Wisteria is a long-lived, twining vine famous for hanging spring flower clusters. Oregon State University Extension notes the vines can climb 30 to 40 feet, gain weight quickly and “can run aggressively” if left unpruned, so the main job is giving it a strong structure and pruning it every year.
Wisteria at a glance
| Type | Flower |
|---|---|
| Season | Perennial |
| Sun | Full sun |
| Plant spacing | 120 in |
| Row spacing | 120 in |
| Per square foot | 1 |
| Seed depth | At surface |
| Days to maturity | Flowers 3–4 years after planting |
| How to start | Plant a grafted or named wisteria in full sun between autumn and early spring, give it a very strong support and prune twice a year |
| Water | 1 in per week |
These are the same numbers our plant spacing, square foot and harvest date calculators use. See every crop in the plant database.
When to plant wisteria
The Royal Horticultural Society says October to April is the best planting window, and container plants can go in any time but establish more easily in autumn or winter. Most wisterias begin flowering within three to four years of planting; Oregon State says a young vine may take 2 to 3 years or longer. Seed-raised plants can take up to 20 years, so buy a grafted or named cultivar. Check your growing zone first.
How to plant wisteria
- Choose full sun and well-drained soil kept evenly moist but not wet. Slight shade is tolerated but reduces flowering (RHS).
- Build a very strong support first: a pergola, arch or wall wires. Do not train it onto gutters, roofs or weak trellis.
- Containers need to be at least 18 inches deep (RHS).
Caring for wisteria
Prune twice a year. In winter, cut excess growth back to the trunk and shorten remaining runners to 2 or 3 buds (about 6 inches). In summer, remove excess growth and clip back to 2 or 3 buds (Oregon State). The RHS gives July–August for cutting whippy growth to five or six leaves, then February for shortening to two or three buds. Leave young plants unpruned until they have covered their structure.
Water well when newly planted and in dry spells; a water shortage from July to September can affect bud formation (RHS). Fertilize lightly with a low-nitrogen product once a year, every other year or not at all. See the garden watering calculator.
Companion plants
| Grow nearby | Plant on its own with a sturdy pergola, arch or wall |
|---|---|
| Keep apart | Gutters, roofs, small trees and light trellis it can overwhelm |
Sources do not give companion plants; the priority is a strong support and room to prune. Check other pairings with the companion plant finder.
Common problems
| Problem | What you see | What to do |
|---|---|---|
| No flowers | Healthy leaves but no blooms | Common causes: seed-raised or very young plant, too much nitrogen, deep shade, pruning at the wrong time, summer drought, spring frost on buds, or potassium-poor soil. Oregon State suggests light root pruning with a shovel 1–2 feet from the trunk. |
| Overgrown vine | Shoots in gutters, roofs or trees | Not pruning is called the most common mistake by Oregon State. Prune twice yearly to 2–3 buds. |
| Powdery mildew or scale | Brown blotches on leaves or scale insects | Listed by the RHS among possible pests and diseases; see the pest identifier. |
Not sure what you are looking at? The plant problem identifier ranks likely causes from the symptoms you see.
When and how to harvest
Wisteria is grown for its flowers, not for harvest. Oregon State warns that the seeds and fuzzy seed pods are toxic, so keep them away from children and pets; see our pet-safe plants guide.
Plan your wisteria
- Plant spacing calculator: how many plants fit your bed
- Planting calendar: sowing and transplant dates for your frost dates
- Frost dates by ZIP code: your last spring and first fall frost
- Harvest date calculator: when your crop will be ready
Frequently asked questions
How far apart should I plant wisterias?
Space wisterias 120 inches apart in rows 120 inches apart. In a square foot garden, plant 1 per square foot.
How deep do I plant wisteria plant?
Plant at the same depth it grew in its container; use a container at least 18 inches deep if growing in a pot.
How long do wisterias take to grow?
Most wisterias flower within 3–4 years of planting; Oregon State says 2–3 years or longer for a young vine.
How much water do wisterias need?
About 1 inch of water a week, from rain and watering combined. Water well when new and in dry spells; keep soil evenly moist, not wet.
When should I prune wisteria?
Twice a year, in summer and winter, cutting back to 2 or 3 buds.
Why won’t my wisteria bloom?
Likely too young, seed-raised, too much nitrogen, too much shade, mis-timed pruning or frost-damaged buds.
Are wisteria seeds poisonous?
Yes. Oregon State says the seeds and fuzzy pods are toxic.