Vincetoxicum nigrum, a species in the family Apocynaceae, also known as black swallow-wort, Louise's swallow-wort, or black dog-strangling vine, is a species of plant that is native to Europe and is found primarily in Italy, France, Portugal, and Spain. It is an invasive plant species in the northeastern United States, parts of the Midwest, southeastern Canada, and California. In 2020, wild plants were found in Timaru, New Zealand.
Black swallow-wort has strong resistance to disease and is usually not susceptible to illnesses. However, it can be affected by pests and diseases present in its environment. These infections are generally mild. Regarding care, the plant requires moderate upkeep. It should be trimmed regularly to preserve a neat appearance and support healthy growth. Fertilizing can also aid in encouraging blooms. Black swallow-wort is suitable for anyone with outdoor space, such as a garden or patio, and does not demand extensive plant-care experience. It may need more attention if grown indoors.
How to keep Cynanchum Louiseae.
Light
Black swallow-wort flourishes in settings with abundant sunlight throughout the day; however, it can adjust to situations where the exposure to sunlight isn't as continuous. Its evolutionary history in sunlight-rich areas allows it to survive changes in luminosity. If overexposed, it may wilt, and if underexposed, it might experience stunted growth.
Temperature
Black swallow-wort does well in temperate regions, preferring temperatures of 5 to 35 ℉ (-15 to 35 ℃). The plant can acclimate to temperature shifts by adjusting to seasonal patterns, for example being exposed to cooler conditions during winter dormancy.
Fertilizer
Typically, Black swallow-wort only needs one round of fertilizer application in the spring, yet multiple fertilization can bolster growth. It should be fed every one to one and a half months. Fertilization boosts the look and performance of its leaves, encouraging a uniform color and robust texture. Furthermore, it prompts the growth of roots and the absorption of nutrients, contributing to the sustained wellbeing of the plant.
Botanical profile.
- Plant Type
- Vine, Herb
- Life Cycle
- Perennial
- Genus
- Cynanchum
- Family
- Asclepiadaceae
- Hardiness Zone
- 4-9
- Mature Height
- 0.61 m to 1.83 m
- Mature Spread
- 91 cm
- Leaf Color
- Green
- Leaf Type
- Deciduous
- Flower Color
- Black
- Flower Size
- 0.51 cm to 0.76 cm
- Bloom Time
- Late spring, Early summer, Mid summer
- Planting Time
- Spring
- Harvest Time
- Mid summer
- Native Area
- France, Portugal, Spain, Italy
