There are three main types (two Asian and one American). They often look so similar that it’s difficult to distinguish between them, but one identifying feature is the pods. Those of Asian type are covered in fuzz; those of the American type are smooth. While the Asian wisterias are similar in appearance to the American, there are important differences to consider before deciding which type to grow.
Light
Wisteria performs best in full sun when grown in the North. In the South, down in zone 8, however, it profits from afternoon shade.
Soil
The most important soil requirement for growing wisteria is good drainage.
Water
Wisteria has average water needs.
Temperature and Humidity
Wisteria on occasion is successfully grown in zone 9, but further south than that, the climate is too hot and humid to grow wisteria.
Fertilizer
Use fertilizer high in phosphorus (the P in the NPK). Because wisterias belong to a plant family known for its nitrogen-fixing ability, don’t fertilize them with nitrogen. They have enough already. Early spring is the best time to fertilize.
Types of Wisteria
Wisteria commonly comes in three species:
Chinese wisteria (Wisteria sinensis), which can live up to 100 yearsJapanese wisteria (Wisteria floribunda), which arrived in the U.S. from Japan in the early 19th centuryAmerican wisteria (Wisteria frutescens), the smallest species, growing only two-thirds as long as the Asian types
You’ll have more trouble getting either of the Asian types to bloom in North America, so American wisteria is the best choice for North American gardeners.
Pruning
As with any plant, prune off dead, damaged, or diseased growth whenever you spot it. Asian wisterias need regular pruning to keep their shape. Since they’re vigorous and spread through runners, you must prune yearly to restrict their growth. The less vigorous American wisteria requires less pruning. Prune wisteria yearly in two stages:
Propagating Wisteria
To propagate, choose a green, non-woody stem in late spring or early summer and cut right below a node (sterilize pruners first with alcohol). A cutting should have two sets of leaves and a node; it should be four inches long. Once you have the cutting:
How to Grow Wisteria From Seed
To grow wisteria from seed, the temperature has to be about 65 degrees Fahrenheir or warmer. To propagate via seed in spring:
Overwintering
Wisteria is a hardy plant, as long as you don’t live north of zone 5. No special steps are required to winterize it.
Common Problems for Wisteria
Because it’s toxic, wisteria is deer-resistant. It also tends not to be bothered by insects. However, there is a common problem wisteria owners may face:
Failure to Flower
The failure of an Asian wisteria to flower is sometimes due to excess nitrogen. Since wisteria is a nitrogen-fixer, adding more nitrogen to the soil through fertilizing can lead to such excess nitrogen. Nitrogen can cause energy to go into the production of leaves at the expense of flowers. If excess nitrogen isn’t the issue, there are steps to take to solve the problem:
