"Opal stands out as a premier early plum variety, often referred to as a gage-like plum due to its outstanding flavor. This characteristic, shared with Ariel, underscores the enhancement of gage-like taste achieved by crossing a gage with a plum. The delectable flavor, however, hinges on the crucial development of sugars during the brief growing period. In the UK and northern Europe, cultivating Opal against a south-facing wall or in a sunlit location significantly enhances its flavor. While it still yields good crops in less favorable conditions, the taste may lean towards the bland side. The medium-sized fruit features a dusky red hue with a dense bloom, transitioning to a blue shade when overly ripe. Optimal flavor is attained just before the color shifts to blue. The ripening process spans approximately 1-2 weeks, preventing an overwhelming abundance of plums. The straw-yellow, fairly juicy flesh of Opal is easily separated from the stone, making it a free-stone plum. When picked on a warm July day and displayed in a fruit bowl, Opal emits a delightful aroma. Recommended for its adaptability to various climates and the provision of high-quality plums early in the season, Opal thrives when the crop is thinned, and it is planted in a sun-drenched location to unlock its full flavor potential."