Jacob's ladder plant is the commonly used name to describe the plants that make up the polemonium genus. About 30 species make up the genus, and they are found throughout North America, Asia, and Europe as well as parts of South America. It is a usually a perennial plant, with some annual varieties, and is very common in gardens around the world.
A Jacob's ladder plant will usually grow to about 12 inches (30 cm) in length, but variations that are both taller and shorter exist. The leaves of the plant are most often bright green and divide into smaller leaflets that are lace-like in appearance. Flowers bloom at the top of the stems in the late spring and early summer. Most often they bloom in June and last until the month of July. These flowers are usually purple or blue, but sometimes pink and white flowers are also seen. After blossoming both bees and other insects, such as moths, are attracted to it.
The Jacob's ladder plant is a popular garden plant in mild to temperate climates. It grows very easily, so much so that care must be given so it doesn't spread to unwanted areas of a person's garden. Unlike many other garden plants, the Jacob's ladder does not need direct sunlight in order to grow, and can thrive in the shade. It is also fairly hardy to drought, but it will usually dry up and die in very hot, sunny and dry climates. It is very resilient against cold though and can survive frigid conditions, as cold as -30 degrees Fahrenheit (-34 Celsius).
Most gardeners advise that Jacob's ladder plants be planted between 12 and 18 inches (30 to 45 cm) a part to promote growth and limit overcrowding. Many times gardeners will plant them as accompaniment to shrubs and larger garden plants. The soil it's planted in does not need to be exceptionally fertile; any moderately fertile soil should suit the plant fine. Clay soils or standing water will damage a Jacob's ladder plant and shorten its life however. A garden must have well-drained soil in order for the plant to survive.
Cats can often damage these plants. A Jacob's ladder plant emits a fragrance that has a catnip-like effect on the animals. It is harmless to the cats, but the domestic animals may damage or even destroy the plant if given the chance.