Dipladénia or Mandevilla (Mandevilla spp.), also called Brazilian jasmine, is a climbing plant of the family of Apocynaceae much appreciated for profusion of its beautiful flowers funnel-shaped which come in white, red, pink… Fairly easy to grow, the Dipladénia is however demanding in terms of light and sunshine to flower profusely. It must also be watered very regularly and fed with a fertilizer for geranium from May until the end of August, twice a month. In addition, we think of overwintering it because it is not hardy. An unheated veranda suits him perfectly. Where things get tricky for inexperienced gardeners is when prune Dipladenia. Here are the tips to follow to avoid making mistakes that could jeopardize its flowering.
When to prune a Dipladenia?
This is at the end of winter that annual pruning dipladénias is essential, even before taking out the pots that we have taken care to winter, namely in February or early March, the resumption of vegetation being imminent. At this time, we can see that many stems from the past year have withered, some are even completely dry, and the plant also has multiple dead leaves. It should therefore be restored, but not in any way.
Enter here mid-June and the beginning of september A training size can be carried out as soon as necessary in order to discipline stems that have grown out of control. This size is not mandatory.
The autumn pruning is recommended if the plant has developed a lot. It takes place before the first frost, when the Dipladénia must be wintered.
Whatever the time, any section of rod can be immediately put in the water. Once roots have formed, simply plant this cutting in potting soil.
How to prune a Dipladenia?
This is done differently depending on whether you are pruning in the spring, a training pruning or the pruning that precedes wintering.
Annual late winter pruning
It stimulates growth. We cannot therefore deviate from it.
It is possible to be satisfied with a light size to encourage the plant to branch. Of course, before slaughtering this climber by pruning it randomly, it should be noted that it blooms on the shoots of the year. Hence the interest of doing it early enough because if you remove new branches, it will not produce flowers at all. It would be a shame, given the spectacular effect of a Dipladénia in full bloom on the terrace, the balcony or in the ornamental garden.
So we start with examiner the Mandevilla in order toidentifier the stems that should not be touched and those that must be pruned. It is essential to keep your frame, consisting of the largest branches. They are also identified by their color, a more or less dark brown and marked with grayish streaks. Death carpenter branches depart from numerous ramifications on which the buds develop. It is only these shoots that should be pruned, making a clean cut above a bud. This will help to promote new ramifications, these young shoots producing flowers. At the same time, all the dead stems are removed.
Note that pruning at the end of winter is limited to the shortening of the secondary stems when one does not wish to modify the size of the Dipladenia. No need in this case to intervene on the main stem. On the other hand, insofar as we want to reduce its size, then it is essential to cut the main stem and certain secondary stems entirely to 50% of its length.
Severe pruning of Dipladenia
Severe pruning is justified on very old topics with a lanky frame that will find a new youth. You can fold the main stems down so as to shorten them by 70%, or even more, but be careful to keep at least two eyes on each of them. This type of pruning is also essential for dipladenias that have undergone big damage due to a frost episode. In these two situations, therefore, there is no other choice than to remove anything that unbalances the frame or that has suffered from the cold.
The plants should be able to start again without worry in the spring. After severe pruning, expect a more moderate and later flowering than usual, but this is only temporary. Indeed, the following year, the dipladenias will flower much more abundantly.
The formation size of a Dipladenia
Carried out in summer, it is the one that allows reduce stems that are too long and that we no longer have the possibility of guiding. The goal is to avoid the clutter effect. So we put a little order in all this so that the Mandevilla retains an orderly appearance. In addition to pruning, or even cutting back the stems which have grown considerably, it is obviously necessary to eliminate all the faded flowers and the few dry leaves during this beauty session.
Mandevilla fall pruning
In all regions where autumn frosts are severe, dipladenias must be wintered in a frost-free room in order to overwinter without risk. The importance of this pruning which precedes wintering is to be determined according to the luminosity from which the plants will benefit throughout the off-season. If they have to be placed in a dark room, at most equipped with a very small skylight, it is necessary to lower both large and small dipladenias accordingly. On the other hand, in the event of wintering in a very bright room, only the large subjects are folded down.
Finally, any Dipladénia that has been attacked by parasites such as scale insects, aphids and sometimes even whiteflies either during the winter or during the summer, must be sanitized. Stems affected by an infestation should be eliminated during pruning carried out just before wintering or at the end of winter. Gloves should be worn when handling dipladenias to protect against the risk of skin irritation because the milky juice of these plants is toxic.