Oenothera 'Innoeno131' LEMON DROP sundrops, evening primrose
Oenothera
Evening primroses have been cultivated in Czech gardens for generations. These are mostly drought-tolerant plants native to North America, the southwestern USA, and Mexico. I fondly remember a species with large yellow flowers, which we would visit as children every evening – watching them bloom right before our eyes in just 5–10 minutes. They remained open only through the night. Despite their names in many languages hinting at nighttime blooming, some evening primrose species actually bloom during the day.
The Genetic Puzzle of Evening Primrose
Botanically speaking, evening primroses are tricky due to their unusual genetic behaviour, which complicates classical Mendelian inheritance patterns – exactly the type of mystery botanists love to unravel. Determining the precise species or parentage of cultivated varieties is almost an impossible task. Take Oenothera lamarckiana, for example – studied by Hugo de Vries, it became key to mutation theory, since its genetic variability suggested that new species could emerge suddenly, like lightning out of a clear sky, rather than through gradual evolution (Darwin wouldn’t be thrilled about that!). In other words, if we come across a beautiful evening primrose with unique traits, let’s just be happy it exists and not obsess over its genome – deal? 😊
LEMON DROP as an evening primrose variety is the perfect example of a mysterious origin – its narrow leaves, compact growth, and brilliantly coloured flowers have no clear botanical explanation. But who cares? It’s simply irresistible! This low-growing variety has a sprawling habit, similar in height and growth style to Oenothera speciosa, meaning it spreads along the ground with short, well-branched, partly red stems. Its deciduous leaves are bright green, narrowly lanceolate, measuring 4–5 cm long and only about half a centimeter wide.
Its flowers are bright yellow, like the fresh peel of a ripe lemon, consisting of four elongated, heart-shaped petals with a shallowly notched tip. They open for only a few days, after which new ones bloom. These hybrid evening primroses are highly valued for their long flowering period, stretching from early June to September – how amazing is that?
They make an excellent summer ground cover and border plant alongside other drought-resistant perennials, such as verbena, sea holly, curry plant, or leadwort. The variety was bred by Silvia Hofmann in Gensingen, Germany, as a cross between hybrid varieties African Sun and Narrow Grey Leaved. It is protected by patents No. 20476 (EU – 2007) and PP16393 (USA – 2006).
How to grow hybrid sundrops with narrow leaves
🌱 Soil: Regular garden soil, well-draining, not too wet, pH value is not a concern.
💧 Watering: Once established, it handles dry periods well but avoid waterlogging.
🌞 Sunlight: Full sun is ideal for healthy growth.
🌿 Fertilization: From late May to late summer.
✂️ Maintenance: In spring, remove all above-ground parts.
❄️ Frost tolerance: Hardy down to −29 °C (USDA zone 5).
Evening primrose LEMON DROP is a fantastic choice for gardens seeking vivid colors and low-maintenance beauty. Once planted, it will reward you every summer with its lemon-yellow blossoms.
Last update 29-05-2025
