before temperature extremes arrive. Choose a spot with plenty of space: mature specimens can reach 1–6 metres tall and spread 1–3 metres, depending on the variety. If planting more than one, space them at least 150 cm apart. Dig a hole roughly twice the width of the root ball but no deeper—junipers should sit at the same level they were growing in the pot. Break up compacted soil at the base and sides of the hole to encourage roots to spread. Place the plant in the hole, backfill with the excavated soil mixed with a little garden compost if your ground is very poor, and firm gently to eliminate air pockets. Water thoroughly after planting to settle the soil around the roots, even though common juniper has low water needs once established. A 5 cm layer of mulch (bark chips or gravel) around the base helps retain moisture during the first season and suppresses weeds, but keep it a few centimetres clear of the stem to prevent rot. Staking is rarely necessary unless you're planting in an exposed, windy site. Container-grown plants establish more reliably than bare-root specimens.