Planter Size Guide: Minimum Volumes for 40 Common UK Garden Plants

Furniture in Fashion's 2026 planter guide argues that container size is the single largest control a gardener has over performance on a UK patio, balcony or terrace, because it governs root volume, water reserve and thermal stability. Rather than publish litre requirements for named species, which no verified dataset available to us supports, the guide teaches sizing by root behaviour: fibrous rooted bedding and salads want surface area at around 20 cm to 25 cm depth, fruiting crops need 30 cm to 40 cm for water reserve, and shrubs, climbers and small trees need 40 cm to 50 cm or more for both roots and ballast. It explains why small pots fail in short dry spells, since water reserve scales with volume while loss scales with leaf area, and why grouping containers reduces both stress and workload. Weight when saturated, unobstructed drainage and material behaviour complete the practical picture for balconies and decks....