All about plant fertilization

How and when to fertilize wisteria


Wisteria or glycine is a climbing plant that produces beautiful clusters of flowers that open in early spring. Its color changes according to the variety, with lilac being the most common. In case of having a correct support they can climb up to 30 m in height, they are highly sought after to create corridors or floral tunnels. If you give them the necessary care (which is not much since it is very resistant) they can live 100 years. In this article we will discuss everything about fertilizer for wisteria.


To begin with, I want to clarify that the lack of flowering is not always solved with fertilizer. Other techniques like pruning are helpful, so if your wisteria isn’t blooming, don’t saturate it with fertilizers. Better to fall short on fertilizer than to overdo it. Remember, it is always easier to correct problems for lack of nutrients than for excess of them.

Fertilizer for wisteria
Important fact: we always like to indicate when a plant has poisonous components, so that you can take care of yourself. In the case of wisteria, all of its parts have a substance called wisterin, which is toxic. If ingested, it can present symptoms such as dizziness, nausea, vomiting, stomach pain, speech problems, among other symptoms.

1. How to care your wisteria


We have just mentioned that wisteria is a very resistant plant that needs little care, but even if there are few, it is good to know them. Now we will review them quickly and easily.

  • Sun: if you want to enjoy a good and abundant flowering you must place it in a place with very good sun exposure. In places with semi-shade it can develop perfectly, but it will always bloom more and better with many hours of sun a day.
  • Temprature: it perfectly resists some frosts, so if the winters are a bit strong where you live, don’t be afraid to plant it in your garden.
  • Soil: it is not too demanding on the soil. Although it is good if they are deep, since they have a very important root system. A requirement that cannot be lacking in the soil is that it have a good drainage capacity.
  • Irrigation: it is able to withstand long periods of drought. But just because you can handle them doesn’t mean it’s good for the plant. During spring and summer water to always keep the substrate with some moisture, do not wait until the soil is completely dry to water.
  • Pruning: a complete post would be necessary to explain this point in detail. Briefly, I can tell you that you should know that it blooms in shoots from the previous year. So if you prune it too much in winter, you will lose a lot of its bloom. One solution for this is to prune after flowering is complete.
  • Fertilization: there are wisteria that have not been fertilized throughout their life, and have grown and flowered correctly. Anyway, if you use the fertilizers correctly, they will give you an extra both in growth and in flowers, as we will see in the following sections.

2. Most important nutrients for wisteria


All plants need nutrients to live, and although not all need the same nutrients and the amounts are different, there are three nutrients that generally all plants must have. The case of glycine is no exception, we must provide the following three main nutrients

  • Nitrogen.
  • Phosphorus.
  • Potassium.

Throughout the life of glycine, the required doses of each of these nutrients change. For example, when he is young, what we need is for him to develop to fill the space that we have prepared for him. That is why at this stage it needs greater amounts of nitrogen (a fundamental nutrient for the generation of new stems and leaves).

Throughout the life of glycine, the required doses of each of these nutrients change

Later, when the plant is settled, what we will look for is a good flowering. That is why we do not want an excessive production of foliage but to get more and better flowers. This is where the need for other nutrients comes in, especially phosphorous. Its presence is essential for the production not only of flowers but also of roots, seeds and to improve resistance to diseases.

2.1 What NPK values are?

As we said, we can generally summarize the need for nutrients into the top three, nitrogen, phosphorus, and potassium. In case of buying a commercial fertilizer, it will be very useful to know what the NPK values ​​are. Since they indicate the concentration of these nutrients within the fertilizer.

NPK values ​​are presented in the format of three numbers separated by a dash (for example: 10-15-20). Specifically, what each of these numbers indicates is the percentage by weight of each nutrient over the total weight of the fertilizer.

So that you understand, let’s analyze an example. A 10 kg bag of 20-10-5 fertilizer counts within its compassion with 2 kg of nitrogen, 1 kg of phosphorus and 500 g of potassium. When all three numbers are equal (for example, 10-10-10) we have what we call a balanced fertilizer. Another very common case to see is a 46-0-0 nitrogen fertilizer, which is none other than the popular urea.

In the rest of this post on wisteria fertilization, I will name the fertilizers a couple of times by their NPK values. So I hope you have correctly understood what this simple concept is about. 😉

3. Best fertilizer for wisteria


There are many fertilizers that exist, but knowing what are the nutrients that a glycine needs, we can select the best ones. For this post to be better organized we will separate between organic and inorganic fertilizers.

As we will see below, using one or another type of fertilizer can bring its advantages and disadvantages. Therefore, from this blog we always recommend a mixed use of these fertilizers. In this way we will take advantage of the advantages of both and minimize their disadvantages.

[…] using one or another type of fertilizer can bring its advantages and disadvantages. Therefore, from this blog we always recommend a mixed use of these fertilizers.

For example, the main advantage of inorganics is that the nutrients are available for immediate use by plants. In addition, the exact amounts of any element can be calculated and said nutrient can be supplied to the plants in a quantified way. On the other hand, in chemical or inorganic fertilizers, their nutrients, especially nitrogen, easily “run off” under the roots, due to rain or irrigation. And an excessive dose can easily affect both your plant and the soil.

When using organic fertilizers, there is less danger of over-fertilization. In this case, the release of nutrients is slow, since it depends on the degradation of certain microorganisms in the soil. They will be responsible for transforming organic matter into inorganic compounds capable of being absorbed by plants. Slow release is usually an advantage, but this is not always the case. If we need immediate action, this ends up being a disadvantage. On the other hand, we cannot control the doses administered exactly, we do not know the exact proportions of nutrients in many of these fertilizers.

If you are reading this post, you will probably be interested in learning about fertilizing these other plants.

3.1 Inorganic fertilizer for glycine

Whenever we talk about an inorganic fertilizer, we will talk about its NPK values. In the case of wisteria and depending on the stage of its life in which it is, we will recommend two of these fertilizers:

  • 10-10-10: as we mentioned earlier, it is a balanced fertilizer. Able to provide in the same proportion amounts of nitrogen, potassium and phosphorus. It is very commonly used in all garden plants.
  • 0-20-0: What we have here is a phosphorus fertilizer, where we will only apply phosphorous to our plant. It is used above all in floral plants, seeking to improve the quantity and quality of flowering.

3.2 Organic fertilizer for wisteria

Among the organic fertilizers there are many that you can make at home, and others that are much easier to buy. You decide which one you want to use. 😉

  • Compost: When I recommend organic fertilizers for a plant, I can never ignore the compost. Wisteria, like any plant, can benefit a lot from compost since it is one of the most heterogeneous fertilizers that exist. Being able to provide all the nutrients, at the same time helping us to reuse almost all the organic matter that we produce at home.
  • Bone meal: this fertilizer is a very good source of phosphorus for wisteria. You can do it at home (putting animal bones to burn) or to make it easier to buy them in any nursery.
  • Worm humus: it is another very complete organic fertilizer, within its composition you will find nitrogen, potassium, phosphorus and many other micronutrients. It is a very good alternative to use as a replacement for traditional compost.
  • Chicken manure: It is a material with a good supply of nitrogen, in addition to phosphorus, potassium, calcium, magnesium, sulfur and some micronutrients. It generally contains about 4% N, 3% P, and 2% K.

There are many other organic fertilizers, continuing to name them would only extend the article. It is important that before applying an organic fertilizer you find out what its approximate composition is and knowing the needs of the glycine you will know if it is useful for it.

4. How and when to fertilize wisteria


How and when to fertilize a wisteria does not have a set rule, but depends on several factors, including the age of the plant and the properties of the soil. As this vine grows we will change our fertilization plan.

How and when to fertilize a wisteria does not have a set rule, but depends on several factors, including the age of the plant and the properties of the soil.

For this reason, we have divided this section into two parts. Analyzing the stage of youth and adulthood of wisteria.

4.1 Young wisteria

In youth what we want is for our wisteria to develop rapidly, until we can cover the space that we have given it. Whether we want to create a tunnel, cover a wall, make a vine or whatever. For this reason, it is at this stage that we will apply more nitrogen.

At each beginning of spring we will apply a balanced 10-10-10 fertilizer, preferably slow release. Therefore, it will release nutrients throughout the development stage. You can replace or supplement this fertilizer with an organic one like compost or worm castings. These will also provide a good source of nitrogen that will be available during spring and summer.

Once the wisteria has covered a good amount of surface and you notice that the flowering is quite abundant, you can consider that it has passed its youthful stage. Thus we have entered the adult age of this plant.

4.2 Adult wisteria

Once it reaches adulthood, we do not need it to continue growing in an accelerated way, but we will seek to improve its flowering. This, added to the fact that glycine has the ability to create its own nitrogen from the air, means that the amounts of this nutrient to apply should be almost nil at this stage.

We will only apply a nitrogen fertilizer when we notice that you need it. And you wonder, how do I know that my glycine needs nitrogen? Easy, you just have to be attentive to the coloring of its foliage. If you see that the leaves stop having a dark green color and turn light green or even slightly yellowish, it is because it is low in nitrogen. At that time apply a little nitrogen fertilizer to improve the coloration. Handle low doses, it is not good to exceed nitrogen.

As for flowering, what we will do is apply phosphorus fertilizers in early spring. For example, what you can do is buy a 0-20-0 fertilizer and apply it at a rate of about 2 ounces per square yard. This will give an impetus to improve the quantity and quality of the flowers. Again, you can replace or supplement this fertilizer with an organic one, such as bone meal.

If you want to better optimize your fertilization plan, it would be best to carry out a soil analysis annually or at least every two years. This will tell you what nutrients your wisteria has and which ones are missing. What you spend on this analysis can save you on fertilizers and help you avoid over-fertilizing.

5. Planting Wisteria video


In this blog we like videos, and since we are bloggers and not youtubers, what we do is select a video and in this case it is from the Garden Fever channel. Although it is not about the fertilization of wisteria plants, it will be good for you to see it, you will see how to plant this beautiful vine and take care of it so that it grows healthy and strong.

More information about wisteria plant:

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