What Is The Best Fertilizer For Wisteria

Wisteria normally grows without much difficulty. This strong vine doesn’t need extremely fertile soil to achieve a huge size soon. However, there are several circumstances where fertilizer will aid in the growth of wisteria.

fertilizer is required for wisteria if

Since the plant is young, you want to promote rapid growth.
Even though it has had time to grow roots and receives enough of sunlight, it isn’t blossoming.
It is being grown in a container.
You got your soil analyzed and found a nutritional shortage as to why it isn’t flourishing.

Using the appropriate fertilizer is crucial in each circumstance. Wisteria is a nitrogen-fixing plant, just like other members of the pea family. You typically don’t need to add nitrogen to the soil of your wisteria because it obtains nitrogen from the air rather than the soil. If your plants receive too much nitrogen, they may start to produce more leaves and stems than blossoms.

If plants consume an excessive amount of nutrients or if substances that are only safe for plants in tiny quantities build up in the soil, too much fertilizer can also be harmful to the plants. It would probably be wise to save time and money by forgoing fertilizer if your soil is already productive.

We’ll go over each of the situations we described below and offer our recommendations for how to fertilize your particular Wisteria.

Helping Young Wisteria Grow Faster

Wisteria is typically trained over the first few years after planting to grow over a trellis, fence, wall, or other structure, or even into a tree shape. During this time, you should establish the wisteria and, if it was planted to cover a building, encourage rapid growth. Fertilizer can be useful in this case.

Wisteria typically doesn’t require nitrogen fertilizer, but since nitrogen promotes plant development and foliage, adding a little extra can hasten growth. During the first two or three years after you plant it, an all-purpose fertilizer with an NPK ratio of 10, 10, 10 is a suitable choice. (Assuming you purchased the plant from a nursery. It will take much longer for wisteria grown from seeds to attain maturity.)

Use of nitrogen fertilizer should end once the wisteria has grown to around the desired size and/or has begun to bloom. Fertilizer is frequently of no use to mature Wisteria, and too much nitrogen can prevent it from blooming.

Read on for our recommendations on how and when to apply fertilizer, or move on to our special advise on fertilizers for young Wisteria.

Getting Wisteria to Bloom

Inability to get Wisteria to blossom is one of the most frequent issues gardeners encounter, and fertilizer can occasionally help. Many popular garden plants, like Wisteria, are encouraged to blossom by the use of phosphorus and potassium fertilizers.

The following fertilizers work best to promote flowering in wisteria:

fertilizer for flowers
Fertilizers with phosphorus and potassium, like potassium sulfate and superphosphate

If you are having difficulties getting your wisteria to blossom, make sure you are not using nitrogen fertilizer as nitrogen encourages foliage growth at the expense of flowers. Additionally, it’s a good idea to keep Wisteria away from other plants that require nitrogen fertilizer. Sometimes Wisteria doesn’t flower because of fertilizer run-off from lawns.

But it’s crucial to keep in mind that if anything else isn’t right, fertilizer won’t be able to make Wisteria blossom. Wisteria requires a lot of sunshine to bloom, and occasionally buds are lost due to cold temperatures or improper trimming. Fertilizer won’t help under those circumstances. Sometimes wisteria just needs some time to grow its roots before it may begin to bloom.

Want to learn more about typical problems that lead to barren wisteria? The top 7 explanations for why your wisteria might not be blooming are covered in a different article on our website. Or scroll down to see our suggestions for wisteria fertilizers.

Growing Wisteria in Containers

In containers grown wisteria plants, regular feeding is required. You should add minerals to potting soil at least once a year because it depletes far more quickly than soil in your yard or garden.

Growing Wisteria in Poor Soil

Wisteria does require some nutrients from the soil, though not many. If you have a nutrient shortage or are aware that your soil is low quality, you should fertilize your plants accordingly. The nutrients your soil is lacking and how much you need to add can be determined via soil tests.

Of fact, even if a test indicates that your soil is deficient in nutrients, if your Wisteria is flourishing, it usually doesn’t need fertilizer. One of the plants that can occasionally thrive in poor soil is wisteria.

What can I use to feed the wisteria?

Wisterias thrive in full light, fertile soil, and both. Of the 10 species, three are grown the most frequently: Wisteria brachybotrys, Wisteria sinensis, and Wisteria floribunda, which are native to China, Japan, and the eastern United States (silky wisteria). All three species have significant growth rates and can extend out to a maximum of 20 meters (66 feet) against a wall or around 10 meters (33 feet) in trees. Wisteria can also be trained to grow as a free-standing standard in a big container or border.

Wisterias for pergolas and arches

The Japanese wisteria (Wisteria floribunda) is best exhibited hanging down from a garden structure like a pergola or arch since it has the longest flower sprays (or racemes) of all the species. They entwine in a clockwise motion while simultaneously bearing blooms and leaves. Lilac blue blooms and racemes as long as 1.2 meters (4 feet) are produced by Wisteria floribunda f. multijuga AGM in the early summer.

Wisterias for walls

Wisteria sinensis, often known as Chinese wisteria, blooms in the springtime before the leaves do. For example, Wisteria sinensis ‘Amethyst’ AGM has violet blue blooms with a reddish flush produced in dense racemes to 30cm (1ft) long in late spring or early summer. They twine anticlockwise and the racemes are shorter so they are best presented against a wall.

Silky wisteria (Wisteria brachybotrys), which can be grown against walls or on pergolas, with downy leaves and small racemes of 10-15cm (4-6in). White flowers with center yellow markings, a strong perfume, and 10-15 cm tall sprays of wisteria brachybotrys f. albiflora ‘Shiro-kapitan’ AGM bloom in the spring and early summer.

If you want to cultivate a wisteria in a big container

It is best to choose Wisteria fructens ‘Amethyst Falls’ because of its compact habit and rich clusters of lilac-blue blooms.

Always choose a wisteria that has been developed from cuttings or by grafting when purchasing one because seed-raised wisterias flower less consistently and take longer to bloom. The graft union should be seen as a swelling close to the stem’s base. Unlike species, named cultivars are virtually always grafted. Purchase your wisteria in flower or go with a specific cultivar to avoid disappointment.

Wisterias are offered for sale as container-grown plants at garden centers and online, and you can use the RHS Find a Plant tool to locate particular cultivars.

Wisteria should ideally be planted between October and April. Wisterias grown in containers can be planted at any time of the year, but fall and winter are the easiest times to maintain. Give them healthy, well-drained soil to plant in.

Wisterias bloom best in full sun, so pick a wall or pergola that faces south or west. Although blossoming will be diminished, they will still grow in light shade.

Wisterias are robust climbers that can grow to a height and width of more than 10 meters (33 feet). You’ll need to give support in the form of wires, trellises, or outside buildings like pergolas or arches against a wall. Wisteria can also be grown up a support or taught up a tree to create a standard. A wisteria can be grown in a border or container by being trained into a standard, which reduces its vigor.

If you want to grow your wisteria in a container, you’ll need a sizable one that is at least 45 cm (18 in) in diameter and is filled with potting soil with a loam basis, like John Innes No. 3.

Feeding

Use Growmore or Fish, Blood and Bone on your wisteria in the spring at the suggested rate listed on the packet. Additionally, apply sulphate of potash at a rate of 20g per sq m (1/2 oz per sq yard) on sandy soils (which have low potassium levels). Fertilizers for flowering shrubs or roses are another option.

Feed wisteria in containers using Miracle-Gro, Phostrogen, or another comparable flowering plant food. A different option is to add controlled-release fertilizer to the compost.

Although wisteria has a reputation for being challenging to prune, this is untrue. Once you’ve made it a habit to prune your wisteria twice a year, you should be rewarded with a pleasing flower show.

When you prune regularly, you reduce the excessive, whippy growth from July and August to five to six leaves, or roughly 30 cm (1ft). This increases the possibility of blossom buds budding and permits the wood to ripen. Then, in February, trim these shoots even more to two or three buds, or around 10 cm (4 in), to tidy up the plant before the growing season starts and make it possible to observe the new flowers.

When your juvenile wisteria has completely covered a wall or other garden structure, start the routine pruning to promote flowering.

Small gardens benefit greatly from the training of wisteria as a free-standing standard in a border or container.

Wisteria can be trained to ascend into a tiny tree’s canopy, however doing so could eventually harm the tree. Pruning will be challenging if the plant develops into a huge tree, and a dense leaf canopy will affect flowering.

Increase your wisteria stocks by layering in the summer, taking softwood cuttings in the spring to mid-summer, or taking hardwood cuttings in the winter since seed-raised wisteria can take up to 20 years to flower.

Wisteria is typically propagated via grafting in professional nurseries, however layering is the simplest and most dependable technique for home gardeners.

Established wisteria can produce hanging, bean-like seedpods after a lengthy summer. While wisteria plants grown from seeds are typically of inferior quality, you might want to try growing wisteria yourself.

After the leaves have fallen, gather the seedpods and let them ripen in an open tray.
When the seed is ready, twist open the pod and sow it 2 cm (3/4 in) deep in seed compost.
Before planting if the seed is dry, soak it for 24 hours.

See our commonly asked questions page for a summary of wisteria issues.

Poor flowering

Poor flowering is the most frequent issue for backyard gardeners, and it can be brought on by a variety of factors, such as:

Young plants can take up to 20 years to flower, so acquire a plant that is already in bloom or go with a certain cultivar because they are typically grafted to avoid disappointment.
Examine your pruning methods and timing because early and midsummer trimming will prevent the growth of flowers the next year.
Wisteria flowers best in broad light; deep shadow produces few, if any, flowers.
Water your wisteria during periods of drought from July to September because a lack of water during this time will influence the development of flower buds the next year.
Flower buds may drop before opening as a result of spring frosts, which can harm or deform growing flowers.
Applying sulphate of potash in the spring will encourage bloom production for the next year in soils that may lack potassium.
The damage caused by pigeons or mice can be identified by torn petals or distinctive teeth marks.

Is wisteria compatible with epsom salt?

A 15-foot branch of my 5-year-old, robust wisteria has grown on a big pine tree. It’s never had a bloom. Is it required to plant another wisteria vine for pollination? Kingwood, CP

You don’t need another wisteria, to be honest. This vine can bloom quite slowly, which puts a gardener’s patience to the test. Even grafted plants can take several years to blossom compared to seed-grown varieties. Don’t use high-nitrogen fertilizer because it will promote vegetative growth instead of blooming. Avoid pruning in the winter to prevent removing fall buds that will blossom in the spring. To regulate their size after they flower (or should have flowered) in the spring, wisterias should be heavily pruned. Tip-prune later in the growing season to promote branches and shorten streamers.

Sunlight is ideal for wisteria flowers. To promote flowering, fertilize with phosphorus in the fall, but don’t overdo it—phosphorus buildup in our soils is typical. Plants are unable to absorb phosphorus when it is bound up in the soil. By offering magnesium and releasing nutrients required for blooming, epsom salt can be helpful.

In order to shock plants and potentially induce bud set, root-prune your vines in the early fall if they are still reluctant to blossom. Drive a pointed spade about a foot down, all the way around, about two feet from the vine’s trunk.

Many gardeners advise smacking the trunk to promote flowers. Visit the “beating plants” blog post by the Lazy Gardener.

Is wisteria tolerant to bone meal?

In the spring, wisteria blooms ferociously, producing clusters of lilac-colored flowers on fresh growth that develops from spurs off the main stalks. Check out our Wisteria Growing Guide for more information on wisteria maintenance, including planting and pruning.

About Wisteria

Wisteria is a long-living vining shrub with cascades of blue to purple blossoms that, in the spring and early summer, look stunning hanging from a pergola or archway. However, this vine is known to grow fairly heavy and to grow quickly and aggressively, frequently reaching lengths of more than 30 feet. It’s advised not to put wisteria vines too close to your home since they will squirm their way into any crack or crevice they can find.

Beautifully fragrant wisteria flowers offer a feast for the senses. A brown, bean-like pod remains on the plant during the winter after flowering. There are only blooms on fresh growth.

Note: Be careful when planting wisteria! The wisteria plant contains lectin and wisterin, which are poisonous to people, animals, and even pets. If taken in significant quantities, these poisons can result in anything from nausea and diarrhea to death.

Is Wisteria an Invasive Plant?

The wisteria species Wisteria sinensis and Wisteria floribunda, which are not native to North America, are regarded as invasive in several areas. If you want to add a new wisteria to your garden, we advise choosing one of the native North American varieties, such as American wisteria (Wisteria frutescens) or Kentucky wisteria (Wisteria macrostachya), which are excellent alternatives to the Asian species.

Do you want to know how to distinguish between North American and Asian species?

While North American wisteria is not quite as aggressive in its growing tendencies and has smooth seed pods and fruits in addition to more-or-less cylindrical, bean-shaped seeds, Asian wisteria is an aggressive grower with fuzzy seed pods. Another distinction is that the flowers of American and Kentucky wisterias appear in the late spring after the plant has begun to leaf out, whereas those of Chinese wisteria do not.

When to Plant Wisteria

Plant during the plant’s dormant season in the spring or fall.
Wisteria can be grown from seed, although plants from seeds frequently take many years to mature and begin to bloom. It is advised to buy wisteria plants that are already established or to begin with a cutting.

Where to Plant Wisteria

Put a plant in full sun. Even while wisteria will grow in some shade, it won’t likely bloom. Sunlight is necessary.
Wisteria should be grown in fertile, wet, but well-draining soil.
Wisteria will grow in most soils unless it is in bad condition, in which case you need add compost. Find out more about soil improvements and getting the soil ready for planting.
Because wisteria grows swiftly and can easily engulf its neighbors, pick a location apart from other plants.
Additionally, wisteria is renowned for encroaching on and infiltrating surrounding buildings like homes, garages, sheds, and so on. We highly advise against growing wisteria too near your house!
Wisteria vines need a very strong support, like a metal or wooden trellis or pergola, to climb on. Plan carefully and use substantial materials to construct your structure because mature plants have been known to become so heavy that they destroy their supports.

Wisteria looks gorgeous growing up the side of a house, but use caution when planting it because it is a very strong vine that will get into any crack or gap!

Caring for Wisteria

Apply a 2-inch layer of mulch and a layer of compost under the plant each spring to keep moisture in and keep weeds at bay.
Phosphorus is often used by gardeners to promote flowering. In the spring, work a few cups of bone meal into the soil. Then, in the fall, add some rock phosphate. Study up on soil amendments.
If you get less than an inch of rain each week, water your plants. (To determine how much rain you are receiving, set an empty food can outside and use a measuring stick to gauge the depth of the water.)
During the summer, try pruning the out-of-control shoots every two weeks for more blooms.

Pruning Wisteria

In the late winter, prune wisteria. Remove at least half of the growth from the previous year, leaving only a few buds on each stem.
Also prune in the summer after customary flowering if you prefer a more formal appearance. On fresh growth, spurs from the main shoots of the wisteria develop its blossoms. Trim back every new shoot from this year to a spur, leaving no more than 6 inches of growth. So that there are no free, trailing shoots, the entire plant can be trained, roped in, and otherwise organized throughout this procedure.
Mature plants that have been cultivated informally require little to no more pruning. However, for a plant that has been formally trained, side branches should be pruned back in the summer to 6 inches, then again in the winter to 3 buds.
Possess you a fresh wisteria? After planting, aggressively prune the vine. Then, the next year, trim the main stem or stems to a height of 3 feet from the growth of the previous year. After the framework has grown to its full size, midsummer extension growth should be cut back to where it started that season.