Once the winter has passed, us gardening fanatics breathe a sigh of relief and wait longingly for springtime to burst into bud. One of the most beloved flowers unfurls as the world warms, sharing lustrous fragrance and beauty as it does. Yes, I’m talking about the gorgeous wisteria vine. It’s cherished around the world, and I’m going to teach you how to cultivate and care for yours.
Springtime is my favorite season, as I’m sure it is for thousands of other gardeners all around the globe. For myself, the new growing season brings joy and expectation with it. Infant buds begin to appear throughout the garden, and before we know it, summer is upon us. This is when we celebrate the deliciously scented flowers boasted by the most sought-after plant to reach our shores.
The woody-stemmed, twining wisteria vine is one of the most adored garden treasures of our time. Just the sight of it in full bloom can sum up an image of the ideal quintessential English Country Garden. No matter where in the world you live, this vine’s long, draping racemes of scented pea-like flowers bring a touch of old-fashioned romance and drama to any garden setting. It embodies the bygone era of afternoon tea and balmy evenings. Oh, bring it back!
Wisteria Vine Varieties
This plant belongs to the Legume family native to China, Korea and Japan. It contains Chinese Wisteria (Wisteris sinensi), Japanese Wisteria (Wisteria floribunda), and the U.S. variety—Wisteria frutescens. Each of these versions is known as fully hardy, although all of the W. sinensis varieties, tend to be slightly more picky about where they are situated, and dislike very cold weather.
Wisteria sinensis was brought into the United States for horticultural use in around 1816. The Japanese version was introduced in around 1830. All these years later, there are many different varieties, with cultivars producing white, pink, violet, blue, mauve and purple flowers. Some blooms are single, some double and some dual colored. Let’s explore their beautiful differences in all their glory!
Wisteria Sinensis Cultivar
The W. sinensis is known as one of the post popular cultivars for home garden use, and is hardy in zones 5 – 9. These can tolerate any soil, but will produce far greater flowers in a sheltered, sunny setting with moist, well-drained soil. As with all wisterias, these are most suitable for training up against a wall or fence. They also look gorgeous draped over a pergola, and even through tree branches.
It’s also possible to grow them as a “standardised” plant. Make sure they’re pruned regularly and have enough support for their heavy, vigorous growth. In this form, they’ll grow compactly to around 5 feet, but pruning is a must or it’ll just look a mess. Here are my favorite two from this cultivar:
- Wisteria sinensis “Prolific” – A deciduous climbing vine with a mass of strongly scented, classic purple flower racemes growing to over 12 inches in length. This is one of the earlier blooming varieties, which will start flowering in late spring. Prefers a sunny position.
- Wisteria sinensis “Alba” – Quite a vigorous grower with slightly smaller flowers than the “Prolific”. The deep-green leaves are copper-tinged in their youth. They’ll grow to 12 inches long, each divided into oval leaflets. The sumptuous, sweetly scented, pure white blooms start from late spring. This vine can grow up to 30 meters long.
Wisteria floribunda Cultivar
One of the most prolific flowering cultivars of the Wisteria family. There are many varieties to choose from, but here are my favorite two:
- Wisteria floribunda “Multijuga” – A true gem: this has long, sweet-scented, pendulous flower raceme clusters that can grow in excess of 35 inches. Their blooms are a very attractive two-tone of light lilac and dark violet, which start to flower in late spring. The flowers tend to develop at the same rate as the pale green, pointed oval leaflets. At maturity, it can grow to 28 feet, or 9 meters long. Suitable for growing in a sheltered site in zones 5-9.
- Wisteria floribunda “Alba” – A pure white version with slightly smaller scented blooms. The flowers grow 24 around inches long and start to flower in late Spring. Mid-green, pointed leaflets and a mature size of 28 feet. Also suitable for growing in a sheltered site in zones 5-9.
- Also check out the W. floribunda “Rosea”, which has super rose-pink flowers.
Wisteria frutescens cultivar
This is a distinctive variety found in the southeastern United States, commonly growing in wet forests and on riverbanks. It’s not really used so much as an ornamental plant as alternative varieties. That said, it has similar, though much smaller blue-purple flower 7-inch-long racemes, and a less vigorous growing habit.
Although this is an unscented variety, it’s seen as a much more manageable specimen by bonsai enthusiasts. They prefer the smaller flowers and shiny dark green leaves. I would definitely recommend the Asian varieties for garden planting, as the scent is part of the pleasure.
Planting Your Wisteria Vine
There are two incredibly important aspects to consider when planting: the soil, and the site.
First, choose your site carefully. A fully grown vine is very heavy and will need suitable support. Choose a structure to hold it up, or trellis-work to tie it to, against a wall or fence. It’s best to pick a sunny and sheltered site, as wisteria vines don’t like harsh winds and inclement weather. Their flowers are long-awaited, so pick a site that will give them some protection.
The best soil for any planting is one that’s well-drained. Once you’ve picked your site, dig a large hole (at least twice the size of your pot), and incorporate some soil conditioners into it. This can be in the form of well-rotted compost or even some better quality topsoil, should you need it.
Plant your vine so that the top of the soil is at the same level as the top of the root-ball. Refill your planting hole with the conditioned soil and use your boot heel to tamp it down. This ensures proper connection is made between the roots and the soil. Once this has been done, stake the new planting to protect it from the wind, and water it thoroughly.
Caring for Your Wisteria Vine
Watering Requirements
Don’t let your wisteria vine dry out completely, especially in infancy when it’s vulnerable. Give the vine a good soaking at least once a week throughout the growing season—more if the weather is really dry and hot.Throughout the winter months, the plant will lose its leaves and go into dormancy until the following spring. Less water is needed in this time, and to be honest, the winter weather will usually do this job for you.
Feeding Your Wisteria
Your mature wisteria vine will benefit from a feed that contains potassium and phosphate. They don’t generally like to have too much nitrogen in the feed, as this element can stop your vine from flowering. Check your local garden center for a suitable liquid fertilizer.
Pruning Your Wisteria Vine: A must for Good Form and Prolific Flowering
When it comes to pruning, many people scratch their heads, unsure of what to prune and when. In the case of wisteria, the growth tends to happen really quickly, which can make the job twice as confusing. Hopefully, by following the simple rules below, it should all become a little clearer.
Flowers always develop in buds located at the base of the previous years’ growth. Prune back all of the side shoots in early springtime to the basal three buds.
Once flowered, prune all side shoots in the summertime to around 20 cm. Repeat this again in the autumn. This won’t just control the size of your vine, it will help to produce the best flowers possible.
After the vine is a few years old, it’ll be a compact, productive specimen. Continue to prune off the new tendrils 2 to 3 times per year every the growing season.
Providing Structure for a Heavy Plant
As mentioned earlier, every wisteria vine is vigorous and twining. This is why they’re typically grown up against a wall or fence, or over a garden structure. Once fully grown and in full flowering beauty, these woody vines are very heavy. They need a strong, suitable structure to support their weight.
Training against a wall or Fence
Wisteria wines are perfect for training up against walls and fences. These are naturally strong constructions, and when in the right spot, will provide necessary shelter from winds and inclement weather. You can train your young vine into a fan-shape remarkably easily, using garden wire and staple pins. It’s far easier to start this earlier when the vine is more pliable.
Growing Problems and How to Sort Them Out
Pests and Diseases
Fungal leaf diseases such as powdery mildew and leaf spot are fairly common in wisteria. Avoided these by ensuring they’ve been pruned adequately, (which will increase air flow around the plant), and spraying with a horticultural oil (such as Neem), once the affected leaves have been plucked off.
There’s a nasty beetle called the Wisteria Borer, which can cause problems inside your vine. These tiny insects munch round holes in the woody stems and lay their eggs within the plant. Unfortunately, there’s not a great deal you can do about them once they are in, apart from removing the vine and replacing it. However, by keeping your plant healthy, well watered and fed, this nasty critter will look elsewhere. These beetles only like stressed-out plants.
Die-back
In some circumstances, plant die-back can be caused by very cold bouts of weather. Ensure that your wisteria is sited in a suitable place from the start, and that the plant you choose is already a healthy specimen.
Damaged Flower Buds
Late frosts can sometimes damage developing flowers. This generally only happens if there has been a very warm, early spring and then a very cold spell. Correct siting of your plant should avoid this problem, but unfortunately we have no control over Mother Nature.
Failure to Bloom
All wisteria varieties have to reach full maturity before they’ll start to flower. This can take many years, and is a constant source of frustration for impatient gardeners everywhere—myself included.
But fear not: all good things come to those who wait!