Gentiana saponaria and Gentiana andrewsii are two species of plants that belong to the Gentiana genus. While they may share some similarities, there are also distinct differences between the two species.
One noticeable difference between Gentiana saponaria and Gentiana andrewsii lies in the structure of their corolla plaits and lobes. In G. saponaria, the corolla plaits are narrower than the corolla lobes. This means that the folded sections of the corolla are narrower in width compared to the lobes of the corolla. On the other hand, in G. andrewsii, the corolla plaits are wider than the corolla lobes. This means that the folded sections of the corolla are wider in width compared to the lobes.
Another difference between these two species is the reliability of a specific character mentioned in most manuals. It is often stated that in Gentiana saponaria, the corolla tube is slightly open at maturity. However, this character is not always reliable and may not be a consistent distinguishing feature between the two species. This highlights the importance of considering multiple characteristics when identifying these plants.
In my personal experience with these species, I have observed that G. saponaria tends to have a more compact growth habit compared to G. andrewsii. The foliage of G. saponaria is typically denser and forms a more rounded shape, while G. andrewsii may have a more sprawling or open growth habit. Additionally, the flowers of G. saponaria are often a vibrant blue color, while G. andrewsii flowers can range from pale blue to purplish-blue.
When it comes to cultivation, G. saponaria and G. andrewsii have similar requirements. Both species thrive in moist, well-drained soil and prefer full sun to partial shade. They are also known for their preference for cooler climates and are often found in alpine or mountainous regions. In my garden, I have found that providing these plants with consistent moisture and a slightly acidic soil pH has resulted in healthy growth and abundant flowering.
To summarize, Gentiana saponaria and Gentiana andrewsii have distinguishable differences in the width of their corolla plaits and lobes. While G. saponaria has narrower plaits, G. andrewsii has wider plaits. The reliability of the slightly open corolla tube character in G. saponaria is questionable. Additionally, G. saponaria often displays a more compact growth habit and vibrant blue flowers, while G. andrewsii may have a more sprawling growth habit and flowers ranging from pale blue to purplish-blue. Both species have similar cultivation requirements and thrive in moist, well-drained soil with partial sun to full shade.
