Wisteria grows quickly, adding 90 cm (3 feet) or more in height each year. Wisteria sometimes become invasive when planted in a garden bed, but growing the vines in a pot helps contain the growth. Regular pruning and proper care practices keep the wisteria vine manageable. When provided with the necessary cultural needs, the wisteria plant produces an abundance of pendulous, lavender blossoms in early summer.
Place a half-barrel or similar sized planter in its permanent location before filling it with soil, since it will be too heavy to move afterward. Select a location that receives full sunlight, but offers protection from high winds.
Fill the half-barrel planter with potting soil formulated for roses, azaleas or other acid-loving plants. Wisteria have the same acidic soil requirements as these flowering plants.
Mix an azalea fertiliser with the soil at the label-recommended rate if the soil doesn't come pre-fertilised. Azalea fertilisers are formulated to provide the necessary nutrients for wisteria and other acid-loving plants. Don't use general-purpose fertiliser blends, as they result only in foliage with minimal flowers.
Lift the wisteria vine out of its nursery container. Plant it inside the half-barrel so it is at the same depth it was growing previously. The top of the soil should sit 7.5 cm (3 inches) beneath the rim of the barrel.
Insert a tall espalier or container trellis into the barrel behind the wisteria vine. Push the stake for the espalier into the soil until it touches the bottom of the barrel.
Water the soil when the top 5 to 7.5 cm (2 to 3 inches) feel dry. Container-grown wisteria need watering every three to five days in summer so the soil doesn't dry out completely.
Prune the wisteria at any time during the spring and summer growing season. Cut out damaged vines and those that become overgrown or too tall. A wisteria tolerates severe pruning, and several trims are necessary each summer to keep it small enough for the container.
A wisteria plant rarely requires fertilisation, but if the foliage becomes weak or yellow, a light application of azalea fertiliser in spring may help return it to its former health.
Wisteria vines that receive too little sun, too much fertiliser, or too much water will not produce flowers at their full potential.