Container Type and Overwintering Treatments Affect Substrate Temperature and Growth of Chanticleer® Pear (Pyrus calleryana ‘Glen's Form’) in the Nursery

Abstract

The container most used for nursery tree production is black plastic (BP). High substrate temperatures occurring in BP can injure or kill roots; BP-grown trees often develop circling and malformed roots. Root injury sustained during production may negatively affect tree health after planting in the landscape. Many containers are available for nursery production, but few studies have examined the merits of alternative container types for production. We compared the growth of Pyrus calleryana Decene. ‘Glen's Form’ (Chanticleer®) in three container types: black plastic, Root Pouch® (RP) and Smart Pot® (SP), over two growing seasons and under two overwintering treatments (consolidated or lined out). After the first growing season, there were no differences in height or dry leaf, shoot and root weight among the three containers. Following the second growing season, caliper, height, leaf area, percent leaf moisture, and root ball quality differed among container type. After the 2010–2011 winter, consolidated trees produced larger root and shoot systems (35.3 and 36.4%, respectively) than trees that were lined out. Substrate temperature maxima and fluctuations during winter and summer were greatest for BP containers compared to RP and SP. The potential advantages of producing trees in fabric containers merit consideration from nursery producers.