David’s Buddleia (Buddleja davidii) is a shrub of the family of Buddlejaceae who blooms profusely from the end of May until October. Its very fragrant long terminal inflorescences attract butterflies, hence its nickname of Butterfly Tree, and other pollinators. Very easy to grow, the Buddleia can quickly become invasive. Let’s take a look at the cultivation of this shrub native to China.
Planter un Buddleia
In the most southerly regions, which are particularly dry and where the heat persists, the Buddleia is preferably planted in fall, ideally between mid-September and the end of October. If the climatic conditions allow it, namely particularly mild temperatures and above all no frost, it can even be planted until the beginning of December in these regions. On the other hand, we choose the spring to plant the Butterfly Tree in a cold or very humid area, from the second half of March to the end of April.
The method of planting a Buddleia in the ground is the following.
- Dig a hole barely wider than the clod but very deep.
- Working the extracted earth to make it loose,
- Prepare a mixture composed of 50% of this garden soil and 50% of potting soil,
- Place a good layer of drainage at the bottom of the hole, such as one or two shovelfuls of gravel,
- Install the Buddleia in the center of the planting hole,
- Fill with the earth/potting mix,
- Tamp down,
- Water.
If you choose to plant several butterfly bushes to form a hedge flowering, take the precaution of separating them from each other by about 1 meter.
Here’s how to plant a Buddleia in pot.
- It is essential to choose a pot or a container fully drilledat least 65 cm deep and 50 cm wide,
- Place at the bottom of the container a layer of drainage composed for example of pozzolan, cocoa shells or even clay balls,
- Prepare a suitable substrate which can be composed of 40% garden soil and 60% leaf compost,
- Position the shrub in the center of the pot,
- Cover with the mixture,
- Pack around the foot,
- Water,
- Place the potted shrub in a sunny position and sheltered from the wind.
It is useful to lay a mulch at the foot of the Buddleia grown in a container in order to maintain the freshness of the substrate.
Once planting is complete, in the ground as well as in a containerit is recommended reduce twigs of the shrub about twenty centimeters. This slight pruning is intended to promote recovery.
Growing Buddleia or Butterfly Bush
The Buddleia likes to be installed in broad daylight, preferably sheltered from prevailing winds, for example along a wall. The heat is essential for it to flower in abundance. Ideally, it is grown in a poor, dry soil, well drained. But the Butterfly Bush is very tolerant since it proliferates perfectly in any type of soil. His only requirement is that the earth not become waterlogged. It is therefore necessary to guarantee this shrub a excellent drainage so that its roots do not rot.
Entertain a Buddleia
Perfect for people who don’t want to spend time gardening, the Buddleia doesn’t have big needs.
Water
It only needs very little watering in summer and you should know that the Buddleia shows itself more resistant still drought if the soil is deep. Only potted specimens need moderate watering once or twice a week during the summer. From autumn until the following spring, it is of course necessary to reduce watering.
Fertiliser
It is not necessary to add fertilizer if the Butterfly Bush is grown in the ground. It is also not recommended because too fertile soil promotes the development of the shrub to the detriment of flowers.
A small special mention, however, for the Buddleia in pot to which it is appropriate to distribute a handful or two oforganic fertilizer during the spring. Let’s not forget that in a tank, the substrate runs out. It is therefore essential to be able to replenish its reserves of nutrients once a year, when vegetation resumes.
Repot
Even in a pot, the Buddleia grows quickly. It is therefore advisable to repot it every year in the spring in order to install it in a container slightly larger than the previous one. We take the opportunity to offer him a new substrate.
Cut
David’s Buddleia is the species which tolerates particularly well the very severe sizes, but all varieties should benefit from a spring pruning, just before the resumption of vegetation. This pruning is unavoidable, if only to promote flowering, prevent the shrub from thinning out at the base and growing in an anarchic way, which would harm the elegance of its bearing.
But it is also essential because this ornamental shrub absolutely must be contained. It tends to multiply with great ease because of its adaptability. Note that only one specimen produced each year approximately three million seeds ! In this way, it does not take long to colonize ditches, embankments, walls and gardens. The Buddleia also grows in a paved driveway without any difficulty…
Finally, the maintenance of a Buddleia mainly consists of avoid over-scattering in order to preserve biodiversity because the Butterfly Tree is a real invader. To do this, it is recommended to carry out a severe pruning at the beginning of the year and in the spring to pull out the roots by hand of all the new unwanted plants.
We repeat the pruning as often as necessary to limit the vigor of the shrub and we systematically cut all the deflowered parts as we go to prevent seed formation. But care must then be taken to evacuate the residues in order to limit the dispersion of the Buddleia as much as possible.
Pests and diseases
Decidedly, the Buddleia is a easy-going ornamental shrub since it fears neither parasites nor diseases. It is just necessary to take care that its roots do not bathe in water because that promotes rotting.
Flowering of the Buddleia or Butterfly bush
Pour bloom profusely, the Buddleia absolutely needs to be in full sun. The panicled flowers appear at the top of the branches from the first summer after planting, and it is the woods of the year that flower. In winter, the flowers give way to clusters of brownish capsules which are none other than the fruits of the Butterfly Bush.
When buying a Buddleia, you can turn to a less fertile cultivar. There are indeed today horticultural varieties of buddleias that produce few seeds, which limits the risk of colonization.
These shrubs are all easy to grow and very decorative, their abundant flower spikes declining in a wide range of colors, pink, purple, white, mauve, blue… This allows you to admire a splendid monochrome. Namely that there is even a Buddleia with red flowers, Buddleia Royal red. Do not hesitate to create a free hedge made up of several varieties of buddleias of different tones, a solution which makes it possible to spread out the flowering periods. Finally, the dwarf varieties, which are also very pretty, are ideal for growing in pots, as is the case with Buddleia Nanho Blue.