The management of botanical collections involves various terminologies, such as "accession" and "plant material." In the context of garden collection management, it is important to understand the distinction between these two concepts.

This article aims to elucidate the key differences between accessions and plant material and their significance within botanic garden collections.

Accession

An accession refers to a distinct entry into the collection, representing an individual (or group of) plant material belonging to a single taxon with identical parentage, acquired from one source at the same time. It is a standardised record that includes essential information such as the scientific name, provenance, source (donor or supplier), date of acquisition, and other associated data.

Upon acquisition, an accession is assigned a unique accession number, which enables efficient tracking and retrieval of information related to any associated materials (see below). In Hortis, the standard format for accession numbers is YYYY-####, where "YYYY" represents the year of acquisition, and "####" denotes a unique numerical identifier.

The accession numbers are typically assigned sequentially as new plants are added to the collection, ensuring each accession has a distinct identifier for efficient tracking and reference purposes.

Plant Material

Plant material refers to the living or preserved parts of the accession, such as seeds or living plants. Plant materials are directly linked to a specific accession, and are given individual qualifiers that can be alphabetic (/A, /B, /C) or numeric (/01, /02, /03). The qualifiers help categorise and distinguish different parts or forms of the same accession, allowing for precise tracking and documentation.

A plant material record will include data on when it was planted, its status, quantity, location in the garden, and associated information. Plant materials can be tracked individually or as a group, depending on the desired level of detail for tracking and mapping.

For example, a single qualifier may be associated with a single individual plant, such as a large woody tree, with a quantity of 1. Alternatively, a qualifier can represent a group of individual plants, such as a cluster of herbaceous perennials, with a quantity of 5.